Comments on: Obstacle avoidance Arduino robot – build your own larryBot

By: ashraf

ashraf — Thu, 10 May 2012 21:29:35 +0000

i’m having same problem with. did you manage to solve this?

By: lee

lee — Mon, 07 May 2012 17:57:29 +0000

hye larry,below is my code for coding obstacle avoidance robot. i use 2 type of sensor which is Ping sensor and IR Sharp sensor..my problem is when i running the robot its look like my both of sensor is not functioning. Can you detect my problem..i also use L293D motor driver chip..

int i;
int dist1;
int dist2;
int pingPin= 7;
int redpin=0;

int motor1Pin1=4;
int motor1Pin2=3;
int enable1Pin=9;
int motor2Pin1=5;
int motor2Pin2=6;
int enable2Pin=10;
int duration;

void setup () {
pinMode(motor1Pin1, OUTPUT);
pinMode(motor1Pin2, OUTPUT);
pinMode(enable1Pin, OUTPUT);
pinMode(motor2Pin1, OUTPUT);
pinMode(motor2Pin2, OUTPUT);
pinMode(enable2Pin, OUTPUT);

digitalWrite (enable1Pin, HIGH);
digitalWrite (enable2Pin, HIGH);

pinMode(redpin, OUTPUT);

}

void loop() {
pinMode(pingPin, OUTPUT);
digitalWrite (pingPin, LOW);
delayMicroseconds(2);
digitalWrite (pingPin, HIGH);
delayMicroseconds(5);
digitalWrite (pingPin, LOW);

pinMode(pingPin, INPUT);
duration=pulseIn(pingPin, HIGH);
dist1=duration/74/2;

i= analogRead(redpin);
dist2=(6762/(i-9))-4;

if (dist2 > 10 || dist1 10 || dist1 > 5 ){
backward();
turn();

}
if (dist2 5 ){
backward();
turn();
}

if (dist2 < 10 || dist1 < 5 ){
backward();
turn();
}
}

void forward() {
digitalWrite (motor1Pin1, LOW);
digitalWrite (motor1Pin2, HIGH);
digitalWrite (motor2Pin1, LOW);
digitalWrite (motor2Pin2, HIGH);
return;
}

void backward(){
digitalWrite (motor1Pin1, HIGH);
digitalWrite (motor1Pin2, LOW);
digitalWrite (motor2Pin1, HIGH);
digitalWrite (motor2Pin2, LOW);
return;
}

void turn(){
digitalWrite (motor1Pin1, HIGH);
digitalWrite (motor1Pin2, LOW);
digitalWrite (motor2Pin1, LOW);
digitalWrite (motor2Pin2, HIGH);
return;
}

By: JD

JD — Sun, 04 Mar 2012 00:47:11 +0000

i have 4 motors. 4 wheels. so can a single 6 volts battery can power up the motor? I will use two L293D . the stall current each motor is 470 mA.

By: John Doe

John Doe — Wed, 22 Feb 2012 14:34:46 +0000

Do you have any sketch available of your robot, of the cabling using for example fritzing?

By: Shahin

Shahin — Fri, 17 Feb 2012 21:40:05 +0000

Hello there, first of all, thank you for the information/tutorial! I’ve bought the tamiya twin gear motor and tamiya tracks, 2x sn754410ne.

I only use one sn754410ne.

So my setup is
- new 9v battery
- T-twin gear with original motors
- Arduino

When I power it up, it runs for about 20 seconds and then it slows down. When I power it off and then on it does not even move anymore. When I run the motor, it is in the air, so no pull/push power of the ground.
Can I use a bigger battery pack? for example 7 times 9V battery or one LIPO RC car pack?

And are the capacitors necessary? And what about if I use a bigger battery?
Could you please provide me with a link to the right capacitors? Because I could not find the right one on the internet…

Thank you in advance!

By: Godwin

Godwin — Tue, 14 Feb 2012 21:00:03 +0000

What kind of sensor need to measure the speed of a car. I have LV-max sonar -EZO and Arduino uno?

By: larry

larry — Tue, 07 Feb 2012 14:19:44 +0000

I would use a different h bridge chip entirely, voltage seems to be ok for most but it’s the current that’s the issue. Too much current will burn the chip out and stall the motors.

By: larry

larry — Tue, 07 Feb 2012 14:18:54 +0000

for 58, I measured the time the signal took over a set distance.

In terms of the averages, it’s probably the wrong way of doing it e.g. taking multiple readings and then an average. What I should have done is remove any values that are outside of a threshold.

By: larry

larry — Sun, 05 Feb 2012 14:04:37 +0000

You may want to actually improve this or make the project your own rather than just copying it wholesale.

I really should start to leave more bugs in the code to make you think about it before just copying it all

By: bernard

bernard — Sun, 05 Feb 2012 12:02:54 +0000

great! i’m going to use this as my project. thanks a lot