September 20, 2013
Today I received two Tiva Launchpad development boards from Texas Instruments. TI had a $25 sale coupon that I used, so I only spent $0.98 for them.
These are the successor to the Stellaris Launchpad boards that I was going to use. TI revamped the product names and put a more capable chip on the board. This chip now ha s16 channels of REAL PWM control as well as Quadrature Encoder processing hardware. I will upgrade the motor controller board to this even though an Arm Cortex M4 is really overkill. It has 256Kb Flash, 32k Static ram, 2k EEPROM, 16 PWM outputs and runs at 80Mhz!
I also found really interesting link to a supplier: http://www.superdroidrobots.com/shop/ has a lot of really interesting and sometimes hard to find stuff. It looks like I will get my motor drive sprockets and chain there.
Let us not forget the Mad Scientist Hut http://madscientisthut.com/ in Lyons, Colorado. Good stuff here. I especially like the Magnetic Rotation Encoder, no optical involved. I hope they are OK with the flooding.
September 16, 2013
I have moved my web page/blog over to WordPress. The previous link will still work.
I have spent lots of time working on my Bot. He/she now has a partial body and made his first test runs across the floor.
However I have found out a few things that have caused me to stop work and do a major rebuild of the drive system.
This weekend I was a volunteer at Portland, Oregon Mini-Maker Fair. I had a change to observe several robots such as Asto-Mechs (R2-D2 type), Lego, Combat Bots and Loki.
I have a long talk with David Shinsel creator of Loki. (See: http://www.dshinsel.com/). Dave and I actually work at the same Intel site and it turned out that our thought processes in a bot are the same. What I was doing was almost exactly what Dave had done with Loki. I just am using more local controllers.
One thing I saw was that no one was using direct drive of the locomotion motors. Since I have been having headaches with my system I have decided to rebuild the base.
The base will now be a framework instead of a solid pan. Each motor will drive and axle via a toothed timing belt. This will isolate the motors and wheels from any vibration an jerking. It also will allow flexibility in mounting the motors.
I probably will have a prototype by the end of the month. First I have to get the parts!