Improving the comfort of the car
In some cases, the electronic system improves not only any properties of the car, for example, its active security, but also increases its comfort. An example of such a device is a modern wiper control system. Given this circumstance, this paragraph considers only those devices, the main purpose of which is to create a comfortable environment for the driver. Information about devices that primarily serve to improve other technical and operational properties vehicle, although they increase comfort, are given in other paragraphs.
The opposite situation is also possible, when electronic devices created as comfort systems, along the way, have improved other properties of the car. So, the systems for maintaining a constant speed made it possible to obtain noticeable fuel savings, etc.
Comfort devices help to create the best psychophysiological state of the driver, thereby increasing driving safety. Therefore, electronic systems that improve the comfort of the vehicle cannot be regarded as a luxury. Let's look at the following examples.
In areas with hot climates in high-class cars, for example, the American company Cadillac, Seville, Eldorado, air conditioners are widely used, which provide full air exchange in the cabin for 15-20 seconds with drying and heating. At an outside air temperature of 54 ° C, the temperature in the car interior is set to 25 ° C for 10 minutes. The cost of air conditioners reaches 10% of the cost of a car.
The Cedric-Gloria car of the Nissan concern is equipped with a modern air conditioning system in the cabin. The system is intended for automatic stabilization of the set value of the air temperature in the passenger compartment as a result of adjusting the temperature and flow rate of the supplied air. The air temperature outside and inside the passenger compartment is used as the initial data.
The system consists of two nodes. The unit, installed at the front of the vehicle, is designed to adjust the position of the air intake diffuser. An assembly located at the rear of the vehicle automatically regulates the supply of cooled air. The passenger in the rear seat-denier can change the speed of the fan located in the rear of the passenger compartment and regulate the degree of air cooling.
Development of electronic systems control of air conditioning was accompanied by the solution of a number of difficult tasks. For example, in the cars of the General Motors concern, at the first stages, the system reacted to electromagnetic interference and often heated the air when it needed to be cooled.
The choice of the best place to install the temperature sensor inside the passenger compartment was also a significant difficulty due to the radiation effect from the walls of the car.
It is no coincidence that the system of the Nissan concern uses two air temperature sensors inside the passenger compartment.
The operation of the air conditioner requires a lot of energy, therefore, at a low crankshaft rotation speed, usually at idle speed, the compressor is turned on (like gearboxes with automatic control) can cause the engine to overheat or stop. There are several known ways to solve this problem. The easiest one is automatic shutdown compressor clutch at low speed crankshaft engine. In more complex systems, an automatic electronic device, allowing to increase the engine torque when the additional load is turned on as a result of adjusting the ignition timing.
Here's another device. Many drivers neglect due to lack of time correct installation seat position. The degree of inconsistency between the characteristics of the seat and the characteristics of the driver's constitution is reflected not only on the well-being of a person, but also on the rate of increase in fatigue, that is, in the final analysis, on traffic safety. Bosch and Keiper Automobiltechnik have developed “a system that allows the driver to quickly and without hassle restore the previously selected best seat position after adjusting the adjustment.
The principle of the system is simple. The seat frame has four electric motors that change the backrest position and seat height, cushion tilt and seat-to-dash distance. The driver, by pressing the appropriate buttons, controls the electric motors and finds the most comfortable position for himself. At the end of the selection, press a specific button. In this case, the digitized data corresponding to the given position of the seat is entered into the memory from four potentiometers connected to the electric motors.
The memory device can record two or three seat positions. Thus, on one car, two (three) drivers can memorize the most comfortable seat positions for themselves, or one driver can fix several positions corresponding to different driving modes.
After changing the seat adjustment, the driver restores the previously selected position by pressing a button. At the same time, relays are activated, supplying power to the electric motors, which change the seat position until it reaches the set parameters stored in the memory device.
The disadvantage of the described system is that information about the positions of the seat is stored only as long as voltage is applied to the memory device from battery car. After disconnecting the battery, it is necessary to re-organize the entry into the memory of the data on the desired positions.
A similar system installed on a Lagonda car is devoid of this drawback. The system has six buttons to control the position of the seat: height, distance to the dashboard and backrest tilt. Two buttons are used to memorize the two best positions, which remain in memory after disconnecting the power supply.
In some cases, for example, when driving on a road with low traffic intensity, the driver tries to keep the driving speed constant. This task can be successfully solved with the help of a constant velocity device (HIPS) of movement.
Modern devices of this type include a device developed by Bosch and installed on Audi-5000 cars of Volkswagen concern. The driver, pressing a button on the turn signal lever, instructs the vehicle to move with a constant acceleration of 1 m / s2. When the desired speed is reached, he releases the button and the electronic device itself maintains a constant speed value. If the car is moving at the required speed and further acceleration is not needed, you can press and immediately release the button.
The HIPS allows depressing the throttle control pedal to increase the speed at the right time, for example, when overtaking. After the end of the maneuver, an automatic return to the previously set mode is provided. To disable the HIPS, simply press the brake pedal. The speed stabilization error does not exceed 2 km / h for the entire range of engine power output.
To reduce the likelihood of unintentional activation, the device reacts to pressing a button only at a speed greater than 30 km / h. The HIPS has overload protection. It turns off automatically when it exceeds a certain temperature.
In the described device, the value of the desired speed is fixed in the memory of the computing unit after the button is released. If there is a difference between the setpoint and the actual speed value, the electric motor is switched on, changing the position throttle... In cars with powerful engines, vacuum devices are usually used to rotate the throttle valve instead of an electric drive.
TO Category: - Automotive electronics
The study of the working conditions of drivers indicates a significant value of the parameters of the internal environment in the car. These parameters are only more or less likely to comply with the established standards, which makes it possible to extend the concept of reliability to a system that provides living conditions for people in a car. Operational observations are indirect evidence of its insufficient reliability in a number of cases. According to the results of a survey of a large number of professional drivers on the influence of internal environmental factors, the temperature regime in the cab (hot in summer, cold in winter) was negatively assessed - 49% of drivers; the presence of toxic substances (air pollution with exhaust gases) - 60%; the influence of vibrations - 45%, noise -
56% of the surveyed drivers.
1.13.1. Climatic comfort
Abnormal climatic conditions in the car cab have a detrimental effect on the health of the driver and are one of the reasons contributing to the occurrence of an accident. Under the influence of high or low temperatures in the cab of the car, the driver's attention is dulled, visual acuity decreases, reaction time increases, fatigue quickly sets in, errors and miscalculations appear that can lead to an accident.
