How to make a self controled car with Arduino

Projects General Guidance
1

Hi,
We're actually trying to think about building a self controled car, or at least a car which can avoid obstacles. So we thought about Arduino to program it. Like it's for an exam, we need to have a great thing, making the jury astonished. So we thougt about the robot:
Protocole:
The robot touch an obstacle at right. He goes back, turns left and continue a few centimeters. Then, he turn right to go back to his first objective.
The robot will have 4 wheels, 4 motors, 2 buttons to know where it touchs, an Arduino Uno, a battery and two leds for go back or not.

So is it feasable ?
Do you have special recommandation ?
What exactly do we need ?
Is a motor control shield needed ?

Thx for your answer
The Hunt33r

2

Hi,

Keep it simple. Look at the ardbot: http://www.robotoid.com/servomag/

Some suitable switches are like these: http://arduino-direct.com/sunshop/index.php?l=product_detail&p=203

You might later use distance sensors like these: http://arduino-direct.com/sunshop/index.php?l=product_detail&p=182

DISCLAIMER: Mentioned stuff from my own shop...

3

Maybe a couple of ideas here http://arduino.cc/forum/index.php/topic,8756.0.html
Also, I recommend looking at "makey". a simple robot with car-type mobility.

4

OK thanks for all.
I think we'll take this cart :
1 x YourDuino-UNO 328 (Open Source Copy of Arduino UNO)(Free Cable)
1 x L298N motor drive Shield
1 x 4 - AA Battery Holder
3 x Ultrasonic Distance Measuring Module HC-SR04
1 x LED Assortment 5 colors 10 ea
4 x 5V Stepper Motor

But will batteries be enough for 4 motors, the Arduino, the Ultrasonic Module and leds ?

Thanks for ur answer

5

But will batteries be enough for 4 motors, the Arduino, the Ultrasonic Module and leds ?

The Arduino, ultrasonic module, and leds, yes.

The motors (stepper motors are NOT a good choice for the locomotion, by the way), no way. Not by a long shot. They won't even budge a stepper motor.

6

thehunt33r , I'm not comfortable with what "looks like business" here on the arduino forums. Please ask the questions in a general way or ask me or through the site contact form.

I think the stepper motors you are talking about may be the small ones like this:
http://arduino-direct.com/sunshop/index.php?l=product_detail&p=126

...and if you use the driver boards for these you don't need the L298 board (which would be OK for two DC motors like: DC Gear Reducer Motor 6V 30RPM - emartee.com )

These small stepper motors have a gear reduction and decent torque at 5v but they're not Real fast... I have NOT personally used them on a robot.

Also, think about why you want 4 wheel drive, and how it will steer. You can "skid-steer" on a flat surface, but not too good for carpet..

7

So which motor to use ?
Will servos be enough ? Or is there some cheaper motor to move the robot ?

8

dc motors???

9

So which motor to use ?
Will servos be enough ? Or is there some cheaper motor to move the robot ?

Why don't you tell us the dimensions of the vehicle, so we don't waste time guessing?

10

So... it may be like 30cm long and 15-20 large. or 16:9 ratio :slight_smile:

11

..and built from cast iron, or carbon fibre?

12

think from Meccano. So aluminium :relaxed:

13

Another approach uses "continuous rotation" servo motors that operate on 5V to 6V and are easily controlled by one Arduino pin.
These are called "Robot Servos" by the manufacturer I use.
Examples: http://goo.gl/in6v7

And some like this one are pretty strong: http://arduino-direct.com/sunshop/index.php?l=product_detail&p=131
7 or 8 Kgcm of torque will move a pretty good sized robot..

You would want to run a direct connection from your battery to whatever motors you use.. not from Arduino.

A lot of good robots use two drive wheels and a caster instead of 4 wheels. Some have a body that looks like a car but they are a lot more maneuverable.