remote | Secret Science Lab

Bao has been taking a break. I think having a robot that moves on its own stresses you out. You’ve been running to flip the off switch after playing with Bao a little. Maybe it’s too much for a 3 year old to deal with. On the plus side, now you know the deal with batteries and recharging, and how Bao gets slow when he’s low on energy. The “energy” and “battery” concept is handy for explaining why you have to eat and sleep.

Anyway, while Bao has been resting, we’ve moved on to the next phase of Bao’s evolution. After some research, I’ve found the perfect recipe. But first, check out the ingredients to see if you can guess what we’re making:

1) LG Optimus Dynamic
This is a $20 prepaid smartphone. Prepaid meaning you can actually buy minutes to use it as a smartphone (e.g. if you need a spare phone for family visiting from out of town). And this one’s nice because it has “triple minutes” for life. So you can buy 200 minutes and the phone will give you 600 minutes magically. But what I’m really buying this for is the hardware and software. It comes packed with the usual sensors: GPS, accelerometer, compass, light sensor; and communication interfaces: Bluetooth, WiFi, PLUS a camera, video recorder, audio recorder, a 1GHz processor, some RAM and 4GB of storage space, AND whatever apps you want and the Android OS to tie it all together. All for $20! In the robot world, each of these devices would cost $20 or more by themselves. But thanks to the economics of smartphones, you can get them ALL for $20. What a wonderful time we live in. I really feel that smartphone tech will accelerate many more industries. (Example: Oculus Rift.) So instead of buying loosey goosey electronics for your robo, the only thing you need is Bluetooth… to pair with a smartphone.

2) Scripting Layer for Android (SL4A)
This is what you install on your Android phone. SL4A lets you tap into every function on your phone from your favorite scripting language (e.g., Python). SL4A can either run a script stored on the phone, or you can connect to SL4A to run a script from your PC. E.g., check this out:

From your PC:



		
		
			
			

			
			import android
droid = android.Android(('192.168.1.3', 53833))
recog = droid.recognizeSpeech().result
droid.ttsSpeak(recog)

			
				
					
				
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						import android
droid = android.Android(('192.168.1.3', 53833))
recog = droid.recognizeSpeech().result
droid.ttsSpeak(recog)
 
					
				
			
		


This tells your phone at 192.168.1.3 to, "Capture what I say, then say it back to me." How crazy is that? (Browse the API to see what else it can do.) You can tell it to take a picture, make a phone call, or even drive a robot... (hint hint)
3) web2py

This is what I used to make a toddler-proof web interface or "app" or GUI. The front-end (View) is HTML/Javascript, and the backend (Controller) is Python -- perfect for hooking up with SL4A. Right now, it doesn't do much. But it still has you rolling on the floor laughing, because I send the words you type to the phone and the phone says them (using SL4A). You've been having fun typing different words to see how the text-to-speech voice screws it up. Anyway, this bomb-proof custom toddler web UI works much better than VI, which we were using earlier...


Oh, and here's my latest IR + Ultrasonic car code. It's tuned for the 3-wheel car and my kitchen:


		
		
			
			

			
			
#include <Makeblock.h>
#include <SoftwareSerial.h>
#include <Wire.h>

MeDCMotor MotorL(M1);  
MeDCMotor MotorR(M2);
MeUltrasonicSensor UltrasonicSensor(PORT_3);
MeInfraredReceiver infraredReceiverDecode(PORT_6);

const boolean g_debug = true;
const int g_stepPeriod = 50;
const int g_maxStepsForward = 3000 / g_stepPeriod;
const int g_maxTurnSteps = 3000 / g_stepPeriod;
const int g_minSpeed = 45;
const float g_leftTrim = .97;
const float g_rightTrim = 1.;

const int LED_PIN = 13;
const int EBRAKE_STOP = 2; // full stop
const int EBRAKE_WAIT = 1; // wait for "Go" signal
const int EBRAKE_GO = 0; // brakes off and GO!
const int MODE_ULTRASONIC = 0;
const int ULTRASONIC_INIT_SPEED = 150;
const int MODE_IR = 1;

int g_speedFactor = 23;
int g_moveSpeed = ULTRASONIC_INIT_SPEED;
int g_numStepsForward = 0;
int g_numTurnSteps = 0;
boolean g_rightFlag;
int g_ebrake = EBRAKE_STOP;
long g_timeLastBlocked = 0;

uint8_t g_mode = MODE_IR;

void setup()
{
  if (g_debug)
    Serial.begin(9600);