One of the requirements of occupational safety and health is the exclusion of the possibility of penetration into the driver's cab of workers
gases that contain a number of toxic components, including carbon monoxide. Depending on the proportion of carbon monoxide in the air and the duration
the impact of the driver's work in such an atmosphere is different.
The most characteristic signs with minor poisoning are drowsiness, a feeling of fatigue, intellectual passivity, impaired
spatial coordination of movements, errors in determining the distance and an increase in the latency period in sensorimotor reactions. Studies have shown that only a small amount of
amount of carbon monoxide to make some people feel stupefied, stupefied, headache, sleepy, and disorientated. such deviations that can lead to a run off the road, an unexpected turn of the steering wheel, falling asleep.
Carbon monoxide is sucked into the passenger compartment along with exhaust gases in case of technical malfunctions of the car. Free from any odor and color, carbon monoxide remains completely
imperceptible. In this case, a working person is poisoned three times faster than a person who is at rest.
It should be borne in mind that carbon monoxide also enters the driver's workplace together with the exhaust gases emitted by engines of other vehicles. This is especially dangerous for drivers of passenger cars - taxis, city buses and trucks systematically working in conditions of heavy and heavy traffic of vehicles in cities, the highways of which are filled with exhaust gases.
Studies of the air in the cabins of drivers and in passenger cabins of buses have shown that in some cases the content of carbon monoxide reaches 125 mg / m3, which is several times higher than the maximum permissible concentration for the driver's working area. Therefore, driving a car for more than 8 hours in a city is extremely dangerous due to the possibility of poisoning the driver with carbon monoxide.
Conditions in which a person does not experience overheating or hypothermia, sudden air movement and other unpleasant sensations can be considered thermally comfortable. Comfortable conditions in winter period slightly differ from the same conditions in the summer, which is associated with the use of different clothes by a person. The main factors that determine the thermal state of a person are temperature, humidity and air speed, temperature and properties of the surfaces surrounding a person. With various combinations of these factors, it is possible to create equally comfortable conditions in the summer and winter periods of operation. In view of the variety of features of heat exchange between the human body and the external environment, the choice of a single criterion that characterizes comfortable conditions and is a function of environmental parameters is a difficult task. Therefore, comfortable conditions are usually expressed by a set of indicators that limit individual parameters: temperature, humidity, air speed, maximum air temperature difference in the body and outside, temperature of surrounding surfaces (floor, walls, ceiling), radiation level, air supply to a confined space (body , cabin) per person per unit of time or air exchange rate.
Comfortable values of air temperature and humidity, recommended by various researchers, are somewhat different. So, the Institute of Hygiene
doing light work, the air temperature in winter
20 ... 22 ° С, in summer +23 ... 25 ° С at a relative humidity of 40 ... 60%.
The permissible air temperature is + 28 ° С at the same humidity and its insignificant speed (about 0.1 m / s).
According to the results of French researchers, for light winter work, the recommended air temperature is +18 ... 20 ° C with a humidity of 50 ... 85%, and
for summer +24 ... 28 ° С with air humidity 35 ... 65%.
According to other foreign data, car drivers must work at lower temperatures (+15 ... 17 ° C in the winter period of operation and
18 ... 20 ° С in summer) at a relative humidity of 30 ... 60% and
the speed of its movement is 0.1 m / s. In addition, the temperature difference between the outside air and inside the body during the summer period should not exceed 10 ° C. The temperature difference inside the limited volume of the body in order to avoid colds in humans should not exceed 2 ... 3 ° C.
Depending on the working conditions, to ensure comfortable conditions, the temperature in winter can be taken equal to + 21 ° С with light
work, + 18.5 ° С at moderate, + 16 ° С at heavy.
Currently, in Russia, microclimatic conditions on cars are regulated.
So, for cars, the air temperature in the cab (body) in the summer period should not be higher than +28 C, in winter (at an outside temperature of –20 ° C) - not less than + 14 ° C. In summer, when the car is moving at a speed of 30
km / h the difference between the internal and external air temperature at the driver's head level should not be more than 3 ° С at an external temperature of + 28 ° С and more than 5 ° С at an external temperature of + 40 ° С. In winter time in the zone
the location of the driver's legs, waist and head should be at a temperature not lower than + 15 ° С at an external temperature of –25 ° С and not lower than + 10 ° С at an external temperature of –40 ° С.
Air humidity in the cabin should be 30 ... 70%. The supply of fresh air to the cab must be at least 30 m3 / h per person, the air speed in the cab and the car interior must be 0.5 ... 1.5 m / s. The maximum concentration of dust in the cab (passenger compartment) should not exceed 5 mg / m3.
Ventilation system devices must create an overpressure of at least 10 Pa in a closed cabin.
The maximum concentration of dust in the cab (passenger compartment) should not exceed 5 mg / m3.
The maximum permissible concentration of harmful substances in the air of the working areas of the passenger compartment and cabin of the car is regulated by GOST R 51206 - 98 for cars, in particular: carbon monoxide (CO) - 20 mg / m3; nitrogen oxides in terms of NO2 - 5 mg / m3; total hydrocarbons (Сn Нm) - 300 mg / m3; acrolein (С2Н3СНО) - 0.2 mg / m3.
The concentration of gasoline vapors in the passenger compartment and cabin of the car should not exceed 100 mg / m3.
The temperature regime in the cab (body) can be approximately
calculated according to the heat balance equation, according to which the air temperature in the cab (body) remains constant:
Heat supply to the cabin from various sources. V
in most cases, the thermal balance of the cabin (cabin) is determined by a number of factors, the main of which are: the number of people in the cabin (cabin) and
quantity of heat
QCH coming from them; quantity of heat,
coming through transparent barriers
(mainly from
solar radiation) and opaque fences
(quantity of heat,
coming from the engine
QДВ, transmissions
QTP, hydraulic equipment
electrical equipment with a fan.
Thus,
QEO) and together with external air
QVN supplied
ΣQi QCH QCH QP.O QNP.O QDV QTP QGO QEO QVN 0
It should be noted that the terms of the heat balance included in the equation should be taken into account algebraically, i.e. with a positive sign when heat is released into the cabin and with a negative sign when it is removed from the cabin. Obviously, the heat balance condition is satisfied if the amount of heat entering the cabin is equal to the amount of heat removed from it.
Temperature conditions and air mobility in car cabins are provided by heating, ventilation and air conditioning systems.
Currently, there are various ventilation and heating systems for cabins and car interiors, differing in the layout and design of individual units. The most economical and widely used on
modern cars are heating systems that use the heat of liquid cooling the engine. The combination of heating systems and general ventilation of the cab allows to increase the efficiency of the entire complex of devices for providing a microclimate in the cab throughout the year.
