Project:Line-following Robot

From Nottinghack Wiki
(Redirected from Line-following Robot)
Jump to: navigation, search

As part of the Arduino 102 (or is it 201?) we built line-following robots...

((insert video here!))

Original photos at https://plus.google.com/photos/101627167067307203883/albums/5758095721560984897 ((upload process takes too long from the wiki so this is in progress))

I want to now move the circuit off my Arduino Uno with breadboard and onto a Xino with a "micro-shield". What's a micro-shield? It's a ghetto Arduino shield that uses just a few of the pins and can be knocked together cheaply with a few scraps of stripboard and pins.

A micro-shield base

I found this tiny bit of spripboard that was 12x4 holes but nicely separated down the middle...

A micro-shield base

I have loads of male header pins (we have boxes of them at Hackspace and I also get them from work) and here I'm using 7 pins that fit in digital pins 8, 9, 10, 11, 12, 13, and the ground pin. That gives me access to 3 digital pins with PWM and 3 without.

The line-follower robot requires two PWM pins to drive the motors via a mosfet. Here's a little circuit diagram I jotted down to help me with wiring...

A micro-shield base

I mounted the two mosfets with drain pins to a common ground linked to the GND pin...

A micro-shield base

I don't want to solder my motor wires on as I want to swap them between projects so I have two header pins per motor connection, slightly bent outwards, one pin goes to source on the mosfet and one pin goes to +5v...

A micro-shield base

I'm using jumpers as little F-F connectors (a little trick I developed to save on expensive female headers - I have hundreds of jumpers knocking around)...

A micro-shield base

The mosfets need gate connections (middle pin) to the PWM pins to switch on the motors...

A micro-shield base

We also have a little jumper wire (in red) to go to the 5v pin on the other side of the Arduino and 5v supplies to the other end of each motor...

A micro-shield base

Now, we also need a header for the Light Dependent Resistor (LDR), an LED to normalise any ambient light, and a calibration pushbutton...

((TODO: LDR, LED, and pushbutton mounts. Software. Mounting on the Xino. New robot design. LDR/LED nose structure.))