Stair Climbing Robot

1#include <AFMotor.h>
2//initial motors pin
3AF_DCMotor motor1(1, MOTOR12_1KHZ);
4AF_DCMotor  motor2(2, MOTOR12_1KHZ);
5AF_DCMotor motor3(3, MOTOR34_1KHZ);
6AF_DCMotor motor4(4,  MOTOR34_1KHZ);
7
8char command;
9void setup()
10{
11  Serial.begin(9600);  //Set the baud rate to your Bluetooth module.
12}
13void loop(){
14  if(Serial.available()  > 0){
15    command = Serial.read();
16    Stop(); //initialize with motors stopped
17    //Change pin mode only if new command is different from previous.
18    //Serial.println(command);
19    switch(command){
20    case 'F':
21      forward();
22      break;
23    case  'B':
24       back();
25      break;
26    case 'L':
27      left();
28      break;
29    case 'R':
30      right();
31      break;
32 }
33  }
34  void forward()
35{
36  motor1.setSpeed(255); 
37  motor1.run(FORWARD); 
38  motor2.setSpeed(255); 
39  motor2.run(FORWARD); 
40  motor3.setSpeed(255);
41  motor3.run(FORWARD);
42  motor4.setSpeed(255);
43  motor4.run(FORWARD);
44}
45void back()
46{
47  motor1.setSpeed(255);  
48  motor1.run(BACKWARD); 
49  motor2.setSpeed(255); 
50  motor2.run(BACKWARD);  
51  motor3.setSpeed(255); 
52  motor3.run(BACKWARD); 
53  motor4.setSpeed(255);  
54  motor4.run(BACKWARD); 
55}
56void right()
57{
58  motor1.setSpeed(255);  
59  motor1.run(BACKWARD); 
60  motor2.setSpeed(255); 
61  motor2.run(BACKWARD);  
62  motor3.setSpeed(255); 
63  motor3.run(FORWARD);  
64  motor4.setSpeed(255);  
65  motor4.run(FORWARD);  
66}
67void left()
68{
69  motor1.setSpeed(255);  
70  motor1.run(FORWARD); 
71  motor2.setSpeed(255); 
72  motor2.run(FORWARD);  
73  motor3.setSpeed(255); 
74  motor3.run(BACKWARD); 
75  motor4.setSpeed(255);  
76  motor4.run(BACKWARD); 
77}
78void Stop()
79{
80  motor1.setSpeed(0); 
81  motor1.run(RELEASE); 
82  motor2.setSpeed(0); 
83  motor2.run(RELEASE); 
84  motor3.setSpeed(0); 
85  motor3.run(RELEASE);
86  motor4.setSpeed(0); 
87  motor4.run(RELEASE);  
88}
89