Multifunctional Cruise Control System based on pic24FJ64GA306 OBD Method for Cars

With the popularity of cars, people's understanding of cars gradually changes from riding and transporting to safety, comfort and fuel saving. People have higher and higher requirements for the appearance of the car as well as the safety configuration and comfort configuration of the car.

The fixed speed cruise control system is mainly to free the driver's right foot, people who have driven a car know that when running wildly at high speed, the right foot always has to be on the gas pedal to keep the car moving at a certain speed, after a long drive the driver will feel sore and uncomfortable in the right leg. And manpower to control the throttle strength range is always large, resulting in driving the car fast and slow.

The consumption of fuel consumption is also large, because the relative fuel consumption of the car in the state of equal speed driving is relatively low. The fuel consumption data from the Ministry of Industry and Information Technology was measured at 90 km/h at the same speed.

The cruise control system allows the driver to set the desired driving speed while driving, and after setting, the cruise control system will automatically make the car drive at the set speed. Self-adjustment of the car in the process of travel speed difference, due to the system adjustment speed is very fast, the ride car does not feel the system for the car speed adjustment process in the models produced before 2012 only in the middle and high-end configuration of the model will have a fixed speed cruise function, for the low most of the vehicles are not equipped with a fixed speed cruise function.

Based on the OBD interface of PIC24FJ64GA306, the speed cruise program uses the OBD interface of the original car to go to the control parameters needed for the speed cruise, and through the high-speed operation of PIC24FJ64GA306, the action mechanism of the car is controlled to achieve a closed-loop constant speed control effect, so as to complete the speed function.

►Product physical picture

►Core technology advantage

The OBD cruise control system based on pic24FJ64GA306 uses the original OBD signal to read the speed signal, throttle opening signal and other parameters of the car driving through Canbus or K-line, and the STM32F103 integrates the internal protocol of automotive IEE1939, through which the speed, throttle and other signals can be resolved.

When the driver sets the driving speed of the fixed speed cruise, the pic24Fj64GA306 will compare the value of the fixed speed with the value read from the OBD during driving through the algorithm, and adjust the driving speed through the algorithm to ensure that the car runs at the same speed according to the set speed, so as to free the driver's right foot and reduce fuel consumption. The purpose of freeing the driver's right foot and reducing fuel consumption.

►Specifications

①Reading parameters from OBD interface via Canbus K-line

②Using arm chip to parse IEE1939 protocol

③System takes power from OBD 12V

④System overall running current is less than 100mA

⑤System computing uses XLP's Microchip's high performance 16bit MCU