Realtime Rocky

     A couple of updates this week. First, we finally have a running control PC. We received all the parts for our PCIe/104 stack and it all seems to running smoothly. We have a CPU from ADL and IO boards from RTD. Currently we're running Ubuntu 12.04 with Linux kernel 3.8.13 patched with RTAI 4.0 and running ROS Hydro, providing us with beautiful realtime functionality. I'm in the process of modifying the RTD drivers to work with our kernel (they haven't been updated since kernel 2.6, ~2008) so hopefully we'll be reading realtime torque data in the next few days.

     Second, the drivetrains are finally complete. I don't have motors yet, but when I get them I just plug them in via timing belt. We only have one ball wheel at this point, because the aluminum cores are currently on backorder, but we'll have all the wheels in place a few days after those get here.

The first wheel is in and it's working great. We have excellent grip between the drive wheels and the ball wheel and the drivetrains are working beautifully. Near-zero backlash, minimal friction. Each wheel is held in place by (currently) six points, two drive wheels above, two passive rollers above, and two passive rollers below. We might add in an additional lower roller if we have problems with the balls popping out during operation. We do not expect this to be a significant problem.