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DiverBob wrote: »
It's been a hectic 3 weeks with an unexpected trip to Florida for a family emergency and only returning a couple of days ago. Not too much has been happening on the gait generation software. I did get some time yesterday to do some coding and testing where I had the test leg moving from one location to another in a relatively straight line using the IK engine to develop the endpoints for the leg tip. The tip ran fairly straight for about 9 inches and then makes a 1-2 inch swing at the end of movement. I suspect there might be some calibration issues involved, will devise some test to verify.
Later today I want to work some more to refine the software and test out some other ideas. I want the leg to have a smooth stepping motion without any stopping when a leg tip touches down and another leg tip lifts up. It should be a smooth action without any jerking so the tip should start to move in the direction of travel just before it touches down so there is a smooth transition.
I hope to spend some time on the programming during the holidays since we aren't going anywhere this year, would be nice to figure this out before the start of a new year.
RobotBargains wrote: »
To say this is a very neat project is an understatement. I just joined the forum and saw this post and quite enjoyed reading about this what you're constructing, wiring, and programming. The youtube link didn't work for me... url not found. I'm definitely looking forward to seeing more of this project
Publison wrote: »
Thanks for the update Bob! It has been a while, but we were going through the holidays, that's to be expected.
Good news is you are still plodding on.
DiverBob wrote: »
Had some success with the gait engine and am able to get a single leg to cycle through the motions now. Was only getting the leg to move in one direction but finally got the code right to get a full swing of the leg around the coxa pivot point.
I am getting some excessive movement out of the tibia motor where it is not moving smoothly and appears to be 'hunting' around the requested set point. I need to look into that issue now. I did pick up a neat capacitive angular encoder that is good to the 0.01 degrees of motion, I may have to try it out and see if that might help out. I think the amount of tibia movement is very small as compared to the coxa and femur so noise in the precision potentiometer might be giving too many false position readings which then has a larger impact on the small movements needed. Figuring out how to mount the encoder could be a fun trick since I didn't design this into the leg mechanics. I don't want to make a bunch of mechanical changes for something like this, I may put together something simple to check out the encoder concept and see how well it works.