Today i finished the board for R1v2. I added two status LEDs to the power lines, one for 5v and one for 3.3v.

Also, i added the header for ICP, a RS232 header, a pair of switches, the header for the sensor board, a uC controlled LED and a hex input switch.

After the hardware was completed, I programmed a quick piece of software to allow me to read the status of the hex switch, and toggle the LED over the RS232 link.

So tomorrow the plan is to get the stepper motors running, using interrupts in the uC.

Due to some last-minute hacking trying to fix rooter’s boards the day before my dissertation demo, and some really really bad connections in between the different boards, I’m now rebuilding and replacing most of the boards. I have decided to keep the regulator board and possibly the sensor board, but everything else on v2 is going on a single piece of stripboard.

This allows me to do away with one of the microcontrollers, and the (very troublesome) connection in between the main board and stepper driver board, and should hopefully leave me with a working mouse!

Here are some WIP pictures from tonight:

I’ll be posting more pictures tomorrow, and a report from the UK MicroMouse Championships at the weekend!

It just occurred to me that i have no pictures of wrecs on here since… well… forever… anyway, here are some recent pictures (about a month old). The only differences between then and now is that he now has a 10.4″ LCD screen on top, which will be activated when there is a person within a couple of meters of him.

The next step in hardware is to design and build the power distribution board, which will supply 12v and 5v to the rest of the electronics.

In software the next step is to get a bluetooth adaptor working, and link in a wiimote :).

I’ve been having some major trouble with my sensors lately on rooter, which has been holding me up for about 2 weeks. This week i decided to spend as much time as possible trying to get them to work, and eventually worked out why v1.0 wasn’t working… The IR LEDs were in the wrong way round! It appears i’d been taken for a fool by the QRD1114 datasheet, and managed to spec up a board where the phototransistors were in correctly, but the LEDs were backwards.

I went back to the breadboard, trying to get the LEDs working as they were meant to, and realised after half an hours testing that I have somehow managed to blow one of the output pins on my AVR, and then chosen that pin to drive the test LED!

After i had worked out that this was the problem, I quickly got an IR LED working, and managed to test it using my digital camera, which can pick up IR!

With this setup, and the output of the phototransistor tied to ground through a 150k resistor, this gives me a reading of between 100 and 350 on the ADC between 90mm and 20mm, which is perfect for micromouse applications.

After getting a working model on the breadboard, i refactored the schematic i had previously designed in eagle, this time hooking up the LEDs correctly, and improving the Resistor & connector placement, which had been interfering with the stepper board connector, as the two boards hang above each other!

I also added a ‘power OK’ LED, which i might switch for a white ultrabright one to give me a headlight!

Here are some pictures of my completed micromouse chassis, along with all the boards.

Everything on the chassis is mounted using velcro, for easy attachment and removal.

There are 4 seperate boards that make up the control circuitry:

• Sensor board, containing 4 IR photoreflectors, which attaches to the main control board.
• The stepper driver board, which uses an ATTiny2313 to sequence 2 step / direction into the correct outputs to drive the motors.
• The Power regulation board, which carries an LM1084 3.3V regulator, to drive the motors, and a LM2940CT 5V low dropout regulator, to drive the electronics.
• The main control board, which contains an ATMega16, and controls all the running of the robot, and controls all the maze searching and running algorithms.

I’ve had this puppy sat in my bits-box for a while now, just waiting for me to do something with it. Tonight I broke out the soldering iron, whipped up a 7.5v regulator circuit for it, and attached a composite lead.

Linked it up to my Powerbook, Et voila! A working 5″ LCD Unit, not bad for 20 Quid!

If the 10″ VGA LCD doesnt work out on wrecs, due to power or other issues, i’ll be using this attached directly to the VGA output of the Epia board.

Got the AVR code for the stepper motor drivers working today, and the Voltage regulation for running from a battery, at this rate, I’ll have the mouse moving by wednesday / thursday

Heres a sneak peek of my uni dissertation, my micromouse robot

Fingers crossed, it’ll be up and running by RoboTIC 06!