Let’s crawl


It was hard to derive linear motion out of a motor whose direction of rotation alternates. Initially I tried to design shoes out of erasers but it turns out the friction was too much for it to begin moving. The video for this attempt can be found here – https://goo.gl/photos/QXmh7DSLDyzkFmXM8


To fix this problem, I tried removing the feet and reworked the placement of wires. I got something which moves a little but only on a rough surface like that of a carpet or a rug – https://goo.gl/photos/5Jiy4hLLPD3BEsbm6



Arduino Board
Bread board
Servo motor


 * Servo with Potentiometer control
 * Theory and Practice of Tangible User Interfaces
 * October 11 2007

int servoPin = 7;      // Control pin for servo motor
int potPin   = 0;      // select the input pin for the potentiometer

int pulseWidth = 0;    // Amount to pulse the servo
long lastPulse = 0;    // the time in millisecs of the last pulse
int refreshTime = 20;  // the time in millisecs needed in between pulses
int val;               // variable used to store data from potentiometer

int minPulse = 500;   // minimum pulse width

void setup() {
  pinMode(servoPin, OUTPUT);  // Set servo pin as an output pin
  pulseWidth = minPulse;      // Set the motor position to the minimum
  Serial.begin(9600);         // connect to the serial port
  Serial.println("servo_serial_better ready");

void loop() {
  val = analogRead(potPin);    // read the value from the sensor, between 0 - 1024
  if (val > 0 && val <= 999 ) {
    pulseWidth = val*2 + minPulse;  // convert angle to microseconds
    Serial.print("moving servo to ");
  updateServo();   // update servo position

// called every loop(). 
void updateServo() {
  // pulse the servo again if the refresh time (20 ms) has passed:
  if (millis() - lastPulse >= refreshTime) {
    digitalWrite(servoPin, HIGH);   // Turn the motor on
    delayMicroseconds(pulseWidth);  // Length of the pulse sets the motor position
    digitalWrite(servoPin, LOW);    // Turn the motor off
    lastPulse = millis();           // save the time of the last pulse

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