Most don’t seem to know about these guys, but Hitec actually made digital servos that have more sophisticated robotics capability: serial read/write of position and speed, and ability to read current.
HSR-8498HB is the smaller of the two, looks to go for about $60 (unless sparkfun can do it cheaper…) and
HSR-5990TG is the larger, which is a pretty crazy strong servo (33 kg*cm).
You can communicate with them using Arduinos:
http://www.arduino.cc/cgi-bin/yabb2/YaB … 1227720391
and you can write a different ID for each and have them all on the same bus.
The servos themselves are also much easier to mount directly into joints (since there’s a freewheel on the other side), and with a little programming:
http://www.youtube.com/results?search_q … dance&aq=f
So yeah, it looks a little more expensive ($60), but the standard openServo board (not Sparkfun’s) is itself $30, with lots of post-assembly required, and people still seem to have a lot of trouble getting Sparkfun’s board (and presumably the other one) to work properly… setting up your own (especially first) PID is never a good time. Maybe Hitec just doesn’t care to sell it on its own, and you guys can negotiate a better deal?
Cheers
-T