/segbotler self balancing robot 2013
//Austin Dovel

#include
int x, r, l, s, f, xa, xb, xc;

//Digital pin 13 is serial transmit pin to sabertooth
#define SABER_TX_PIN  13
//Not used but still initialised, Digital pin 12 is serial receive from Sabertooth
#define SABER_RX_PIN  12
//set baudrate to match sabertooth dip settings
#define SABER_BAUDRATE  9600
SoftwareSerial SaberSerial = SoftwareSerial (SABER_RX_PIN, SABER_TX_PIN );

void initSabertooth (void)  {
  //communicate with sabertooth
pinMode ( SABER_TX_PIN, OUTPUT );
SaberSerial.begin( SABER_BAUDRATE );
}

void setup()                    // run once, when the sketch starts
{
  initSabertooth();
    //analogINPUTS
    Serial.begin(9600);  
}

void set_motor()   {
  x = analogRead(0);       // read analog input pin 0

//x range is about 270-400 and flat is about 330
       
//smooth x by averaging 3 readings of x
xa = x;
delay (20);
x = analogRead(0);     
xb = x;
delay (20);
x = analogRead(0);      
xc = x;
x= (xa +xb + xc)/3;

         
//SABER_right_FULL_FORWARD 127
//SABER_right_FULL_REVERSE 1
//SABER_left_FULL_FORWARD 255
//SABER_left_FULL_REVERSE 128

//s=slope with less being more aggressive
s = 1.8  ;
//f=fudge factor
f = 5;


//stable x around 330
if ((x > 325) && (x < 335)) {
r = 62;
l = 194;
}
//drive forward at a steady speed if leaning forward a little 310 > x < 330
if ((x > 310) && (x < 326)) {
r = 45;
l = 167;
}
//if falling forward more increase speed linearly for 279 > x < 311
if ((x > 279) && (x < 311)) {
//higher values make it faster
r = s * x - 278 + f;
l = s * x - 148 + f;
}
//if full forward x < 280
if ((x > 250) && (x < 280)) {
r = 6;
l = 133;
}
// drive backward at a steady speed if leaning back a little 334 > x > 349
if ((x > 334) && (x < 349)) {
r = 78;
l = 208;
}
//if falling backwords more increase speed linearly for 348 < x < 390
if ((x > 348) && (x < 391)) {
//lower values make it faster
r = s * x - 270 + f;
l = s * x - 140 + f;
}
//if full backwords 390 < x
if ((x > 390) && (x < 410)) {
r = 122;
l = 250;
}

//send motor outputs to sabertooth
SaberSerial.write(byte(r));
SaberSerial.write(byte(l));

}

void loop ()  {
 
float level = 0;

int u;

  set_motor();
 
} // end loop