SU787218A1 - Method of controlling the transitory process of vehicle wheel rolling - Google Patents

Description

(54) METHOD OF MANAGING THE TRANSITION PROCESS OF ROLLING A CAR WHEEL The invention relates to the combined control of several vehicle assemblies, in particular, anti-lock braking of an automobile in connection with engine management or transmission. A known method for controlling the transitional process of rolling a car wheel is to change the braking torque applied to the wheel in accordance with the adhesion conditions. The pre-wheel adhesion conditions are estimated in advance by the amount of steering wheel angle. one of the factors for reducing the clutch margin ClJ. The disadvantage of this method is that it cannot be used in areas of linear motion. The closest to the proposed by the technical essence is the method of controlling the transition process of the rolling wheel of a car, which consists in changing the torque and brake torques applied to the wheel in accordance with the adhesion conditions detected by measuring the parameters of this rolling transition process and the results of a preliminary assessment of the same conditions of adhesion by the previous transition process. For example, if the parameters of the rolling transition when pressing the accelerator pedal correspond to slipping on a slippery road, then the braking process after such slipping is controlled with respect to the slippery road from the very beginning, i.e. not waiting for wheel locking or other low clutch manifestations during the current braking; further braking is carried out, focusing on the arrival of signals on the results of measurements of the parameters of the braking process I. This method, however, is adapted only for foot control, and is not applicable in automatic control. The purpose of the invention is to increase the control efficiency by increasing the speed of adaptation of the control to the current adhesion conditions with automatic regulation. This goal is achieved by the fact that the results of a preliminary assessment of the conditions of adhesion by the previous

the transient is taken into account in the period determined by the expected duration of the preservation of the adhesion conditions and at the first change of the torque or braking moments applied to the wheel after the established rolling mode.

The drawing shows a diagram of an apparatus for implementing this control method.

A device for implementing the proposed method consists of a clutch condition analyzer, which includes a source 1 of clutch condition information and a key corrector 2. This analyzer generates commands to control the drive pressure for the brake. The information source 1 contains a slippage detector 3 (for example, a differentiating device). Detector 3 is connected by a memory element 4, the charge of which is able to lock the equalizer key 2 connected to the memory element. Source 1 also contains a resistor 5 driven by steering body 6. The resistor 5 is connected to the unit of rotational speed 7, the wheel and to the inverting input of the adder 8, another input of which is connected to the output of the unit 7. Switch 9 is connected to the brake pedal and can connect the wheel speed sensor to either the unit 7 and the resistor J or to the skidding detector . To reset the information taken into account, i.e., to exclude the use of information on measurement results (or a rough estimate) of the transient parameters beyond the expected duration of the adhesion conditions and to implement the release of the wheel, respectively, a key 10 constituting the discharge circuit connected to the element 4 memory and threshold logic circuit 11.

If as a result of excessive opening of the engine throttle the wheel slips, this indicates that the traction conditions acting on the wheel torque do not match, and the skidding parameter (angular acceleration of the wheel in this case is a qualitative sign of the indicated discrepancy resulting from turning an excessively small radius In the case of subsequent short braking under the same conditions, for example for a period of a few seconds, the drive train should be limited. in order to avoid wheel blocking. In this case, a significant acceleration of the wheel rotation is detected by the detector 3, which charges memory element 4. The element 4, in turn, locks the key 2 of the equalizer. wheel speed adjuster 7 to adder 8 (until key 2 was locked, input of adder 8 was short-circuited with key 2). Turning the car (reduction factor of adhesion) is a sign of deteriorating wheel adhesion conditions. This feature appears before the start of the wheel rolling transition control and is also taken into account in advance due to the drive of the resistor 5 from the steering control body 6 of the information source 1.

Decreasing the resistance of the resistor 5 prepares the underestimation of the wheel speed signal for the inverting input of the adder 7. Therefore, both under the influence of the steering and due to the fact of the wheel slip, the sensitivity of the analyzer is generally increased relative to the reference signal that can be fed to the inverting input of the adder 8 from the setting side 7 in the case of braking. At this input, the reference signal will be compared with the signal from the resistor 5. If you press the brake pedal shortly after of the described events, the response of the contact group of the switch 9, the detector 3 stops receiving information from the wheel, and the charge of the memory element 4 keeps the key 2 in the open state. The wheel speed setting device 7 at the moment of contact group operation of the switch 9 is charged through these contacts and outputs to the adder 8 a complete signal proportional to the speed of the car (or the speed of the wheel slipping if the slip has not stopped). Due to the predominance of such a signal over the rotational speed signal lowered at the inverting input, a pulse occurs at the output of the adder B. This impulse causes the logic circuit 11 to be triggered, at the command of which the wheel automatically disbrakes. At the same time, the key 10 is also open, resetting the charge of the element 4, thereby removing all the preliminary correction at the first application of the brake element to the wheel (except for the correction by resistor 5, which remains for the whole period of the turn). The further braking process is carried out in a known manner, as in the anti-lock braking systems, due to the simplest simulation of the speed of the car by the incident charge of the driver 7.

If from the wheel slip to the start of braking, there is a long enough time for the advance information to lose its value, for example, more

Claims (1)

Claim 5 A method for controlling the rolling process of a vehicle’s wheel rolling, which consists in changing the torque and braking torque applied to the wheel in accordance with the friction conditions • 0 identified by measuring the parameters of this rolling process and by a preliminary assessment of the friction conditions of the previous transitional process 15, which differs the fact that, in order to improve control efficiency by increasing the speed of adaptation to current clutch conditions with automatic control 20, the result Ata preliminary assessment of the conditions of the previous transient clutch into account in the time interval defined by the expected duration of the conservation conditions of the clutch and the first change ** attached to the wheel torque or braking moments after steady state rolling.