  ResetUltrasonic(EBRAKE_STOP);

  infraredReceiverDecode.begin(); 
  pinMode(LED_PIN, OUTPUT); // "obstructed" LED
}

void loop()
{
  if (infraredReceiverDecode.available() || infraredReceiverDecode.buttonState())
  {
    ResetUltrasonic(EBRAKE_GO);
    switch (infraredReceiverDecode.read())
    {
      case IR_BUTTON_PLUS: 
        Forward();
        break;
      case IR_BUTTON_MINUS:
        Backward();
        break;
      case IR_BUTTON_NEXT:
        TurnRight();
        break;
      case IR_BUTTON_PREVIOUS:
        TurnLeft();
        break;
      case IR_BUTTON_TEST:
        ForwardAndLeft();
        break;
      case IR_BUTTON_RETURN:
        ForwardAndRight();
        break;
      case IR_BUTTON_9:
        ChangeSpeed(g_speedFactor*9+g_minSpeed);
        break;
      case IR_BUTTON_8:
        ChangeSpeed(g_speedFactor*8+g_minSpeed);
        break;
      case IR_BUTTON_7:
        ChangeSpeed(g_speedFactor*7+g_minSpeed);
        break;
      case IR_BUTTON_6:
        ChangeSpeed(g_speedFactor*6+g_minSpeed);
        break;
      case IR_BUTTON_5:
        ChangeSpeed(g_speedFactor*5+g_minSpeed);
        break;
      case IR_BUTTON_4:
        ChangeSpeed(g_speedFactor*4+g_minSpeed);
        break;
      case IR_BUTTON_3:
        ChangeSpeed(g_speedFactor*3+g_minSpeed);
        break;
      case IR_BUTTON_2:
        ChangeSpeed(g_speedFactor*2+g_minSpeed);
        break;
      case IR_BUTTON_1:
        ChangeSpeed(g_speedFactor*1+g_minSpeed);
        break;
      case IR_BUTTON_POWER:
        buzzerOn();
        delay(100);
        buzzerOff();
        break;
      case IR_BUTTON_MENU:
        if (g_mode == MODE_IR)
        {
          buzzerOn();
          delay(100);
          buzzerOff();
          delay(100);
          buzzerOn();
          delay(100);
          buzzerOff();
          delay(100);
          buzzerOn();
          delay(300);
          buzzerOff();

          g_mode = MODE_ULTRASONIC;
          g_moveSpeed = ULTRASONIC_INIT_SPEED;
        }
        else
        {
          buzzerOn();
          delay(100);
          buzzerOff();
          digitalWrite(LED_PIN, LOW);

          g_mode = MODE_IR;
        }

        break;
      default:
        break;
    }
  }
  else
  {
    if (g_mode == MODE_IR)
      Stop();
    else if (millis() % g_stepPeriod == 0)
      doUltrasonicCar();
  }
}

void doUltrasonicCar()
{
  int distance = UltrasonicSensor.distanceCm();
  
  boolean isBlocked = (distance > 0 && distance < 60);
  if (isBlocked)
    g_timeLastBlocked = millis();
  else if (millis() - g_timeLastBlocked < 100)
    isBlocked = true;

  if (isBlocked)
    digitalWrite(LED_PIN, HIGH);
  else
    digitalWrite(LED_PIN, LOW);

  boolean isStuck 
    = (g_numTurnSteps > g_maxTurnSteps
      || g_numStepsForward > g_maxStepsForward);

  if (g_ebrake == EBRAKE_STOP && !isBlocked)
  {
    // /unstuck, ready for go signal
    g_ebrake = EBRAKE_WAIT; 
    return;
  }
  else if (g_ebrake == EBRAKE_WAIT && isBlocked)
  {
    // "Go!"
    ResetUltrasonic(EBRAKE_GO);
    return;
  }
  else if (g_ebrake == EBRAKE_GO && isStuck)
  {
    // stuck -- yank ebrake
    g_ebrake = EBRAKE_STOP;
    Stop();
    return;
  }