Heating and ventilation systems differ mainly in the location of the air intake on the outer surface of the car, the type of fan used and its location relative to the radiator
heater (at the inlet or outlet of the radiator), the type of radiator used (tubular-plate, tubular-tape, with an intensified surface, matrix, etc.), the control method
the operation of the heater, the presence or absence of a bypass air duct,
recirculation channel, etc.
Air intake from outside the cab into the heater is carried out in the place of minimum dustiness of the air and maximum dynamic pressure,
arising from the movement of the car. In trucks, the air intake is located on the roof of the cab. Water-reflecting partitions, blinds and covers are installed in the air intake,
driven from inside the cab.
To provide air supply to the cabin and overcome the aerodynamic resistance of the radiator and air ducts, an axial fan is used,
radial, diametrical, diagonal or other type. Currently, the most widespread is a double-cantilever radial fan, since it has relatively small dimensions with a large
productivity.
DC motors are used to drive the fan. The rotational speed of the electric motor and, accordingly, the fan impeller is controlled by a two- or three-stage variable resistor included in the power supply circuit of the electric motor.
The heat output of the heater and its
aerodynamic resistance. To increase the efficiency of heat transfer from the radiator, the shape of its channels through which the air moves is complicated, and various turbulators are used.
The air diffuser plays a decisive role in the efficient and uniform distribution of temperatures and air velocities in the cab. The air distributor nozzles are of various shapes: rectangular,
round, oval, etc. They are placed in front of the windshield glass, near the door glass, in the center of the instrument panel, at the driver's feet and in other places determined by the requirements for the distribution of intake air
flows in the cockpit.
Various dampers, rotary blinds,
control plates, etc. The drive to the dampers and rotary louvers is most often located directly in the air distributor housing.
Air ducts to the air distributor are made of sheet steel, rubber hoses, corrugated plastic pipes, etc. V
some cars use cab parts as air ducts, the cavity of the instrument panel. However, such a design of air ducts is irrational, since tightness is not ensured and air consumption increases. Vehicle traffic safety is largely
depends on reliable and effective protection of the windshield from fogging and freezing, which is achieved by uniformly blowing warm air and heating it to a temperature above the dew point.
Such glass protection is structurally simple, does not impair its optical properties, but requires an increase in the performance of the ventilation system and a high heat capacity of the glass. The effectiveness of the jet glass protection against
fogging is determined by the temperature and air velocity at the outlet of the nozzle located in front of the glass edge. The higher the air velocity at the outlet of the nozzle, the less the temperature in the glass zone differs from
temperature at the outlet of the nozzle.
The layout of the ventilation and heating system depends on the design of the vehicle, cab, individual units and their location.
Currently, air conditioners are widespread - devices for
artificial cooling of air entering the cab (body). According to the principle of operation, air conditioners are divided into compression, air-cooled, thermoelectric and evaporative. Automatic control of the heater operating mode in some vehicles is carried out by changing the flow rate of fluid or air through the heater radiator. With automatic regulation by changing
air flow parallel to the radiator, a bypass air channel is made, in which a controlled damper is installed.
As already noted, an important place in the ventilation system of the cab (body)
the car is occupied by cleaning the ventilation air from dust.
The most common way is to clean the ventilation air using filters made of cardboard, synthetic fiber materials,
modified polyurethane foam, etc. However, for the effective use of such filters, which have a low dust holding capacity,
dust concentration at the inlet to the filter. For preliminary air purification, dust separators of inertial type are installed at the filter inlet with continuous removal of captured dust.
The basic principles of dedusting ventilation air are based on the use of one or more mechanisms for the deposition of dust particles from the air: the inertial effect of separation and the effects of entanglement and
deposition.
Inertial settling is carried out with a curvilinear movement of dusty air under the action of centrifugal and Coriolis forces. On
the deposition surface is discarded such particles in which the mass or velocity is significant and they cannot follow with the air along the flow line around the obstacle. Inertial settling is manifested and
when the obstacles are filter filling elements made of fibrous materials, the ends of flat sheets of inertial louvered grilles, etc.
When dusty air moves through a porous partition, particles
suspended in the air, stay on it, and the air completely passes through it. Studies of the filtration process are aimed at establishing the dependence of the dust collection efficiency and aerodynamic resistance on the structural characteristics of porous partitions, dust properties and air flow regime.
The air purification process in fiber filters takes place in two stages.
In the first stage, particles are deposited in a clean filter without structural changes in the porous partition. In this case, changes in the thickness and composition of the dust layer are insignificant and can be neglected. At the second stage, there are continuous structural changes in the dust layer and further deposition of particles in significant quantities. At the same time, the efficiency of dust collection of the filter and its aerodynamic resistance change, which complicates the calculation of the filtration process. The second stage is complex and poorly studied; in operating conditions, it is it that determines the efficiency of the filter, since the first stage is very short-lived. Of the whole variety of filter materials used in the filters of the ventilation air dedusting system of cabins, three groups can be distinguished: woven from natural, synthetic and mineral fibers; non-woven - felt, paper, cardboard, needle-punched materials, etc.; cellular - polyurethane foam, spongy rubber, etc.
For the manufacture of filters, materials of organic origin and artificial are used. Organic materials include cotton, wool. They have low temperature resistance, high moisture capacity. A common disadvantage of all filtering materials of organic origin is their susceptibility to putrefactive processes and the negative effect of moisture. Synthetic and mineral materials include: nitron, which is highly resistant to temperatures, acids and alkalis; chlorane, which has low thermal stability, but high chemical resistance; nylon, characterized by high abrasion resistance; oxalon having high heat resistance; fiberglass and asbestos, which are characterized by high heat resistance, etc. The filter material made of lavsan has high indicators of dust-collecting, strength and regeneration parameters.
Non-woven needle-punched lavsan are widely used in filters with impulse air blowing during filter regeneration.
filtering materials. These materials are obtained by compaction of fibers followed by needling or needling.
The disadvantage of such filter materials is the passage of more
fine dust particles through the holes formed by the needles.
A significant drawback of filters made of any filter material is the need to replace them or Maintenance with the aim of
regeneration (recovery) of the filter material. Partial regeneration of the filter can be carried out directly in the ventilation system by backflushing the filter material with purified air from the car cab or by local jet blowing with air.
from a compressor with preliminary cleaning of compressed air from water and oil vapors.
Filter construction made of woven or non-woven filter materials
for cab ventilation systems, it must have a maximum filtration surface with minimum dimensions and aerodynamic resistance. The installation of the filter in the cabin and its change should be convenient and ensure reliable tightness around the filter perimeter.
