Lynxmotion Tech Support

Hi All,

It looks like porting the forum to the new version messed up my First post in this topic. I can't believe that I only posted one line… Ah well who cares, I've got some better news.

I've been working hard on this fella for the last 2 weeks. And with result! Yesterday the hybrid walked over the "Theory of applied Robotics kinematics, dynamics and control" by Reza N.Jazar. (Hardcover 695 pages). Robot beats Robot book!

I'll try to post a vid soon.

Xan

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[b]Share, Use and Improve![/b]
Digging trough: [i]Theory of Applied Robotics: Kinematics, Dynamics, and Control[/i]
Xan's YouTube Channel
http://www.youtube.com/xanore

really Cool

I would like to see how this looks. I hope you make a movie

greez t4ndu

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build your dream!

Wow! That sound awesome! Congratz Xan!
I'm really looking forward to see a vid of that.

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[b]Kåre Halvorsen, Zenta[/b]
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Zenta's blog
http://zentasrobots.com/
Zenta's YouTube channel
http://www.youtube.com/ZentaOlbaid
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Hi Guys,

As promised a video of the hybrid walking over an obstacle. Remember, this is just the first time it actually walks over an object so there is still a lot of improvement to do. Enjoy



Xan

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[b]Share, Use and Improve![/b]
Digging trough: [i]Theory of Applied Robotics: Kinematics, Dynamics, and Control[/i]
Xan's YouTube Channel
http://www.youtube.com/xanore

Hi Xan,

It is great to see the progress here. Looks like it is detecting the object very well

Congrats!
Kurt

Thanks for sharing Xan!

This is awesome progress! Did you try the TA part combined with other gait too? Cool to see you V2.0 in action

_________________
[b]Kåre Halvorsen, Zenta[/b]
-----------------------------------------
Zenta's blog
http://zentasrobots.com/
Zenta's YouTube channel
http://www.youtube.com/ZentaOlbaid
-----------------------------------------

Thanks for the positive reactions guys!

I've tried to upload a demonstration video about the new features in 2.0. The video was cut off because off maintenance at YouTube. :s I'll try to Upload it again when I get home today.

Xan

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[b]Share, Use and Improve![/b]
Digging trough: [i]Theory of Applied Robotics: Kinematics, Dynamics, and Control[/i]
Xan's YouTube Channel
http://www.youtube.com/xanore

Very cool Xan!

The video looks a tad strange though... Did you increase the speed or something?

_________________
Curiously enough, the only thing that went through the mind
of the bowl of petunias as it fell was "Oh no, not again."

James "Don't call me Jim" Frye
Lynxmotion, Inc
http://www.lynxmotion.com

Nope, the video is 1x speed! It is a bit wobbly once the balance mode is on. One of the things I need to figure out.

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[b]Share, Use and Improve![/b]
Digging trough: [i]Theory of Applied Robotics: Kinematics, Dynamics, and Control[/i]
Xan's YouTube Channel
http://www.youtube.com/xanore

I notice the body shifts a little bit while taking steps. Are all six legs sensing the ground? Would it be possible to turn sensing on or off depending on which leg is in the air? toggling the input would allow you to only read the one leg that is in the air. Once a leg makes contact, you can switch reading the input on the next lifted leg and so on...

It looks like it might be reacting to input from all six legs? I don't know, perhaps I can spark some new ideas.

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Mike

The robotics nut.

Ah, ok. I was wondering what that was. I'll let you get to the figuring out part.

_________________
Curiously enough, the only thing that went through the mind
of the bowl of petunias as it fell was "Oh no, not again."

James "Don't call me Jim" Frye
Lynxmotion, Inc
http://www.lynxmotion.com

Wait, first, lets watch it again in slow motion. There was a lot going on in that video and we don't want to miss anything! ...

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Mike

The robotics nut.

Been staring at this thing for a while now. It looks like the leg positions are continuously updated even when the single leg is being lowered. Why can't you leave them all as-is while you lower one leg, then adjust them all when the lowering leg makes contact? This has to be faster.

It's easy for me to comment, because making a comment does not require any knowledge at all. lol

If you make some assumptions...

Robot body will try to remain flat.
Object to be walked over is not taller than the lifted leg minus some (working value)
Object to be walked over will also be flat.

Then a simpler mode could prove to be faster but still work reliably. I know you really want it to not have these restrictions.

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Jim Frye, the Robot Guy
http://www.lynxmotion.com
I've always tried to do my best...

Thats exactly what I was saying a few post up there ------^

Only read the leg that is off the ground and leave the rest of the legs fixed, but you have a good idea about doing a quick query of all six legs before taking the next step. But like you said, I'm just throwing stuff across the table blindfolded.

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Mike

The robotics nut.

Hi again Xan,

As I mentioned it looks great. My guess is that you are doing this by breaking up the move into really really small moves and then testing the input to see if you hit before you try moving the next little bit. Out of curiosity have you tried the other approach, which was to try bigger moves and continusously checking to see if you get contact and then abort the move and then ask the SSC-32 where it thinks it is. If so how was the speed and how far off did it appear to be. My guess is that you could make a reasonably good guesses. That is if you told the leg to move from point A to Point B in time X and you hit something at time Y, you may be able to reasonably compute where the leg is at the point in time even without asking the SSC-32. Just a thought.

Maybe I should have ordered some more FSRs with my current order ...

Kurt