So it's been years since I started this project and I'm happy to say it's come a long way. Since the last update I've made several significant changes.
1. The screen. The LCD I had in there was nice but didn't really produce enought light to be usable outdoors. I have replaced it with a 512x512 RGB LED matrix which, while it is much lower resolution, has a far superior light output and more vibrant colors.
2. The chassis. I had originally just stuck a flat piece of steel in the bottom of the case to attach motors to. This proved to be insufficent so I built a box frame underneath out of T-slot aluminium extrusion and bolted that to the steel plate.
3. Treads. The wheels I had been using were great on carpet but even the slightest bump was a major issue. After a brief experiment with omni wheels I decided to ditch them entirely and upgrade to treads.
4. Motors. Immediatly after getting the treads it became clear that the gearhead motors I was using didn't have enough cowbell. After some research I settled on a pair of 45 watt 24 volt worm gear motors. This presented some challenges and I ended up having to cut two large holes in the bottom of the case to accomodate them. It was all worth it however because now Steve the Robot has an excessive amount which, coupled with the treads, gives it excellent mobility.
Up until now I have always used RC controllers for this guy. While that works well I plan to build a more fitting interface in the near future. I'm going to use a pair of Arduinos with NRF24L01 radios for communication and an old Apple 2e joystick as a controller. Currently I am designing a sort of backpack for the joystick to house one of the Arduinos and a small LiPo battery. Hopefully this should be completed soon.
I started by gutting the entire machine and stripping out all but the essential structural components.
Then I added a steel plate to the bottom for structural integrity. This plate is also acting as a heat sink for my Sabertooth 2x12 dual H bridge motor controller.
I mounted my motors to the bottom and added two little casters on the front and back.
After printing out a picture of a smiley face to put in the screen hole I connected the Sabertooth controller to my Spektrum DX6i and spent some time chasing my cat around and annoying my girlfriend.
The little Mac then spent a couple months sitting up on a shelf in my hobby room, it's printed face grinning patiently down as if it were mocking me; taunting me to take to project further.
At some point I was describing it to a friend and he proposed the idea of putting an LCD or TFT screen on it and using it as a functioning computer, an idea which had actually crossed my mind before I started this project but honestly the idea carried a little too much of the hipster/lumbersexual vibe and the thought of being "that guy" who uses a vintage Mac in an indie coffee shop while listening to show tunes and sipping fair trade coffee brought my piss to a boil.
The Mac robot thing seemed refreshingly impracticable by contrast, plus I had already mounted the wheels and motors and it was quite entertaining to watch it scuttle around my apartment. The idea of having a functioning screen was somewhat attractive though so I purchased an 9" 4:3 TFT panel from eBay and when the 8" 16:9 TFT panel arrived I quickly fashioned a mounting method using MDF particle board and a piece of acrylic to protect the screen. I connected the screen to a Raspberry Pi and the results were quite satisfying. It's actually rather bizare to see high quality videos playing on a Mac from 1991.
This was all well and good but to be honest I really didn't put enough work into it and the wiring was crappy. Also the whole platform wasn't quite stable due to the casters being slightly too small which allowed it to tip forward and back a little too much....