1.13.2. Vibration comfort
From the point of view of reaction to mechanical excitations, a person is a kind of mechanical system. At the same time, various internal organs and individual parts of the human body can be considered as masses interconnected by elastic bonds with the inclusion of parallel resistances.
The relative movements of parts of the human body lead to stresses in the ligaments between these parts and mutual collision and pressure.
Such a viscoelastic mechanical system has natural frequencies and rather pronounced resonance properties. Resonant
the frequencies of individual parts of the human body are as follows: head - 12 ... 27 Hz,
throat - 6 ... 27 Hz, chest - 2 ... 12 Hz, legs and arms - 2 ... 8 Hz, lumbar spine - 4 ... 14 Hz, abdomen - 4 ... 12 Hz. Degree harmful effects vibrations on the human body depends on the frequency, duration and direction of vibration, individual characteristics of a person.
Long-term human vibrations with a frequency of 3 ... 5 Hz adversely affect the vestibular apparatus, cardiovascular system and cause motion sickness syndrome. Vibrations with a frequency of 1.5 ... 11 Hz cause disturbances due to resonant vibrations of the head, stomach, intestines and ultimately the whole body. With vibrations with a frequency of 11 ... 45 Hz, vision deteriorates, nausea, vomiting occurs, and the normal activity of other organs is disrupted. Oscillations with a frequency of more than 45 Hz cause damage to the vessels of the brain, a disorder of blood circulation and higher nervous activity occurs, followed by the development of vibration disease. Since vibration with constant exposure has an adverse effect on the human body, it is normalized.
The general approach to vibration regulation is to limit the vibration acceleration or vibration velocity measured at the driver's workplace in
depending on the direction of the vibration, its frequency and duration.
Note that the smooth running of the machine is characterized by general vibration,
transmitted through the support surfaces to the body of a seated person. Local vibration is transmitted through the hands of a person from the controls of the machine, and its effect is less significant.
Dependence of the mean square value of the vertical
the vibration acceleration az of a seated person from the vibration frequency with his constant vibration load is shown in Fig. 1.13.1 (curves of "equal concentration"), from which it can be seen that in the frequency range f = 2 ... 8 Hz, the sensitivity of the human body to vibration increases.
The reason for this is precisely the resonant vibrations of various parts of the human body and its internal organs. Most curves
"Equal thickening" are obtained when the human body is exposed to harmonic vibration. In case of random vibration, the curves of "equal concentration" in different frequency ranges have general character, but
quantitatively differ from harmonic vibration.
Vibration hygienic assessment is carried out using one of three methods:
frequency (spectral) analysis; integral estimate of frequency and
"Dose of vibration".
In a separate-frequency analysis, the normalized parameters are the root-mean-square values of vibration velocity V and their logarithmic levels Lv or vibration acceleration az for local vibration in octave frequency bands, and for general vibration - in octave or one-third octave frequency bands. When normalizing vibration, "equal thickening" curves were first taken into account in the ISO 2631-78 standard. The standard establishes the permissible root-mean-square values of vibration acceleration in one-third octave bands
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frequencies in the range of geometric mean frequencies 1 ... 80 Hz with different duration of vibration. The ISO 2631-78 standard provides for the assessment of both harmonic and random vibration. In this case, the direction of the general vibration is usually estimated along the axes of the orthogonal coordinate system (x - longitudinal, y - transverse, z - vertical).
Rice. 1.13.1. "Equal thickening" curves with harmonic vibration:
1 - the threshold of sensations; 2 - the beginning of unpleasant sensations
A similar approach to vibration regulation is used in GOST
12.1.012-90, the provisions of which are the basis for determining the criterion and indicators of smooth running of cars.
As a criterion for smooth running, the concept of "safety" is introduced, not
causing health problems for the driver.
Ride indicators are usually assigned according to the output value, which is the vertical vibration acceleration az or the vertical vibration velocity Vz, determined on the driver's seat. It should be noted here that when assessing the vibration load on a person, vibration acceleration is the preferred output value. For sanitary standardization and control, the vibration intensity is estimated by the mean square
value az
vertical vibration acceleration, as well as its logarithmic
Threshold rms vertical
vibration acceleration.
Mean square value az
called "controlled
parameter ", and the smoothness of the machine is determined with constant vibration in the frequency range of 0.7 ... 22.4 Hz.
With the integral assessment, a frequency-corrected value of the controlled parameter is obtained, with the help of which the ambiguity of a person's perception of vibration with a different spectrum is taken into account
frequencies. Frequency-corrected value of monitored parameter az
and its logarithmic level
are determined from the expressions:
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~ ∑ (k zi a zi);
10 lg ∑100,1 (Lazi Lkzj),
- root-mean-square value of the controlled parameter
and its logarithmic level in the i-th octave or one-third octave band;
- weighting factor for the mean square value
of the controlled parameter and its logarithmic level in the i-th band
kzi i; n is the number of bands in the normalized frequency range.
The values of the weighting factors are given in Table 1.13.1.
Table 1.13.1
The average value of the frequency of one-third octave and
Third octave frequency band
Octave frequency band
octave bands
According to sanitary standards, with a shift duration of 8 hours and general vibration, the standard root-mean-square value of vertical vibration acceleration is 0.56 m / s2, and its logarithmic level is 115 dB.
When determining the vibration load on a person using the vibration spectrum, the standardized indicators are the root-mean-square value of vibration acceleration or its logarithmic level in one-third octave and octave frequency bands.
The permissible values of the spectral indicators of the vibration load on a person are given in table. 1.13.2.
Table 1.13.2
Sanitary norms of spectral indicators of vibration load for vertical vibration acceleration
geometric
Normative mean
square value
Regulatory
logarithmic
one-third octave frequency
vibration acceleration
vibration acceleration
and octave
Third octave
frequency band
Octave
frequency band
Third octave
frequency band n
In the case of using the integral and separate-frequency methods for assessing the vibration load on a person, you can come to different results. As a priority, it is recommended to use the method of separate-frequency (spectral) assessment of vibration load.
Currently, the standard indicators of the smoothness of the machine, such as vibration acceleration and
vibration velocities in the vertical and horizontal planes, set differentially for different vibration frequencies.
The latter are grouped into seven octave bands with an average geometric frequency from 1 to 63 Hz (Table 1.13.3.).
Table 1.13.3
Standard indicators for the smooth running of transport vehicles
Parameter
Vibration speed,
Average geometric vibration frequency, Hz
1 2 4 8 16 31,5 6
vertical horizontal Vibration acceleration, m / s2: vertical horizontal
On a number of special wheeled and tracked vehicles operating in difficult road conditions, where the amplitudes of the micro-profile are significant, it is difficult to ensure the values of the smoothness indicators, regulated for transport equipment... Therefore, for such machines, standard indicators of smoothness are set at a lower level (tab.