  if (g_ebrake != EBRAKE_GO)
  {
    // halt until !blocked and receive "Go" signal
    return;
  }
  
  if (isBlocked)
  {
    // evasive maneuvers!
    randomSeed(analogRead(A4));
    int randnum = random(300);

    if (distance > 30)
    {
      if (randnum > 190 && !g_rightFlag)
        TurnLeft();   
      else
        TurnRight();  
    }
    else
    {
      if (randnum > 190) 
        BackwardAndTurnLeft();
      else 
        BackwardAndTurnRight();
    }
  }
  else
  {
    // ONWARD!
    Forward();
  }
}

void ResetUltrasonic(int brakePos)
{
  g_rightFlag = false;
  g_numStepsForward = 0;
  g_numTurnSteps = 0;
  g_ebrake = brakePos;
  
  if (g_debug && g_mode == 0)
    Serial.println("Reset");
}

void Stop()
{
  MotorL.stop();
  MotorR.stop();
  
  if (g_debug)
    Serial.println("Stop");
}

void Forward()
{
  g_numStepsForward++;
  g_numTurnSteps = 0;
  g_rightFlag = false;

  MotorL.run(g_moveSpeed * g_leftTrim);
  MotorR.run(g_moveSpeed * g_rightTrim);
  
  if (g_debug)
    Serial.println("Forward");
}

void ForwardAndLeft()
{
  g_numStepsForward++;
  g_numTurnSteps++;
  g_rightFlag = false;

  MotorL.run(g_moveSpeed / 2);
  MotorR.run(g_moveSpeed);
  
  if (g_debug)
    Serial.println("Forward+Left");
}

void ForwardAndRight()
{
  g_numStepsForward++;
  g_numTurnSteps++;
  g_rightFlag = true;

  MotorL.run(g_moveSpeed);
  MotorR.run(g_moveSpeed / 2);
  
  if (g_debug)
    Serial.println("Forward+Right");
}

void Backward()
{
  g_rightFlag = false;
  g_numTurnSteps = 0;
  MotorL.run(-g_moveSpeed);
  MotorR.run(-g_moveSpeed);
}
void TurnLeft()
{
  g_rightFlag = false;
  g_numStepsForward = 0;
  g_numTurnSteps++;

  MotorL.run(-g_moveSpeed);
  MotorR.run(g_moveSpeed);
  
  if (g_debug)
    Serial.println("Left");
}
void TurnRight()
{
  g_rightFlag = true;
  g_numStepsForward = 0;
  g_numTurnSteps++;

  MotorL.run(g_moveSpeed);
  MotorR.run(-g_moveSpeed);
  
  if (g_debug)
    Serial.println("Right");
}

void BackwardAndTurnLeft()
{
  g_rightFlag = true;
  g_numStepsForward = 0;
  g_numTurnSteps++;

  MotorL.run(-g_moveSpeed/2);
  MotorR.run(-g_moveSpeed);

  if (g_debug)
    Serial.println("Backward+Left");
}
void BackwardAndTurnRight()
{
  g_rightFlag = false;
  g_numStepsForward = 0;
  g_numTurnSteps++;

  MotorL.run(-g_moveSpeed);
  MotorR.run(-g_moveSpeed/2);

  if (g_debug)
    Serial.println("Backward+Right");
}

void ChangeSpeed(int spd)
{
  g_moveSpeed = spd;
}
			
				
					
				
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#include <Makeblock.h>
#include <SoftwareSerial.h>
#include <Wire.h>
 
