Arduino UNO
Cytron 2 Amp Motor Driver Shield
LSS05 sensor
11.1V LiPo battery
Upon uploading the sketch (I got it from the Edubot tutorial) and test the robot. It going too fast, is this because of LiPo battery that I used? Do I need to "step down" the voltage?
I've also tried to use coding below (PID) and could anyone advise on how to modify the code so that it can be used with this shield?
- CODE: SELECT_ALL_CODE
float Kp=0,Ki=0,Kd=0;
float error=0, P=0, I=0, D=0, PID_value=0;
float previous_error=0, previous_I=0;
int sensor[5]={0, 0, 0, 0, 0};
int initial_motor_speed=100;
void read_sensor_values(void);
void calculate_pid(void);
void motor_control(void);
void setup()
{
pinMode(9,OUTPUT); //PWM Pin 1
pinMode(10,OUTPUT); //PWM Pin 2
pinMode(4,OUTPUT); //Left Motor Pin 1
pinMode(5,OUTPUT); //Left Motor Pin 2
pinMode(6,OUTPUT); //Right Motor Pin 1
pinMode(7,OUTPUT); //Right Motor Pin 2
Serial.begin(9600); //Enable Serial Communications
}
void loop()
{
read_sensor_values();
calculate_pid();
motor_control();
}
void read_sensor_values()
{
sensor[0]=digitalRead(A0);
sensor[1]=digitalRead(A1);
sensor[2]=digitalRead(A2);
sensor[3]=digitalRead(A3);
sensor[4]=digitalRead(A4);
if((sensor[0]==0)&&(sensor[1]==0)&&(sensor[2]==0)&&(sensor[4]==0)&&(sensor[4]==1))
error=4;
else if((sensor[0]==0)&&(sensor[1]==0)&&(sensor[2]==0)&&(sensor[4]==1)&&(sensor[4]==1))
error=3;
else if((sensor[0]==0)&&(sensor[1]==0)&&(sensor[2]==0)&&(sensor[4]==1)&&(sensor[4]==0))
error=2;
else if((sensor[0]==0)&&(sensor[1]==0)&&(sensor[2]==1)&&(sensor[4]==1)&&(sensor[4]==0))
error=1;
else if((sensor[0]==0)&&(sensor[1]==0)&&(sensor[2]==1)&&(sensor[4]==0)&&(sensor[4]==0))
error=0;
else if((sensor[0]==0)&&(sensor[1]==1)&&(sensor[2]==1)&&(sensor[4]==0)&&(sensor[4]==0))
error=-1;
else if((sensor[0]==0)&&(sensor[1]==1)&&(sensor[2]==0)&&(sensor[4]==0)&&(sensor[4]==0))
error=-2;
else if((sensor[0]==1)&&(sensor[1]==1)&&(sensor[2]==0)&&(sensor[4]==0)&&(sensor[4]==0))
error=-3;
else if((sensor[0]==1)&&(sensor[1]==0)&&(sensor[2]==0)&&(sensor[4]==0)&&(sensor[4]==0))
error=-4;
else if((sensor[0]==0)&&(sensor[1]==0)&&(sensor[2]==0)&&(sensor[4]==0)&&(sensor[4]==0))
if(error==-4) error=-5;
else error=5;
}
void calculate_pid()
{
P = error;
I = I + previous_I;
D = error-previous_error;
PID_value = (Kp*P) + (Ki*I) + (Kd*D);
previous_I=I;
previous_error=error;
}
void motor_control()
{
// Calculating the effective motor speed:
int left_motor_speed = initial_motor_speed-PID_value;
int right_motor_speed = initial_motor_speed+PID_value;
// The motor speed should not exceed the max PWM value
constrain(left_motor_speed,0,255);
constrain(right_motor_speed,0,255);
analogWrite(9,initial_motor_speed-PID_value); //Left Motor Speed
analogWrite(10,initial_motor_speed+PID_value); //Right Motor Speed
//following lines of code are to make the bot move forward
/*The pin numbers and high, low values might be different
depending on your connections */
digitalWrite(4,HIGH);
digitalWrite(5,LOW);
digitalWrite(6,LOW);
digitalWrite(7,HIGH);
}