Table 1.13.4
Ride standard values for machines operating in severe road conditions
Workplace acceleration
driver - (operator)
Vertical:
mean square maximum from episodic
shocks
maximum from rotary jolts
Horizontal RMS
Transport traction
Ride standards for trucks, buses, cars, trailers and semi-trailers are determined for three types of sections of the NAMI auto-range:
I - a cement dynamometric road with a root mean square value of the heights of irregularities of 0.006 m;
II - pothole-free cobblestone road with RMS
roughness values of 0.011 m;
III - cobbled road with potholes with an rms roughness of 0.029 m.
The standards of smooth running of cars, established by OST 37.001.291-84,
are given in table. 1.13.5, 1.13.6, 1.13.7.
To improve the indicators of the smooth running of cars, the following measures are used:
The choice of the layout scheme of the car, which ensures the independence of vibrations on the front and rear suspension sprung weight of the machine;
Selection of the optimal characteristics of suspension elasticity;
Ensuring the optimal ratio of the stiffness of the front and rear suspensions of the car;
Reducing the mass of unsprung parts;
Suspension of the cab and seat of the driver of a truck and a road train.
Table 1.13.5
Limit technical standards smooth running of trucks
Corrected values of vibration accelerations on seats, m / s2, not more
horizontal
RMS vertical
vibration accelerations in
vertik roads
longitudinal
characteristic points of the sprung part, m / s2, not more
Table 1.13.6
Limiting technical standards for the smooth running of passenger cars
Corrected values of vibration accelerations on the driver's and
Road type
passengers, m / s2, no more
vertical horizontal
Table 1.13.7
Limiting technical standards of smooth running of buses
Corrected values of vibration accelerations on bus seats, m / s2, no more
other urban types
driver passengers driver and passengers
1.13.3. Acoustic comfort
Various noises are generated in the vehicle cab, which negatively affect the driver's performance. First of all, the auditory function suffers, but noise phenomena, possessing cumulative properties (i.e. properties to accumulate in the body), depress the nervous system, while psychophysiological functions change, the speed and accuracy of movements are significantly reduced. Noise causes negative emotions, under its influence the driver gets distracted, apathy, memory impairment. Human exposure to noise can be subdivided into the following groups, depending on the intensity and spectrum of noise:
Very strong noise with levels of 120 ... 140 dB and above - regardless of the spectrum, it can cause mechanical damage to the hearing organs and cause severe damage to the body;
Strong noise with levels of 100 ... 120 dB at low frequencies, above 90 dB at medium frequencies and above 75 ... 85 dB at high frequencies - causes irreversible changes in the hearing organs, and with prolonged exposure it can be
the cause of a number of diseases and, first of all, of the nervous system;
Noise more low levels 60 ... 75 dB at medium and high frequencies has a harmful effect on the nervous system of a person engaged in work that requires focused attention, to which work belongs
car driver.
Sanitary standards divide noise into three classes and establish an acceptable level for them:
Class 1 - low-frequency noise (the largest components in the spectrum are located below the frequency of 350 Hz, above which the levels decrease) with an allowable level of 90 ... 100 dB;
Class 2 - mid-frequency noise (the highest levels in the spectrum
located below 800 Hz, above which the levels decrease) with an allowable level of 85 ... 90 dB;
Class 3 - high-frequency noise (the highest levels in the spectrum are located above 800Hz) with an acceptable level of 75 ... 85 dB.
Thus, noise is called low-frequency when the vibration frequency is not
more than 400 Hz, mid-frequency - 400 ... 1000 Hz, high-frequency - more
1000 Hz. In this case, according to the frequency of the spectrum, the noise is classified into broadband, which includes almost all frequencies of sound pressure (the level is measured in dBA), and narrowband (the level is measured in dB).
Although the frequency of acoustic sound vibrations is in the range of 20 ... 20,000
Hz, its normalization in dB is carried out in octave bands with a frequency of 63 ...
8000 Hz constant noise. The characteristic of non-constant and broadband noise is equivalent in energy and perception
human ear sound level in dBA.
Permissible internal noise levels for vehicles on
GOST R 51616 - 2000 are given in table. 1.13.8.
It should be noted that the permissible levels of internal noise in the cab or passenger compartment are established regardless of whether there is a single source.
noise or several of them. Obviously, if the sound power emitted by one source meets the maximum permissible sound pressure level at the workplace, then when installing several such sources
the specified maximum permissible level will be exceeded due to the addition of their effects. As a result, the overall noise level is determined by the energy summation law.
Table 1.13.8
Permissible internal noise levels of motor vehicles
Permissible
Motor vehicle
Cars and buses for the transport of passengers
sound level, dB A
M 1, except for wagon models or
half-hood body layout
M 1 - models with wagon or 80
semi-hood body layout.
M 3, except for models with
the location of the engine in front of or near the place
driver: 78 at the driver's workplace 80 in the passenger compartment of class II buses 82
in the passenger compartment of class I buses
Models with 80 layout
engine in front of or near the driver's seat:
at the workplace of the driver and in the passenger 80
premises
Trucks for the transport of goods
N1 full weight up to 2 t 80
N1 with gross weight from 2 to 3.5 t 82
N3, except for models
destined for international and 80
intercity transportation
Models for international and 80
intercity transportation
Trailers for the carriage of passengers 80
Total noise level, dBA, from several identical sources
LΣ L1 10 lg⋅ n,
L1 - noise level of one source, dBA;
n is the number of noise sources.
With the simultaneous action of two sources with different sound pressure levels, the total noise level
LΣ La ∆L,
- the largest of the two summed noise levels;
∆L - additive depending on the difference in noise levels of two sources
∆L values
depending on the difference in noise levels of the two sources
> Lb) are shown below:
|
La - Lb, dBA ... ..0 1 |
|||
|
∆L, dBA ... ... 3 2.5 |
It is obvious that if the noise level of one source is higher than the level of the other by
8 ... 10 dBA, then the noise of a more intense source will prevail, since
in this case, the addition ∆L
very small.
The total noise level of sources of different intensity is determined by the expression
−0,1∆L1, n
Σ 1 10 lg 1 10
... 10 ,
L1 - the highest noise level of one of the sources;
∆L1, 2 - L1 - L2;
∆L1,3 L1 - L3; ∆L1, n L1 - Ln ⋅ L2, L3, ...., Ln
Noise levels
respectively 2nd, 3rd, ..., nth sources). Calculation of the noise level, dB A,
with a change in the distance to the source is performed according to the formula
Lr Lu - 201gr - 8,
- source noise level; r is the distance from the noise source to
the object of his perception, m.