MeDCMotor MotorL(M1);  
MeDCMotor MotorR(M2);
MeUltrasonicSensor UltrasonicSensor(PORT_3);
MeInfraredReceiver infraredReceiverDecode(PORT_6);
 
const boolean g_debug = true;
const int g_stepPeriod = 50;
const int g_maxStepsForward = 3000 / g_stepPeriod;
const int g_maxTurnSteps = 3000 / g_stepPeriod;
const int g_minSpeed = 45;
const float g_leftTrim = .97;
const float g_rightTrim = 1.;
 
const int LED_PIN = 13;
const int EBRAKE_STOP = 2; // full stop
const int EBRAKE_WAIT = 1; // wait for "Go" signal
const int EBRAKE_GO = 0; // brakes off and GO!
const int MODE_ULTRASONIC = 0;
const int ULTRASONIC_INIT_SPEED = 150;
const int MODE_IR = 1;
 
int g_speedFactor = 23;
int g_moveSpeed = ULTRASONIC_INIT_SPEED;
int g_numStepsForward = 0;
int g_numTurnSteps = 0;
boolean g_rightFlag;
int g_ebrake = EBRAKE_STOP;
long g_timeLastBlocked = 0;
 
uint8_t g_mode = MODE_IR;
 
void setup()
{
  if (g_debug)
    Serial.begin(9600);
 
  ResetUltrasonic(EBRAKE_STOP);
 
  infraredReceiverDecode.begin(); 
  pinMode(LED_PIN, OUTPUT); // "obstructed" LED
}
 
void loop()
{
  if (infraredReceiverDecode.available() || infraredReceiverDecode.buttonState())
  {
    ResetUltrasonic(EBRAKE_GO);
    switch (infraredReceiverDecode.read())
    {
      case IR_BUTTON_PLUS: 
        Forward();
        break;
      case IR_BUTTON_MINUS:
        Backward();
        break;
      case IR_BUTTON_NEXT:
        TurnRight();
        break;
      case IR_BUTTON_PREVIOUS:
        TurnLeft();
        break;
      case IR_BUTTON_TEST:
        ForwardAndLeft();
        break;
      case IR_BUTTON_RETURN:
        ForwardAndRight();
        break;
      case IR_BUTTON_9:
        ChangeSpeed(g_speedFactor*9+g_minSpeed);
        break;
      case IR_BUTTON_8:
        ChangeSpeed(g_speedFactor*8+g_minSpeed);
        break;
      case IR_BUTTON_7:
        ChangeSpeed(g_speedFactor*7+g_minSpeed);
        break;
      case IR_BUTTON_6:
        ChangeSpeed(g_speedFactor*6+g_minSpeed);
        break;
      case IR_BUTTON_5:
        ChangeSpeed(g_speedFactor*5+g_minSpeed);
        break;
      case IR_BUTTON_4:
        ChangeSpeed(g_speedFactor*4+g_minSpeed);
        break;
      case IR_BUTTON_3:
        ChangeSpeed(g_speedFactor*3+g_minSpeed);
        break;
      case IR_BUTTON_2:
        ChangeSpeed(g_speedFactor*2+g_minSpeed);
        break;
      case IR_BUTTON_1:
        ChangeSpeed(g_speedFactor*1+g_minSpeed);
        break;
      case IR_BUTTON_POWER:
        buzzerOn();
        delay(100);
        buzzerOff();
        break;
      case IR_BUTTON_MENU:
        if (g_mode == MODE_IR)
        {
          buzzerOn();
          delay(100);
          buzzerOff();
          delay(100);
          buzzerOn();
          delay(100);
          buzzerOff();
          delay(100);
          buzzerOn();
          delay(300);
          buzzerOff();
 
          g_mode = MODE_ULTRASONIC;
          g_moveSpeed = ULTRASONIC_INIT_SPEED;
        }
        else
        {
          buzzerOn();
          delay(100);
          buzzerOff();
          digitalWrite(LED_PIN, LOW);
 
          g_mode = MODE_IR;
        }
 
        break;
      default:
        break;
    }
  }
  else
  {
    if (g_mode == MODE_IR)
      Stop();
    else if (millis() % g_stepPeriod == 0)
      doUltrasonicCar();
  }
}
 
void doUltrasonicCar()
{
  int distance = UltrasonicSensor.distanceCm();
  
  boolean isBlocked = (distance > 0 && distance < 60);
  if (isBlocked)
    g_timeLastBlocked = millis();
  else if (millis() - g_timeLastBlocked < 100)
    isBlocked = true;
 
  if (isBlocked)
    digitalWrite(LED_PIN, HIGH);
  else
    digitalWrite(LED_PIN, LOW);
 
