See Updated Walking Engine Page
Because the Hi-Tec HSR-5995TG "Robot Servos" have different travel and signal characteristics than "standard" servos, the GaitPIC chip won't work, and the Nomad_Walking_Demo.bsp program will need some "adjustments".
The servos are "interesting". I started by checking out the spec sheets on the Hi-Tec sight, and found that the "normal" servos are listed at +/- 40 to 45 degrees, and the "robot" servos at +/- 90. This means that they should move twice as far for a given offset from center.
I also found that they (the robot servos) don't travel with the full range of pulse widths. less that 550 or greater than 950, and you don't get any extra movement. This may be able to be adjusted with the servo programmer from Hi-Tec, and I may be ordering one soon. Besides throwing some things off, this also makes the movement "coarser". If I can get the full range of pulses to be effective, I should have more refined control of the servos.
I got the walking code basically working by doing the following:
*In the data sections, for any of the Words with an offset from center, I cut the values in half.
* I currently have "Raise" defined as 900 and "Lower" at 550.
I may have a little mechanical tuning to do.
I also have to move the pivot, at least for use with the servo wall wart. I had assembled the 'bot with the legs at the innermost pivot, looking for maximum leg lift. If the legs are "under" the robot well, this works OK, but if things get even a little "splayed", then there just isn't quite enough "oompf" and the robot sags. I'm hoping this might be better once I move to a LiPo battery pack. For now, I'll just move the pivot out, probably to the third hole for now. Before I move it, I'll probably put a volt meter in place, and see if I'm getting a voltage drop, or if the voltage is fine, I'll know that hole number one is just too much, at least at 6.0 V. The robot servos are rated at 7.4, and that's where we're headed. That may also make a difference.
At any rate, with the above changes to the walking code, we were moving across the floor. Probably still have some tweaking, but we have a viable starting point!
Once I have things working decent, I'll have more details and also provide the final code.
[To Do: Add notes on final changes, and include link to, and/or display, final code.]