The general noise of a moving car is made up of noise generated by the engine, aggregates, car body and its components, noise of auxiliary equipment and tire rolling, as well as noise from the air flow.
Noise in a specific source is generated by certain physical phenomena, among which the most characteristic in a car are:
impact interaction of bodies; friction of surfaces; forced vibrations of rigid bodies; vibration of parts and assemblies; pressure pulsation in pneumatic and hydraulic systems.
In general, the sources of vehicle noise can be divided into the following:
Mechanical - engine internal combustion, body parts,
transmission, suspension, panels, tires, tracks, exhaust system;
Hydromechanical - torque converters, fluid couplings, hydraulic pumps,
hydraulic motors;
Electromagnetic - generators, electric motors;
Aerodynamic - intake and exhaust system of an internal combustion engine, fans.
Noise has a complex structure and consists of the noise of individual sources. The most intense sources of noise are:
structural engine noise (mechanical and combustion noise), intake and system noise, exhaust and exhaust system noise, cooling fan noise, transmission noise, tire rolling noise (tire noise), body noise. Long-term research has established that the main sources of noise generation in a car include the internal combustion engine, transmission elements, tires, aerodynamic noise. A secondary source of noise is the body panels. Additional sources include noises from engine attachments, some transmission elements, electric motors, heaters, windshield blowing, doors slamming, etc.
The listed sources generate mechanical and acoustic vibrations, different in frequency and intensity. The nature of the frequency spectrum
disturbances are very difficult to analyze due to the overlap and interconnection in the frequencies of working processes and disturbances from transmission elements, chassis, aerodynamic processes, etc.,
and also due to the fact that many sources are simultaneously causative agents of mechanical and acoustic vibrations. The vibration spectra of the main transmission units and noise show up mainly
harmonic components from main sources of excitation
(engine and transmission).
The dynamic interaction of parts of vehicle units generates vibrational energy, which, spreading from vibration sources,
creates a sound field of a car, a tractor, i.e. car noise.
Accordingly, the following paths can be identified to reduce the noise intensity:
Reducing the vibration activity of the units, i.e. reducing the level of vibrational energy generated in the source;
Taking measures to reduce the intensity of vibrations on their way
distribution;
Impact on the process of radiation and transmission of vibrations to attached parts, i.e. decrease in their vibroacoustic activity.
Reducing the vibration activity of the source is achieved by improving the kinematic properties of vehicle systems and choosing the parameters of mechanical systems so that their resonant frequencies are
are maximally removed from the frequency range containing the operating frequencies of the units, as well as by minimizing the vibration levels at the reference points and minimizing the amplitudes of forced vibrations. Reducing noise can be achieved by creating a low-noise process
combustion, improving the vibroacoustic characteristics of body parts, units, introducing damping into their design, improving the design and manufacturing quality of movable
parts, increasing the acoustic efficiency of intake and exhaust silencers, etc.
Combating noise and vibration as it propagates in the process
radiation and transmission of vibrational energy to attached parts and
units can be made by "detuning" the system of bearing elements from resonance states by vibration isolation, vibration damping and vibration damping.
Vibration isolation - the choice of such parameters of mechanical systems that ensure the localization of vibrations in a certain area of the car without
its further distribution.
Vibration damping - the use of systems that actively dissipate the vibration energy of vibrating surfaces, as well as the use of materials with a large decrement
attenuation.
Vibration damping - use in units tuned to a certain frequency and mode of vibration, systems operating in antiphase.
Suppression of noise at its source is an active method of noise suppression and the most radical means of dealing with noise. However, in many cases, this method, for one reason or another, does not
it is possible to apply. Then you have to resort to passive methods of protection against noise - vibration damping of surfaces, sound absorption, sound insulation.
Sound insulation refers to the reduction in sound (noise) to the receiver due to reflection from obstacles in the transmission path. The sound-insulating effect always occurs when sound passes through
waves across the interface between two different media. The greater the energy of the reflected waves, the less the energy of the transmitted waves, and, therefore, the greater the sound insulating ability of the interface between the media. The more sound energy is absorbed by the obstacle, the higher its sound-absorbing
ability.
Noise caused by medium and high frequency vibrations is transmitted to the passenger compartment mainly through the air. To reduce this transmission, a special
attention should be paid to sealing the cabin, identifying and eliminating acoustic holes (acoustic holes). Acoustic holes can be through and non-through slots, technological holes, areas with
low sound insulation, significantly impairing the overall sound insulation of the structure.
From the point of view of the features of the transmission of sound energy, they are distinguished
large and small acoustic holes. A large acoustic hole is characterized by a large, in comparison with unity, ratio of the linear dimensions of the hole to the length of the sound wave incident on the hole. In practice, we can assume that sound waves pass through a large acoustic hole according to the laws of geometric acoustics and that the sound energy passed through the hole is proportional to its area. Each hole category has one or more effective methods their elimination.
To determine effective ways to reduce noise, it is necessary to know the most intense noise sources, to separate them, and also
determine the need for and the magnitude of the reduction in the levels of each of them.
Having the results of the separation of sources and their levels, it is possible to determine the sequence of fine-tuning the car in terms of noise.
Control questions
1.What is the purpose of regulating the safety of the construction of vehicles?
2. What are the main properties that determine the safety of the structure of vehicles
3. By what criteria is the impact of active vehicle safety on safety determined? road traffic?
4. What is the relationship between vehicle weight and risk
receiving bodily harm in an accident for his passengers?
5. What determines the width of the dynamic corridor during curvilinear movement?
6. What size classes are cars sold in Europe?
with GOST R 52051-2003?
8. What forces act on the car accelerating uphill?
9. What changes in the technical condition of the car affect its traction dynamics and how?
10. What is the dynamic factor of a car?
11. What is called lateral stability car?
12. What is called the longitudinal stability of a car?
13. What is vehicle directional stability?
14. What are the main technical requirements (test methods)
impose on the braking properties of vehicles?
15. What standards regulate the stability and controllability of vehicles as active safety properties?
16. What types of resistance tests do you know?
17. What indicators are assessed in the "stabilization" test?
18. What types of car steering are there?
19. For what technical reasons is the loss of controllability of the car possible?
20. What is the stopping distance of a car?
21. How the Type 0 test is carried out braking systems Vehicle?
22. What indicators determine the requirements for tires and wheels?
23. Indicate the main characteristics of the coupling devices.
24. What devices are used for information support of vehicles?
25. What technical requirements present for lighting and light signaling devices?
If the car is not comfortable, then after traveling, especially for a long distance or in case of idleness in traffic jams, it will cause you fatigue and irritation. Unfortunately, Russian roads leave much to be desired and not all car brands can boast of comfort and convenience.
