Diff: LIDAR.h

Revision:

0:b5c7dc5f1fc8

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/LIDAR.h	Mon Oct 02 06:03:22 2017 +0000
@@ -0,0 +1,117 @@
+#ifndef MBED_LIDAR_H
+#define MBED_LIDAR_H
+
+#include "mbed.h"
+
+/** A Library used to read data from Low-cost NEATO LIDAR
+ *
+ * Example:
+ * @code
+ * #include "mbed.h"
+ * #include "LIDAR.h"
+ * 
+ * int main() {
+ *   // The tx pin is PC_10
+ *   // The rx pin is PC_11
+ *   // The PWM pin to control motor is PA_15
+ *   LIDAR lidar (PC_10, PC_11, PA_15);
+ *  
+ *   // Activate serial to PC for debugging
+ *   Serial pc(USBTX, USBRX);
+ *
+ *   // Set duty cycle for motor PWM
+ *   lidar.SetDuty(0.25);
+ *
+ *   // Start data aquisition
+ *   lidar.StartData();
+ *
+ *   while (1) {
+ *       // Aquire LIDAR data from angle 0, 45, 90, 135... 315
+ *       // Then send it to serial PC with 9600 baud
+ *       data = lidar.GetData(i);
+ *       speed = lidar.GetSpeed();
+ *       pc.printf("Spd=%.1f; D[%d]=%.1f\n", speed, i, data);
+ *       i += 45;
+ *       if(i >= 360) i = 0;
+ *       wait(0.5);
+ *   }
+ * }
+ * @endcode
+ */
+class LIDAR {
+
+public:
+    /** Create an LIDAR object connected to the specified serial port and 
+     *  PWM port for LIDAR motor control
+     *
+     * @param tx Transmit pin
+     * @param rx Receive Pin
+     * @param motor_pwm PWM pin for motor control 
+     *
+     * @note
+     *   The LIDAR will be initiated with 1kHz PWM with 0% duty-cycle
+     *   and 115200 baud (standard baud for NEATO LIDAR)
+     */
+    LIDAR(PinName tx, PinName rx, PinName motor_pwm);
+    
+    /** Start data aquisition after setting up other initial parameter
+     *  such as motor duty cycle and period.
+     *
+     * @note
+     *   This function will activate Rx interrupt each time data is received
+     */
+    void StartData(void);
+    
+    /** Stop data aquisition
+     *
+     * @note
+     *   This function will deactivate Rx Interrupt
+     */
+    void StopData(void);
+    
+    /** Set the PWM duty cycle precentage for LIDAR motor
+     *
+     * @param duty The duty cycle ranged from 0.0(0%) to 1.0(100%) 
+     *
+     */
+    void SetPWMDuty(float duty);
+    
+    /** Set the PWM duty cycle for LIDAR motor in microseconds. The
+     *  generated frequency will be f = 1000000/period
+     *
+     * @param microseconds The PWM period in microseconds 
+     *
+     */
+    void SetPWMPeriodUs(int microseconds);
+    
+    /** Obtain the distance data read by LIDAR in certain angle
+     *
+     * @param degree The angle where the data want to be read, it is integer ranged from 0-359  
+     *
+     * @return Distance data in cm
+     */
+    float GetData(int degree);
+    
+    /** Obtain the rotation speed of LIDAR motor
+     * 
+     * @return Speed data in rpm
+     */
+    float GetSpeed(void);
+
+private:
+    Serial _lidar;
+    PwmOut _motor;
+    
+    short _data[360];
+    char* _data_ptr;
+    unsigned short _speed;
+    char* _speed_ptr;
+    
+    char _fsm_state;
+    char _fsm_count;
+    unsigned short _fsm_angle;
+    
+    void data_parser(void);
+};
+
+#endif
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