Structural Synthesizing of Intellectual Systems of Automobile Active Safety 2000-01-1637
In modern automotive industry is reshaped the new class of devices - intellectual systems of active safety (SAS). Their problem is safety control of the automobile movement by adequate reacting on suddenly changed road conditions and driver operating. The reliability of operation and the correctness of solutions for SAS are built up at the stage of its designing by synthesizing flexible, stable algorithm and creation of the informational-executive instrumentation for the intellectual control by automobile wheel.
The statistical analysis of the friction arguments in the system “wheel - road”, held by the writers, has allowed to work out concept of preextreme control for SAS, which one makes possible to adapt for a flowing state of a road adjustment process by move of a wheel in the field of small slip (s=0,01 … 0,1). At the expense of this slip area is possible to avoid loss of controllability even at availability of a side withdrawal of a wheel. Simultaneously can be realized the high efficiency of the braking or acceleration, which one is characterized by usage of the wheel friction at a level not less than 80 … 85 %.
The structure of an algorithmic part of SAS is formed on the basis of proposed concept, in which one as argument of regulation can be used the wheel slip, its derivative and resultant moment from forces in the road-wheel-contact. Dynamic operational analysis of a wheel in SAS-composition has shown, that exterior perturbations in system requiring the polices at regulation, arise at variation of wheel load, speed by the beginning of regulations and friction of a wheel. The SAS-pattern includes a multithread optical pickup of the wheel speed permitting to receive the information on wheel slip and its derivative with indispensable fidelity and sensor of brake force, bound with a slide of brake gear. The adapting of SAS to the probable driver operating is carried out through an intellectual food of brake control. The modulating of brake pressure in wheels is made within integrated blocks “microprocessor control unit - modulator - built-in pressure units”, which are realized the control algorithms by means of the CAN channel. In operation gives the structural diagram of SAS and its description.