v1.5增加一个舵机控制前档，实现踢球效果。

v1.5/lib/Simple_FOC/src/common/pid.h

@@ -0,0 +1,44 @@
+#ifndef PID_H
+#define PID_H
+
+
+#include "time_utils.h"
+#include "foc_utils.h"
+
+/**
+ *  PID controller class
+ */
+class PIDController
+{
+public:
+    /**
+     *  
+     * @param P - Proportional gain 
+     * @param I - Integral gain
+     * @param D - Derivative gain 
+     * @param ramp - Maximum speed of change of the output value
+     * @param limit - Maximum output value
+     */
+    PIDController(float P, float I, float D, float ramp, float limit);
+    ~PIDController() = default;
+
+    float operator() (float error);
+
+    float P; //!< Proportional gain 
+    float I; //!< Integral gain 
+    float D; //!< Derivative gain 
+    float output_ramp; //!< Maximum speed of change of the output value
+    float limit; //!< Maximum output value
+
+    float error_prev; //!< last tracking error value
+
+protected:
+    //float error_prev; //!< last tracking error value
+    float output_prev;  //!< last pid output value
+    float integral_prev; //!< last integral component value
+    unsigned long timestamp_prev; //!< Last execution timestamp
+};
+
+#endif // PID_H
+
+//Lyf对此进行了修改，将error_prev从protected移至public，便于清楚积分影响