Nico De Witte / racing_robots

Racing Robots Session

Dependencies:   MbedJSONValue m3pi

This is the library for the Racing Robots session. It supports the M3PI robot of Polulu.

It is based on the "Arduino" principle of the init and loop function.

Just add a main.cpp file which contains:

Racing Robots main file

#include "robot_logic.h"

void init()
{
   //put your initialization logic here
}

void loop()
{
    //put your robot control logic here    
}

Features include:

  1. Controlling the LEDS
  2. Move forward and backward
  3. Turn
  4. Read the sensor values
  5. Use a PID controller

robot_logic.h

Committer:
sillevl
Date:
2015-06-01
Revision:
9:0385d1bfc38b
Parent:
8:597ce8a7d34b

File content as of revision 9:0385d1bfc38b:

#ifndef H_ROBOT_LOGIC
#define H_ROBOT_LOGIC

#include "mbed.h"
#include "m3pi.h"

typedef enum {
   LED_1 = 0,
   LED_2 = 1,
   LED_3 = 2,
   LED_4 = 3,
   LED_5 = 4,
   LED_6 = 5,
   LED_7 = 6,
   LED_8 = 7
} LedIndex;

typedef enum {
    LED_ON = 0,
    LED_OFF = 1,
    LED_TOGGLE = 2
} LedState;


/**
 * Drive the robot forward or backward.
 * If the robot was turning it will stop turning and drive in a straight line.
 *
 * @param speed The speed percentage with which to drive forward or backward.
 * Can range from -100 (full throttle backward) to +100 (full throttle forward).
 */
void drive(int speed);

/**
 * Turn the robot left or right while driving.
 *
 * @param turnspeed The percentage with which to turn the robot.
 *          Can range from -100 (full throttle left) to +100 (full throttle right).
 */
void turn(int turnspeed);

/**
 * Stop the robot.
 */
void stop(void);

/**
 * Calibrate the line follow sensors.
 * Take note that the robot should be placed over the line
 * before this function is called and that it will rotate to
 * both sides.
 */
void sensor_calibrate(void);

/**
 * Read the value from the line sensor. The returned value indicates the
 * position of the line. The value ranges from -100 to +100 where -100 is
 * fully left, +100 is fully right and 0 means the line is detected in the middle.
 *
 * @return The position of the line with a range of -100 to +100.
 */
int line_sensor(void);

/**
 * Initialize the PID drive control with
 * the P, I and D factors.
 *
 * @param p The P factor
 * @param i The I factor
 * @param d The D factor
 */
void pid_init(int p, int i, int d);

/**
 * Determine PID turnspeed with which the robot should
 * turn to follow the line at the given position.
 *
 * @param line_position The position of the line in a range of [-100, +100]
 *
 * @return The turnspeed in a range of [-100, +100]
 */
int pid_turn(int line_position);

/**
  *Show speed, turn and sensor data on the LCD
  */
void show_stats();

/**
 * Shows the name of the robot on the display.
 *
 * @param name C character string (null-terminated) with the name of the robot (max 8 chars)
 */
void show_name(char * name);


/**
  * Turn on, off or toggle a specific LED
  * @param i the LED number LED_0 .. LED_7
  * @param state the LED state LED_ON, LED_OFF, LED_TOGGLE 
  * @example led(LED_0, LED_ON); turns LED 0 on.
  */
void led(LedIndex i, LedState state);

/**
 * Wait for an approximate number of milliseconds.
 *
 * @param milliseconds The number of milliseconds to wait.
 */
void await(int milliseconds);

/**
 * If using Xbee to start/stop the robot, you can set a unique code to prevent starting or stopping other robots.
 * To start or stop the robot, send the a json string only containing a "start" or "stop" key with the code as a value.
 * eg: {"start": 1234} will start the robot with code set to 1234, {"stop": 9876} will stop the robot with code 9876.
 *
 * @param code A number between 0 and 1000.
 */
void setCode(int code);

/**
 * Use this method if you need to know if something (eg: Xbee) is preventing the robot from driving
 * 
 * @return Boolean true if the robot can drive, false if the robot cannot drive
 */
int canDrive();

#endif