COMFORTABILITY

The comfort of the car determines the time during which the driver is able to drive the car without fatigue. An increase in comfort is facilitated by the use of automatic transmission, speed controllers (cruise control), etc. Currently, vehicles are equipped with adaptive cruise control. It not only automatically maintains the speed at a given level

not, but also, if necessary, reduces it up to a complete stop of the car.

3 Passive vehicle safety

BODY

It provides acceptable loads on the human body from a sharp deceleration in an accident and saves the space of the passenger compartment after the deformation of the body.

In a severe accident, there is a risk that the engine and other components can enter the driver's cab. Therefore, the cabin is surrounded by a special "safety grid", which is an absolute protection in such cases. The same stiffening ribs and bars can be found in the doors of the car (in case of side collisions). This also includes areas of energy repayment.

In a severe accident, there is a sharp and unexpected deceleration to a complete stop of the car. This process causes huge overloads on the bodies of passengers, which can be fatal. It follows from this that it is necessary to find a way to "slow down" the deceleration in order to reduce the load on the human body. One way to solve this problem is to design areas of destruction that dampen the energy of a collision in the front and rear parts of the body. The destruction of the car will be more severe, but the passengers will remain intact (and this is compared to the old "thick-skinned" cars, when the car got off with a "light fright", but the passengers received severe injuries). AAAAAAAAAAAAAAAAAAAAAAAAAAA

The design of the body provides that in the event of a collision, the parts of the body are deformed, as it were, separately. Plus, high-tensioned metal sheets are used in the design. This makes the car more rigid, and on the other hand allows it to be not so heavy.

SEAT BELTS

At first, cars were equipped with two-point belts that “held” riders by the stomach or chest. Less than half a century later, engineers realized that the multi-point design is much better, because in the event of an accident it allows you to distribute the pressure of the belt on the surface of the body more evenly and significantly reduce the risk of injury to the spine and internal organs. In motorsport, for example, four-, five- and even six-point seat belts are used - they keep the person in the seat “tightly”. But on the “citizen”, because of their simplicity and convenience, three-point ones took root.

In order for the belt to work properly for its purpose, it must fit snugly against the body. Previously, belts had to be adjusted, adjusted to fit. With the advent of inertial belts, the need for “manual adjustment” has disappeared - in the normal state, the coil rotates freely, and the belt can wrap around a passenger of any build, it does not hinder actions, and every time a passenger wants to change the position of the body, the strap always fits snugly to the body. But at the moment when “force majeure” comes, the inertial coil will immediately fix the belt. In addition, on modern machines, squibs are used in belts. Small explosive charges detonate, pulling the belt, and he presses the passenger to the back of the seat, preventing him from hitting.

Seat belts are one of the most effective means of protection in an accident.

Therefore, passenger cars must be equipped with seat belts if attachment points are provided for this. The protective properties of belts largely depend on their technical condition. Belt malfunctions, in which the vehicle is not allowed to be operated, include tears and abrasions of the fabric tape of the straps visible to the naked eye, unreliable fixation of the tongue of the strap in the lock or the absence of automatic ejection of the tongue when the lock is unlocked. For inertia-type seat belts, the webbing should be freely retracted into the reel and blocked when the car is moving sharply at a speed of 15-20 km / h. Belts that have experienced critical loads during an accident in which the car body has received serious damage are subject to replacement.

AIRBAGS

One of the most common and effective safety systems in modern cars (after seat belts) are airbags. They began to be widely used already in the late 70s, but it was not until a decade later that they really took their rightful place in the safety systems of most manufacturers' cars.

They are located not only in front of the driver, but also in front of the front passenger, as well as from the sides (in the doors, pillars, etc.). Some car models have their forced shutdown due to the fact that people with heart problems and children may not be able to withstand their false operation.

Today, airbags are commonplace not only in expensive cars, but also in small (and relatively inexpensive) cars. Why are airbags needed? And what are they?

Airbags have been developed for both drivers and front seat passengers. For the driver, the pillow is usually installed on the steering, for the passenger - on the dashboard (depending on the design).

