Morbo
Morbo
by koko76
Sat Feb 24, 2007 6:17 am
Hi all, I'm new to this forum, but I've been building robots for a little while now. While this project is not meant to be a complete Robo-1 robot, I figured it might be of some interest to some people here.
http://www.geocities.com/kokop76/morbo/morbo1.html
is a link to the progress report page I've put up. Enjoy!
http://www.geocities.com/kokop76/morbo/morbo1.html
is a link to the progress report page I've put up. Enjoy!
by koko76
Sat Feb 24, 2007 7:00 pm
With any luck I will get more done on this project this weekend. My biggest problem at the moment is that I have to "share" the Haas (3 Axis CNC for those not familiar) at work with actual work stuff. At the moment I'm trying to finish a couple projects, sadly not related to robotics.
by koko76
Fri Mar 09, 2007 5:56 am
http://youtube.com/watch?v=bEeJUXoWNuQ Should make a little more sense of how the leg design works.
by DerekZahn
Fri Mar 09, 2007 4:29 pm
Wow, that's a really nifty ankle joint Eric! I tried a similar concept in the first long-ago version of Bing
http://happyrobots.com/bing/dec10_bing_lg.jpg
but I didn't do a very good job of it. Looks like you got it perfect!
http://happyrobots.com/bing/dec10_bing_lg.jpg
but I didn't do a very good job of it. Looks like you got it perfect!
by JonHylands
Fri Mar 09, 2007 9:16 pm
If you read the master's thesis of the guy who built M2:
http://www.ai.mit.edu/projects/leglab/robots/m2/docs/paluska-masters-m2.pdf
the design of the foot actuators is almost identical.
The interesting thing he did with M2 is to rotate the whole actuator assembly from where you have it 135 degrees, so it is centered behind the "shin/heel".
Regardless of the orientation of the foot to the foot actuators, as long as the actuators are 90 degrees apart from each other, you can get the same level of flexibility in the foot.
The important benefit that M2's design has, is for the "typical" scenario, where the heel is flexing about an axis that is side-to-side (pitch), you get the strength and power of both actuators working together instead of just one.
If this isn't clear, let me know, and I'll post a few pictures...
- Jon
http://www.ai.mit.edu/projects/leglab/robots/m2/docs/paluska-masters-m2.pdf
the design of the foot actuators is almost identical.
The interesting thing he did with M2 is to rotate the whole actuator assembly from where you have it 135 degrees, so it is centered behind the "shin/heel".
Regardless of the orientation of the foot to the foot actuators, as long as the actuators are 90 degrees apart from each other, you can get the same level of flexibility in the foot.
The important benefit that M2's design has, is for the "typical" scenario, where the heel is flexing about an axis that is side-to-side (pitch), you get the strength and power of both actuators working together instead of just one.
If this isn't clear, let me know, and I'll post a few pictures...
- Jon
by koko76
Sat Mar 10, 2007 12:24 am
Totally clear, and it's an avenue I considered (135 deg, or 45 deg would work the same here). It's a good idea, but at the moment I have a couple more things I need to get working before I start messing with that. I'd like to tweak a couple of key things to make the whole thing lighter and more compact, but as a proof of concept what I've got should work nicely. There's always Morbo 3.
To Robo1, how strong is the servo or how strong is the metal? The servos are currently 475HB's which aren't super, but will work for now, especially in a 3DOF leg. The metal won't be bending or even flexing notably any time soon, all sections are .125" thick, so there's no forces here that will affect it.
To Robo1, how strong is the servo or how strong is the metal? The servos are currently 475HB's which aren't super, but will work for now, especially in a 3DOF leg. The metal won't be bending or even flexing notably any time soon, all sections are .125" thick, so there's no forces here that will affect it.