But we must admit that most modern cars have become better in terms of reliability, quality and comfort. However, there are models that have a huge advantage over other brands in terms of comfort. We offer you our rating of the most comfortable cars. selected for comfort while driving, noise isolation, comfort of the driver's seat and front passenger seat... We have deliberately excluded compact small cars from our list, sports cars and convertibles, which by definition cannot be ideally comfortable due to their size or design features.
Also after reading the best cars for comfort, you can also find out if these models, as well as what they have, by clicking on the photo or the name of the model.
The A6 is very convenient and comfortable. A ride in this car will please even the most experienced driver.
This year's new Impala is modern big sedan. Spacious salon, comfortable, quiet and pleasant to operate. Noteworthy are the large and spacious front seats. They are pleasant to the touch and perfectly support the lower back and relieve stress on the back, which allows you to comfortably travel long distances.
One of best sedans on the market. Space and comfortthe main merit of computer engineersResearch Institute Chrysler. Top-end equipment is the best. The control of all functions of the car is very convenient. Various amenities, luxury items and quietness during the trip will not let you get tired behind the wheel. Especially ideal for a car on the highway where you will not hear loud work motor and tire sound.See also:
The highest comfort is available in a top-of-the-range vehicle. The cabin is quiet. The noise only comes from
ventilation climate control. Also, some noise will bother you for a few minutes after starting the engine in cold weather. After warming up, you will not hear the sound of the motor. The front seats are well-shaped and very comfortable thanks to the support of the lower back. It is worth noting that it is the leather seats that hold the back better than the fabric chairs. Plus, the fabric-trimmed seats are somewhat stiffer than the leather ones, which can lead to fatigue on long trips in traffic.See also:
Complete silence in the cabin. Even at high speed, no wind noise is heard. The interior of the Lexus ES is thought out to the smallest detail.
Maximum comfort. Expensive interior trim pleasantly surprises with its textures. ES models have very quiet engines and expensive soundproofing. The seats are distinguished by their comfort due to their width and balanced softness.Reliability rating
Lexus LS The flagship sedan provides both the driver and passengers with a comfortable and calm journey at any distance. The LS on the road won't be a hassle on any road. Soundproofing at a height. The absorption of extraneous noise is perfect. The smooth running of the car and excellent handling are the main advantages of this model. All seats are very comfortable and luxurious.
A fishing rod or long key is a hijacking method when attackers use a wave system designed for intelligence agencies. Retransmission of the key signal allows you to open the car, even if the owner is at a considerable distance. Ways to combat this type of theft.
During operation, scratches appear on the windows of the car from wipers, scrapers and other fine abrasives. Scratches and abrasions can significantly reduce the driver's visibility while driving, especially in the evening. In order not to change the glass, you can try to polish yourself.
Soundproofing car doors can significantly reduce the level of extraneous sounds in the cabin. The installation procedure for Shumka is not so complicated, so you can do it correctly even with your own hands. What materials are used for noise insulation, what are the positive and negative sides of the installation of noise for doors.
Self-isolation the car is produced by 50% of car owners, while the other half orders this service in specialized workshops. Is it really so difficult to make a Shumka in a car with your own hands, what materials should be used in this case. How much material is needed and what types are better to use.
It is useful to study the rating of the most stolen cars in Russia for all car owners, as well as for those who are just going to purchase a vehicle. The article contains statistics of car thefts since 2014. Fresh data for 2018, by the number of thefts in general and by specific weight.
Double glazing of the car will help to avoid constant fines for the installed tinting. Having spent a certain amount of money once, you can forget about the problem forever. But it is advisable to approach responsibly to the choice of the performer in order to avoid problems with double glazing in the future.
Since the vehicle is a source of increased danger, there is a list of malfunctions, in the event of which the driver is not allowed to use the vehicle at all. There is also a list of malfunctions with which the car can independently continue to move to the point of elimination of the breakdown.
Smell gas in your car? It is necessary to calculate the location of the leak, since you should not joke with gasoline. There can be several reasons for the appearance of the smell. First you need to figure out exactly what moment it appears, and then start the search. Perhaps it starts to smell at the moment the engine is started, and then the smell disappears. We are trying to figure out what is the cause of the smell of gasoline in the car.
Due to the fact that once a law was passed on the permissible level of tinting of car windows, drivers had such a problem as removing the tinting. You can make it in several ways - on your own, or by contacting the workshop. It is not so difficult to remove the tint on your own, it is enough to know how to do it correctly.
Many have heard such an expression as preheater engine. From the name it becomes clear its main function - to facilitate the winter start of the car. There are many different heaters from different manufacturers. By the type of implementation, they can be divided into two: autonomous and electrical. You can learn about each of them from this article.
One of the necessary and important improvements to the car, without a doubt, is such a device as an autonomous interior heater. Thanks to this device, the required temperature can be maintained in the passenger compartment, without the need to start the engine. Such a unit is in the greatest demand among truck drivers, since it allows you to rest on the road under much more comfortable conditions.
A device such as an anti-sleep device allows the driver to avoid an emergency if he is tired and starts to fall asleep while driving. The sharp, shrill signal that the device emits, as soon as the head bends forward, will wake anyone up. By and large, though, it's best not to tempt fate and hope for a device, but just stop and rest.
Tinting, whatever it is, reduces visibility and increases the likelihood of an emergency. Therefore, permissible norms of light transmission have been introduced, and a fine is imposed on drivers who violate these requirements. One of the options to avoid punishment is electric tinting. Read what it is and how it works in this publication.
One of the additional options designed to improve the comfort of the driver and passengers is the heated seats. This option is purely seasonal, but highly demanded. In luxury trim levels, seat heating is present by default, while others can install it on their own, with their own hands.
The rain sensor is optional and is designed to make the driver's life easier and more comfortable. There is no need to turn on and off the wipers yourself, the sensor turns them on independently as soon as windshield, water gets into its zone of action.
The safety of the driver and passengers of the car is a very important issue, and when it comes to children, there can be no compromises at all. For the greatest safety of children, the driver is obliged to use special child seats, which are fastened using the existing belts, or the isofix system, if available. What it is and in which machines it is available, read the article.
Many motorists, entering a corner at a decent speed, felt that a little bit more and the car would roll over. This is due to the impact on the car of centrifugal and other forces. In the fight against the possibility of car rollover, manufacturers equip them with various anti-rollover systems.
Transporting a bicycle by car is often difficult, especially when the car is not very large. What can we say about how to transport several bicycles at once. For this, there are various attachments to the car's towbar, both factory-made (flexfix from opel) and many other solutions.
