stm32f103c8t6用pid算法控制五路循迹小车

首先，需要确定五路循迹小车的传感器类型和数量。常见的循迹传感器有红外线传感器和光电传感器，数量一般为5路或7路。然后，需要对传感器进行数据采集和处理，计算出车子的偏差值。最后，使用PID算法计算出控制量，通过PWM信号控制电机转速，使小车实现自动循迹。下面是一个简单的PID控制代码示例：

#include <stdio.h>
#include "stm32f10x.h"

#define LEFT_MOTOR_PIN GPIO_Pin_0
#define RIGHT_MOTOR_PIN GPIO_Pin_1
#define LEFT_SENSOR_PIN GPIO_Pin_2
#define RIGHT_SENSOR_PIN GPIO_Pin_3

#define KP 1.0
#define KD 0.1
#define KI 0.01

float error = 0, last_error = 0, integral = 0;
float setpoint = 0; //设定值，即车子应该在循迹线上的位置
float output = 0; //输出值，即PWM信号的占空比

void TIM2_IRQHandler(void)
{
    if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET) {
        //获取传感器数值
        int left_sensor_value = GPIO_ReadInputDataBit(GPIOA, LEFT_SENSOR_PIN);
        int right_sensor_value = GPIO_ReadInputDataBit(GPIOA, RIGHT_SENSOR_PIN);
        //计算偏差值
        float error = (left_sensor_value - right_sensor_value) * 0.5;
        //计算PID控制量
        float derivative = error - last_error;
        integral += error;
        last_error = error;
        output = KP * error + KD * derivative + KI * integral;
        //控制电机转速
        if (output > 0) {
            TIM_SetCompare1(TIM3, output);
            TIM_SetCompare2(TIM3, 0);
        } else {
            TIM_SetCompare1(TIM3, 0);
            TIM_SetCompare2(TIM3, -output);
        }
        //清除中断标志位
        TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
    }
}

int main(void)
{
    //初始化GPIO和PWM
    GPIO_InitTypeDef GPIO_InitStructure;
    TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
    TIM_OCInitTypeDef TIM_OCInitStructure;

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE);
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);

    GPIO_InitStructure.GPIO_Pin = LEFT_MOTOR_PIN | RIGHT_MOTOR_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    GPIO_InitStructure.GPIO_Pin = LEFT_SENSOR_PIN | RIGHT_SENSOR_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    TIM_TimeBaseStructure.TIM_Period = 1999;
    TIM_TimeBaseStructure.TIM_Prescaler = 71;
    TIM_TimeBaseStructure.TIM_ClockDivision = 0;
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);

    TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
    TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
    TIM_OCInitStructure.TIM_Pulse = 0;
    TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
    TIM_OC1Init(TIM3, &TIM_OCInitStructure);
    TIM_OC2Init(TIM3, &TIM_OCInitStructure);

    TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
    TIM_Cmd(TIM3, ENABLE);
    TIM_Cmd(TIM2, ENABLE);

    NVIC_InitTypeDef NVIC_InitStructure;
    NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    while (1) {
        //等待中断处理
    }
}

需要注意的是，这只是一个简单的示例代码，实际应用中需要根据具体情况进行修改和优化。同时，需要谨慎调整PID参数，避免出现震荡和不稳定的情况。