I-Are-Bot Ramp

I-Are-Bot needed a ramp so I started working on some prototypes. The idea i got from a forklift, use the weight of the machine to lift. By tilting my servos up an down I can change the angle of the ramp and thereby lift an opponent.
The first two prototypes was discarded as they were too unstable and weak, but the third one turned out pretty well.

The two aluminum profiles attached to the ramp are mounted on the wheel-axis and can be folded. In a angled outright position the ramp touches the side of the gearbox and constrains the ramp to go further down. In a folded state the ramp looks pretty slick, but the ramp prevents the lifting-arm from going up and down. The solution to this was to mount the lifting-arm further up. To do this I’d to build a extra mount, I saw a perfectly good reason to practice my CNC-skills and started CAD:ing.

The ramp can hold much weight, I’ve tried weights around 300g.

The prototypes.

I-Are-Bot’s new PCB

To drive all 6 engines of the same H-bridge is not recommended, it tends to get hot, pretty hot. I was thinking of make a extension card with three H-bridges on it, but then I’d have some weight issues with my bot, it has to weigh less then 500g. The solution was to build a new PCP with htree H-bridges.

Because I never have created a PCB before I was a little bit unsure of how to do it and if I would do any errors. But I’d much help from folks at CRF and it turned out to be a win!

Benjamin at CRF showed me KiCAD which is a great program. It is very user-friendly and you’ll get started quickly. Here’s a great tutorial for KiCAD from CuriousInventor.com.

I drawed the schematics nearly exactly the same as on the Introkit09, but i added two extra H-bridges (L298).

I got a little bit help from Benjamin and Victor to print and make the PCB.

All my resistors and LED’s is surface-mounted so I was a little bit worried that I would have problems while solder. I then watched “Surface Mount Soldering 101″ from CuriousInventor.com and started solder, it turned out to be very easy.

I soldered LED’s with different colors on my PCB, i thought it would be much easier when debuging. I also made up a new ISO for Power-indicators, white LED’s, white! 🙂

I-Are-Bot

I-Are-Bot is a robot I’m currently working on for Robot SM 2010 (http://www.robotsm.se).
A bot has to be 100×100[mm] to enter the competition, mine was about 130, therefore I had to built an unconventional bot 🙂
Two mini-tower 9G is lifting each wheel pair.

CAD

To calculate the arm-lengths and servo-positions I had to draw it all in CAD.

Prototype

The prototype turned out pretty well, and after a little fine-tuning did the wheel pairs going up and down without problems.

Video of the CAD and prototype