This article will focus on a special type of glass tinting provided by the manufacturer. skoda car... It is called sunset and can be applied directly at the manufacturer's plant. Whether such an option is needed, is it worth overpaying your hard-earned money for it and what is the use of it - let's try to figure it out.
Heat-insulating glazing, its other name - athermal, protects the car interior from overheating. This is achieved with the help of various additives in the manufacture of glass. Athermal glass is used by car manufacturers skoda and a number of others. Also recently, toning with athermal films is gaining popularity.
Car owners Skoda brands surely familiar with such a concept as the varioflex system. This is a very convenient implementation of the interior space of the passenger compartment, thanks to which the rear row seats can be folded in various variations, and, if necessary, completely removed. The varioflex system makes it possible to convert passenger car almost a full-fledged truck.
Modern car it is already difficult to imagine without such an option as an air conditioner. A great many of them have been invented, and each is good in its own way. In this article, we will talk about the principle of operation of all such systems, and about a semi-automatic air conditioner called climatic.
To maximize the comfort of the driver and passengers, there are a wide variety of different systems. One of these is the seat ventilation system. On expensive cars, in the maximum configuration, this option is found more and more often. But this does not mean that a person with an average income cannot afford seat ventilation. The option of its self-installation is possible.
Cars equipped with keyless entry systems greatly simplify the driver's life. There is no need to arm or disarm the car - the smart key system perfectly copes with all this. It is enough that the electronic key is in your pocket, and then the driver will be identified as the rightful owner of the vehicle.
The power window is the dream of any owner of a domestic vehicle. If now modern VAZ models are equipped with this option already from the factory, then on the classics, for example, the same 2107, you will have to install the window regulator yourself. The article contains information about all possible types of power windows and their design.
What on-board computer in a car, for what purposes it is installed and why it is so popular among car owners. The answer is simple - this device allows you to control many parameters of the car's operation, notify the owner about malfunctions, and generally make life easier for the vehicle owner.
Why do you need a head-up display and to what extent it is able to facilitate driving, as well as to maximize the safety of all road users. Modern electronic means, one of which is a display capable of projecting instrument readings onto the windshield, do an excellent job of increasing safety and comfort.
Surely many of us, at least once, had to fall under such a pouring rain that even the windshield wipers could not cope with the streams of water pouring from the sky. And what could be worse than fine drizzle, which makes the wipers work continuously, but the view still leaves much to be desired. Modern technologies make it possible to process car windows with an anti-rain agent, from which the water simply rolls off the glass.
The system of exchange rate stability, or dynamic stabilization of the car, is necessary in order to prevent an uncontrollable skid at the time of sharp braking, or loss of traction with the road of one of the wheels. Based on the readings of many sensors, the system makes sure that the driver does not get into an emergency due to road conditions or his inexperience.
Noise isolation excites the minds of many car owners, which is not surprising. After all, who does not want to drive a car without hearing the noise of the wheels, enjoy the silence, or say the music in the cabin, which is not muffled by the rustle of gravel under the wheels and the roar of passing cars. Yesterday, the noise insulation procedure was long and expensive, but today, thanks to the appearance of liquid rubber, it is available to everyone.
It is difficult to overestimate the importance of such a system as assisted ascent and descent. It is especially needed, and even necessary for novice drivers who are experiencing problems exactly when they need to move up the hill. Having many names, depending on the manufacturer, the principle of operation of this system remains unchanged.
In the struggle for road safety, mankind is more and more improving the inside of the car in order to achieve comfort and safety. Long travel time invariably affects the condition of the driver, and sometimes driver fatigue leads to fatal consequences.
What is voice control of a car is not difficult to guess from the name of this option. The article will tell you exactly how you can implement the work of such a system, it also contains information about how the voice control system has evolved over time, and how the very first one differs from the latest developments in this area.
What a miracle is an active head restraint and is there any benefit from it for the driver. Let's try to figure it out. Numerous tests have proven that an active head restraint significantly reduces the risk of injury to the driver's cervical vertebrae in a rear impact. Bye this system safety is not often met, but we think that over time everything will change, and the equipment of the car with active head restraints will become the norm.
The car's surround view system is another step towards road safety. This system allows you to monitor the traffic situation around the car in real time. This is achieved due to the video cameras and proximity sensors installed in a circle. Each manufacturer calls their systems differently, but they have the same basic principle of operation.
What expeditionary trunk represent everyone, at least most of the car owners. How important and necessary to have given type the trunk for those who travel by car is a controversial issue. The article describes its main advantages, and also contains information on how you can independently make a trunk from available tools.
There are many road signs, and the driver has only two eyes, so it can be difficult to keep track of everyone. To facilitate control over traffic situation, a device such as a traffic sign recognition system has been invented. She will warn the driver that on this section of the road it is necessary to observe speed mode, or that overtaking is prohibited here. The system is very useful, but as practice shows, it does not always work as it should.
Man has always tried to automate certain processes as much as possible, and driving is no exception. This article will focus on a system such as park assist. The automatic parking system is able to independently park the car, without any human intervention. Regardless of whether the driver is in the car or not, the vehicle will find an empty seat and park the car.
Many sooner or later face a problem when the heating stops working fully rear window... This happens most often due to the breakage of the filaments, which provide this very heating. Let's look at the most simple ways restoration of glass heating, which is within the power of any car enthusiast with straight hands.
We have already found out what an immobilizer is and for what purposes it is needed in a car. In this article, let's discuss when and how a device such as an immobilizer crawler is required. It is clear that this anti-theft protection system can turn against you from the loss of a key, program failure or equipment breakdown. This is where the knowledge of how you can turn off the immobilizer comes in handy.
An immobilizer is an anti-theft device for a car, which works on the principle of blocking certain capabilities of the car, individual components or assemblies, which in turn leads to immobilization of the vehicle. And since hijackers rarely use tow trucks and other loading equipment when hijacking, the chances that a car equipped with an immobilizer will remain with the owner is quite high.
What is parking sensors and is there a need to install it. Nowadays, quite a few varieties of parking sensors have already been invented, with and without cameras, with monitors built into the rear-view mirrors and without them, but the essence of the device remains unchanged - it is designed to make life easier for the driver, especially for a beginner. This is a kind of third eye. How it works and how to install it, read this article.
A central locking in a car is an irreplaceable thing, and it is found, in our time, on the vast majority of cars. What role does central locking, on what principle its work is organized can be read in this article.
Do you buckle up while driving? More and more people in our time, realizing that courage can go sideways, began to take care of themselves first of all and wear a seat belt. And this is very correct. How the procession of seat belts began, what were the first of them, and what the evolution of safety has led to today - about this and another in this article.