The front airbags are deployed when an alarm is received from the control unit. Depending on the design, the degree of filling of the pillow with gas may vary. The purpose of the front airbags is to protect the driver and passenger from injury by solid objects (engine body, etc.) and glass fragments in frontal collisions.

Side airbags are designed to reduce damage to vehicle occupants in a side impact. They are installed on the doors or in the backs of the seats. In the event of a side impact, external sensors send signals to the central airbag control unit. This makes it possible for some or all of the side airbags to deploy.

Here is a diagram of how the airbag system works:

Studies of the effect of airbags on the likelihood of driver death in frontal collisions have shown that it is reduced by 20-25%.

If the airbags have deployed or been damaged in any way, they cannot be repaired. The entire airbag system must be replaced.

The driver's airbag has a volume of 60 to 80 liters, and the front passenger - up to 130 liters. It is easy to imagine that when the system is triggered, the interior volume decreases by 200-250 liters within 0.04 seconds (see figure), which gives a considerable load on the eardrums. In addition, a pillow flying at a speed of more than 300 km / h is fraught with a considerable danger to people if they are not fastened with a seat belt and nothing delays the inertial movement of the body towards the pillow.

If the car is not comfortable, then after traveling especially for a long distance or in case of standing in traffic jams, it will cause you fatigue and irritation. Russian roads, unfortunately, 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, sound insulation, the convenience of the driver's seat and front passenger seat. We intentionally excluded from our list compact small cars, sports cars and convertibles, which by definition cannot be ideally comfortable due to their size or design features.

Also, having familiarized yourself with the best cars for comfort, you can also find out if these models are, as well as what kind they have by clicking on the photo or model name.

A6 is very convenient and comfortable. A trip in this car will appeal to even the most experienced driver.

This year's new Impala has become a modern large sedan. Spacious interior, comfortable, quiet and pleasant to drive. Draw attention to the large and spacious front seats. They are pleasant to the touch and perfectly support the lower back and unload the back, which allows you to comfortably cover long distances.

One of the best sedans on the market. Space and comfortthe main merit of computer engineersChrysler. The top trim is the best. Management of all functions of the car is very convenient. Various amenities, luxury items and silence during the trip will not let you get tired behind the wheel. The car is especially ideal on the highway, where you will not hear the loud work of the engine and the sound of tires.See also:

The highest comfort is available in the car of the maximum complete set. The cabin is quiet. Noise comes from
climate control ventilation. Also, some noise will bother you for several 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 with lower back support. It is worth noting that it is leather seats that hold your back better than fabric chairs. Plus, cloth-trimmed seats are somewhat stiffer than leather, which can lead to fatigue during long traffic jams.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.
Comfort is maximum. Expensive interior trim pleasantly surprises with its textures. The ES models have very quiet engines and expensive noise insulation. The seats are distinguished by their comfort thanks to their width and balanced softness.Reliability Rating

Lexus LS The flagship sedan provides both driver and passengers with comfort and a relaxing ride over any distance. The LS on the road won't be a problem on any road. Noise isolation is top notch. Absorption of extraneous noise is perfect. The smooth running of the car and excellent handling are the main advantage of this model. All seats are very comfortable and luxurious.

Increasing vehicle comfort

In some cases, the electronic system improves not only some properties of the car, for example, its active safety, but also increases its comfort. An example of such a device is a modern wiper control system. Given this circumstance, in this paragraph only those devices are considered, the main purpose of which is to create comfortable conditions for the driver. Information about devices that primarily serve to improve other technical and operational properties of the vehicle, although they increase comfort, is given in other paragraphs.

The reverse situation is also possible, when electronic devices created as comfort systems have simultaneously improved other properties of the car. So, systems for maintaining a constant speed made it possible to obtain noticeable fuel savings, etc.

Comfort devices contribute to the creation of the best psycho-physiological state of the driver, thereby increasing traffic safety. Therefore, electronic systems that improve the comfort of a vehicle cannot be treated as a luxury. Let's look at this in the following examples.

In areas with a hot climate in high-class cars, for example, the American company Cadillac, Seville, Eldorado, air conditioners are widely used, which provide complete air exchange in the cabin in 15-20 seconds with dehumidification and heating. At an outside air temperature of 54 °C, a temperature of 25 °C is set in the car interior for 10 minutes. The cost of air conditioners reaches 10% of the cost of the car.

