The sensor in ESP and the circuit that accept ventriloquial method are analytic

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ESP (the electron stabilizes a program) it is the invention of sex of a mark with electronic-controlled car. Orgnaization of different research and development is right of this one system name very much identical, the world that be like rich (BOSCH) the company is inchoate call a car kinetic control (VDC) , rich world, plum is surpassed now heart, run quickly the company calls ESP; Abundant field company calls car stability to control a system (VSC) , car stability support system (VSA) or car electron stability controls a system (ESC) ; BMW company calls kinetic stability to control a system (DSC) . Although the name is endless identical, but it is the car in the tradition kinetic control system, if a transverse and stable controller adds on the foundation of ABS and TCS, pass control transverse with fore-and-aft force distributing and extent, so that control any routes besides the kinetic motion mode of next cars, can improve the dynamical performance of the car below all sorts of operating mode thereby. The circuit that of article introduction is the sensor in ESP and interface technology is analytic: The output of sensor of corner of steering wheel of interface of sensor of corner of circuit principle steering wheel is orthogonal encode pulse. Orthogonality codes pulse includes two pulse series, vicissitudinous frequency and 1/4 cycle (90 ° ) fixed and phasic deflection, if pursue,1 is shown. Through detecting the phasic relation of 2 signal can be judged for clockwise and anticlockwise direction, undertake adding to signal accordingly / reduce count, get current computation accumulative total is worth thereby, also namely the absolutely corner of steering wheel, and the change of corner is led namely angular velocity, can measure through signal frequency piece. Additional, sensor of steering wheel corner has a null to output signal, when position of steering wheel inter, this signal outputs 0V, output 5V otherwise, carry this signal, can undertake online calibration to absolutely corner. Graph if the interface circuit of C164CI of weaveform of alignment of pulse of sensor of corner of 1 steering wheel and sensor of steering wheel corner pursues show 2 times. Piece inside inside the orthogonal decoder that buy increment codes, this decoder use timer cites a base twice of 3 (T3IN, T3EUD) the input that regards orthogonality as pulse, after installing relevant register correctly, the value of the data register of 3 and steering wheel corner become timer direct ratio, the computational corner that reason can go to the lavatory, the sensor of steering wheel corner that article place uses each correspondence 44 pulse, set timer the data register of 3 is T3, absolutely corner is. Graph circuit of interface of sensor of corner of 2 steering wheel undertakes differring separating operation, can get corner change rate. The parameter that small controller receives consideration sends ECU through CAN. Annulus fast introduce partly before sensor interface basis annulus fast sensor signal characteristic, if the graph is shown 3 times,design interface circuit. Pursue 3 rounds fast circuit of sensor interface circuit uses wave of two class filter and plastic, in order to make sure round of fast signal won't be missing below extremely low rotate speed, avert the signal interference that causes because of suspension vibration at the same time. By resistor R2 introduces arrearage of the first class to compare in the graph, and use 74HC14 introduces arrearage of the 2nd class to compare. Yaw angular velocity, fore-and-aft / angular velocity of yaw of transverse acceleration sensor, fore-and-aft / the installation position of transverse acceleration sensor is basic and same, output is the imitate quantity of 0V-5V, because the car is bumpy the signal wave motion that cause is characteristic and consistent, reason is enclosed in same module. If its hardware interface pursues 4 show, realize wave of filter of the buy before hardware imitate, come from the composition of high frequency noise in the imitate signal of sensor in order to restrain, prevent to appear in sampling process mix fold a phenomenon. Adjust a figure 4 in the parameter of each block look component, can install filter wave to end frequency and delay time size. In car moving process, when the travel on better road surface, because signal is better, delay time wants as far as possible small, and in the travel on bumpy road surface, hope filter wave effect is close friends. But once design,end as a result of the frequency character of hardware filter wave, cannot revise in real time, reason needs to design link of digital filter wave in software. The filter of accept having safeguard with digital filter commonly used wave, Ka Erman filter, linear is forecasted implement, wait from applicable filter. What choose maneuver to consider measure performance of small, real time good here is first-order the low wave that connect filter. The graph is 4 yaw angular velocity, fore-and-aft / the structural characteristic that the article discussed ESP system middling to use sensor reachs epilogue of complier of circuit of interface of transverse acceleration sensor signal is characteristic, the signal that designed each sensor handles interface, include hardware interface circuit and software processing plan among them. Designed include yaw angular velocity, fore-and-aft / the compositive module of transverse acceleration sensor, undertake through CAN bus line and ECU data is transmitted, have better interference rejection sex and reliability. CNC Milling CNC Machining