  boolean isStuck 
    = (g_numTurnSteps > g_maxTurnSteps
      || g_numStepsForward > g_maxStepsForward);
 
  if (g_ebrake == EBRAKE_STOP && !isBlocked)
  {
    // /unstuck, ready for go signal
    g_ebrake = EBRAKE_WAIT; 
    return;
  }
  else if (g_ebrake == EBRAKE_WAIT && isBlocked)
  {
    // "Go!"
    ResetUltrasonic(EBRAKE_GO);
    return;
  }
  else if (g_ebrake == EBRAKE_GO && isStuck)
  {
    // stuck -- yank ebrake
    g_ebrake = EBRAKE_STOP;
    Stop();
    return;
  }
 
  if (g_ebrake != EBRAKE_GO)
  {
    // halt until !blocked and receive "Go" signal
    return;
  }
  
  if (isBlocked)
  {
    // evasive maneuvers!
    randomSeed(analogRead(A4));
    int randnum = random(300);
 
    if (distance > 30)
    {
      if (randnum > 190 && !g_rightFlag)
        TurnLeft();   
      else
        TurnRight();  
    }
    else
    {
      if (randnum > 190) 
        BackwardAndTurnLeft();
      else 
        BackwardAndTurnRight();
    }
  }
  else
  {
    // ONWARD!
    Forward();
  }
}
 
void ResetUltrasonic(int brakePos)
{
  g_rightFlag = false;
  g_numStepsForward = 0;
  g_numTurnSteps = 0;
  g_ebrake = brakePos;
  
  if (g_debug && g_mode == 0)
    Serial.println("Reset");
}
 
void Stop()
{
  MotorL.stop();
  MotorR.stop();
  
  if (g_debug)
    Serial.println("Stop");
}
 
void Forward()
{
  g_numStepsForward++;
  g_numTurnSteps = 0;
  g_rightFlag = false;
 
  MotorL.run(g_moveSpeed * g_leftTrim);
  MotorR.run(g_moveSpeed * g_rightTrim);
  
  if (g_debug)
    Serial.println("Forward");
}
 
void ForwardAndLeft()
{
  g_numStepsForward++;
  g_numTurnSteps++;
  g_rightFlag = false;
 
  MotorL.run(g_moveSpeed / 2);
  MotorR.run(g_moveSpeed);
  
  if (g_debug)
    Serial.println("Forward+Left");
}
 
void ForwardAndRight()
{
  g_numStepsForward++;
  g_numTurnSteps++;
  g_rightFlag = true;
 
  MotorL.run(g_moveSpeed);
  MotorR.run(g_moveSpeed / 2);
  
  if (g_debug)
    Serial.println("Forward+Right");
}
 
void Backward()
{
  g_rightFlag = false;
  g_numTurnSteps = 0;
  MotorL.run(-g_moveSpeed);
  MotorR.run(-g_moveSpeed);
}
void TurnLeft()
{
  g_rightFlag = false;
  g_numStepsForward = 0;
  g_numTurnSteps++;
 
  MotorL.run(-g_moveSpeed);
  MotorR.run(g_moveSpeed);
  
  if (g_debug)
    Serial.println("Left");
}
void TurnRight()
{
  g_rightFlag = true;
  g_numStepsForward = 0;
  g_numTurnSteps++;
 
  MotorL.run(g_moveSpeed);
  MotorR.run(-g_moveSpeed);
  
  if (g_debug)
    Serial.println("Right");
}
 
void BackwardAndTurnLeft()
{
  g_rightFlag = true;
  g_numStepsForward = 0;
  g_numTurnSteps++;
 
  MotorL.run(-g_moveSpeed/2);
  MotorR.run(-g_moveSpeed);
 
  if (g_debug)
    Serial.println("Backward+Left");
}
void BackwardAndTurnRight()
{
  g_rightFlag = false;
  g_numStepsForward = 0;
  g_numTurnSteps++;
 
  MotorL.run(-g_moveSpeed);
  MotorR.run(-g_moveSpeed/2);
 
  if (g_debug)
    Serial.println("Backward+Right");
}
 
void ChangeSpeed(int spd)
{
  g_moveSpeed = spd;
}

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