The Cedric-Gloria car of the Nissan concern is equipped with a modern air conditioning system in the cabin. The system is designed to automatically stabilize 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 cabin is used as the initial data.

The system consists of two nodes. The unit, installed in the front of the car, is designed to adjust the position of the diffuser for supplying air to the passenger compartment. The unit, located at the rear of the vehicle, automatically regulates the supply of cooled air. The passenger in the rear C-Denier can change the speed of the fan located in the rear of the cabin and adjust the degree of air cooling.

The development of electronic air conditioning control systems was accompanied by 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 for installing the temperature sensor inside the passenger compartment was also a significant difficulty due to the effect of radiation from the walls of the car.

It is no coincidence that the Nissan concern system uses two air temperature sensors inside the cabin.

The operation of the air conditioner requires a lot of energy, therefore, at a low crankshaft speed, usually at idle, turning on the compressor (as well as automatic transmissions) can lead to engine overheating or stop it. There are several ways to solve this problem. The simplest is to automatically turn off the compressor clutch at a low engine speed. In more complex systems, an automatic electronic device is installed that allows the engine to increase torque when an additional load is turned on as a result of adjusting the ignition timing.

And here is another device. Many drivers, due to lack of time, neglect the correct setting of the seat position. The degree of discrepancy between the characteristics of the seat and the features of the constitution of the driver is reflected not only in the well-being of a person, but also in the rate of increase in fatigue, i.e., ultimately, 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 changing the adjustment.

The principle of the system is simple. There are four electric motors on the seat frame that change the backrest position and seat height, cushion tilt and seat-to-front panel distance. The driver, by pressing the appropriate buttons, controls the electric motors and finds the most comfortable position for himself. After the selection is completed, the specific button must be pressed. At the same time, from four potentiometers connected to electric motors, digitized data corresponding to a given seat position are entered into the memory device.

The memory device can fix 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. This activates relays that supply power to the electric motors, which change the position of the seat until it reaches the preset settings 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 the storage device is supplied with voltage from the vehicle battery. After disconnecting the battery, it is necessary to re-arrange the input of data on the desired positions into the memory.

This disadvantage is deprived of a similar system installed on the Lagonda car. The system has ’six buttons to control the position of the seat: adjust the height, distance from the instrument panel and tilt the seatback. Two buttons are used to memorize the two best positions, which remain in memory after the power supply is turned off.

In some cases, for example, when driving on a road with low traffic intensity, the driver tries to maintain a constant speed. This problem can be successfully solved with the help of a device for maintaining a constant speed (UPPS) movement.

Modern devices of this type include a device developed by Bosch and installed on Audi-5000 cars of the Volkswagen concern. The driver, by pressing the button on the turn signal lever, gives the command to the car to move with a constant acceleration equal to 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 moves at the required speed and further acceleration is not needed, you can press and immediately release the button.

UPPS allows you to press the throttle control pedal to increase 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 UPSS, simply press the brake pedal. Speed ​​stabilization error does not exceed 2 km/h for the entire range of engine power output.

To reduce the possibility of unintentional switching on, the device reacts to pressing the button only at speeds greater than 30 km/h. The UPS has overload protection. It will automatically turn off when a certain temperature is exceeded.

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 set and actual speed, the electric motor is switched on, changing the position of the throttle valve. In cars with powerful engines, instead of an electric drive, vacuum devices are usually used to turn the throttle.

To Category: - Car Electronics

The study of the working conditions of drivers indicates the significant importance of the parameters of the internal environment in the car. These parameters only with greater or lesser probability correspond to the established standards, which allows us to extend the concept of reliability to the system that provides the conditions for the habitability of people in a car.

In some cases, operational observations are indirect evidence of its insufficient reliability. According to the results of a survey of 4 drivers of this car on the influence of internal environmental factors, the temperature regime in the cab was negatively assessed (hot in summer, cold in winter) - 75% of drivers; the presence of toxic substances (air pollution with exhaust gases) - 75%; influence of vibrations - 75%, noise - 75%.

Abnormal climatic conditions in the car cabin have a harmful 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 temperature in the cab, the driver's attention is dulled, visual acuity decreases, reaction time increases, fatigue sets in quickly, errors and miscalculations appear that can lead to an accident.

A survey was also conducted on the state of noise in the car interior and 100% of the respondents stated the presence of mid-frequency noise from the low quality of the interior plastic, which causes increased irritation during the trip, although they do not exceed noise class 2 according to GOST R 51616 - 2000.

Based on the above, I conclude that the driver's comfort in the car is significantly low, which leads to a decrease in the active safety of the car.

3. Vehicle passive safety systems

Passive safety includes many elements, and one of the main ones is the seat belt. The second most important element of passive safety is the car body. Its front or rear part should, by crushing, dissipate the released impact energy as much as possible, and the central part of the body should provide as much space as possible for the passengers of the car to survive. Interior materials should not only be pleasant to the touch and pleasing to the eye, if necessary, they should soften the blow as much as possible. At the same time, they should not crack, so that their fragments do not cause additional damage to passengers.

After the impact, the car's gas tank must not ignite or crack in order to avoid spilling fuel on the road. Great importance is attached to doorways and locks. As accident statistics show, the most severe injuries, often incompatible with life, are received by passengers who fell out of the opened car doors. At the same time, after an accident, locks and doors should open easily without the use of additional equipment to ensure quick and timely evacuation of people in the cabin.

Composed of a number of factors, often contradictory, passive safety serves to achieve one main task - in the event of an accident, regardless of its severity, do everything possible to save the lives of people in the car.

Based on the study of the safety of the ZAZ 1102 car by the magazine Autoreview No. 3 of 2004. "The hood as a murder weapon"

(A crash test of this car was carried out. The nature and severity of the damage received by Tavria left no doubt about the outcome of the collision for this car.

The front part of Tavria was thoroughly crumpled - 62 cm on the left side. At the same time, the entire front part noticeably shifted to the left, two solid folds appeared on the roof - the body went like a screw. The windshield shattered and flew out from the impact, the driver's door jammed in the opening.

The base of the A-pillar shifted back by 33 cm, to which the spare wheel contributed - it advanced part of the engine shield into the cabin, and the hard plastic instrument panel shifted back and cracked slightly to the left of the center, forming sharp injury-prone edges. With the steering column and the driver's seat, miracles happened at all. The column went to the right so that the steering wheel was almost in the middle and at the same time moved inward by 14 cm. The left seat moved forward by 13 cm, and in addition it was strongly skewed to the left. This happened due to the fact that the power structure of the floor of the body in the area of ​​\u200b\u200bfastening the front seats turned out to be too flimsy - the floor went in waves, bent the seat slide, and they opened up without holding the seat. Together with the deformation of the floor, this reduced the space for the feet and legs, and in addition, after the mannequin bounced back, his head missed the headrest, which is fraught with damage to the cervical vertebrae.

It is also unpleasant that the locks-latches of the rear seat back from the impact opened up and allowed it to fold. The decoded data from the dummy's sensors showed that the total level of overloads that acted on the dummy's head for 20 ms turned out to be higher than the permissible one.)

Imagine our surprise when, while watching high-speed filming, we saw a strange and terrible picture: the hard object that the driver hit his head turned out to be ... the hood! Even during the first inspection of the body, we noticed that the emergency latch of the hood on the left side did not work. The right hook did its job, and the left hook just came off "with meat" upon impact! In general, this is not surprising - the hook is cantilevered to the motor shield, and in the event of a collision, all spot welding points (there are four of them) worked to break away. The hook came off already after 30 milliseconds, and over the next 60 ms, the sharp edge of the hood pierced the windshield, which led to its sweeping out of the opening and shifted into the cabin towards the dummy. The high-speed filming footage clearly shows how the mannequin hit its face on the sharp edge of the hood. And this despite the fact that the belts were tightened as much as is hardly possible during normal driving.

An analysis of the residual deformation of the car body showed that Tavria has a weaker power structure of the body, seat and steering column.