Lynxmotion Tech Support

The Femur appears symmetrical one way but not the other. Notice the protrusion. If you flip the femur end-for-end, symmetry. But if you rotate the femur 180 degs about its long axis, the protrusion points the other way.

An early 1960s USAF accident investigation found a similar part in a landing gear linkage. Installed either way, the gear could be retracted, but installed wrong, and the gear could not be extended for landing. The fix was to redesign the part so that the mounting points were no longer similar and could only be mounted the right way. Murphy's law in that instance was that, "If a part can be installed wrong during maintenance, eventually it will be."

Of course, the A-Pod is unlikely to cost as much as that jet or be as critical to the lives of its pilots.

And I would never suggest that Lynxmotion redesign all the SES parts so they can only be installed one way.

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Ted, RoboTed
Never quite finishing means never having to admit failure!

OK, single axis symmetry! I couldn't see it that well.

Interesting story about the landing gear linkage.

Alan KM6VV

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That's OK; I had to Google the word "femur" so I knew which part to look at.

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Ted, RoboTed
Never quite finishing means never having to admit failure!

That's all part of the learning experience.

its coming along great. thanks for the images guys.

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Jonny Poole,
Freelance Concept Art & Animatronics, 3D Art and 3D Modelling, as well as Physical Modelling, Mechanical design, and illustration.
http://www.innerbreed.co.uk/
Create, Innovate, Inspire.

Things were a little rushed... The Femur was made right, but my verbal assembly instructions to James made it impossible to assemble correctly. That was my fault. Over the short break I have made many changes. I should have everything in house this week to build it up.

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

I prefer to speak in images...

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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

Thanks for the images James!

This guy is turning out pretty nice. The mandible/head rotate is perfect! It's smooth as butta and there is no slop. I've changed the bottom to accept a large lipo if desired. The tail can accept a microcontroller or two of them as the original. The body can accept an SSC-32 to simplify the wiring. The mandible head plate has extra SES holes, but I'm dropping them on the production version. As you can see the legs are assembled using the 45 degree brackets, as the attempt to use our normal coxa design didn't work out. So the femurs are correct now. I will shoot some close up images to show off the features. I also have the tibia assembled with ground contact switches. First test went extremely well. Minor tweaking will make it perfect. Should probably weigh it now as well. I'm stoked!

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

Here are some images of the ground contact foot switch. It's pretty much the same as the other ones in principle. A snap switch with a movable segment in the tibia that actuates the switch.

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

Looking very good Jim!
That's more like it!

I like the options of having the SSC-32 inside the body and the BB2 in the tail. I think its a good idea to concentrate most of the mass in the center of the robot by placing both battery and SSC-32 in the body (if that's possible?).

The proportions looks fine. I would recommend using 5645's servos in the mandibles if you wan't an even better grip, 645 will do the job though. But there is a significant difference in using digital vs analog servos when it comes to holding torque.

Looking forward to more pics!

EDIT:
Wow! You beat me to it.
The contact switch tibias looks awesome! Wan't one... (six)!
I bet it will work very fine.

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[b]Kåre Halvorsen, Zenta[/b]
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Zenta's blog
http://zentasrobots.com/
Zenta's YouTube channel
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Thanks a lot Kåre! It really means a lot to hear that from you! Yeah I hated leaving the upside down femur picture as the latest progress, but just ran out of time. I'm really liking the look of it now.



Yup it is possible. I figured the vertical hip servo was already much lower than the bottom body panel, so I took advantage of it and implemented 3/8" standoffs for the battery cover. It lowers the ground clearance a bit, but even that behemoth 8000mAh battery fits inside the chassis and that's with the SSC-32 lowered 1" inside the top chassis panel.





Not sure if I should make the 5685 (7.4vdc version of the 5645 which is going away) the default or make them an upgrade. We'll see... Here is an image of the mandibles/head rotation. I am extremely pleased with how well this worked out!





A minor tweak to the holes on the movable portion of the tibia and it's perfect.

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

great update. id put this down as being the best kit you guys have pulled out of the bag. i feel it will also come with a large price, but for those who will be able to afford it, then im sure they will be more than happy.

excellent work.
i will be ordering the ground contact legs... will the tibia be available as a lone product or will i have to buy the whole leg?

oh its sexy..

_________________
Jonny Poole,
Freelance Concept Art & Animatronics, 3D Art and 3D Modelling, as well as Physical Modelling, Mechanical design, and illustration.
http://www.innerbreed.co.uk/
Create, Innovate, Inspire.

Okay, Snailkeeper, we are really starting to need that Envy smiley now!

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Ted, RoboTed
Never quite finishing means never having to admit failure!

I rather think you've got a sufficient vocabulary to easily compensate for the lack of a smiley. Just sayin'.

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Beth
Lynxmotion, Inc
http://www.lynxmotion.com

THANKS I COULD HELP BRO

Thanks for the good words Jonny! Kåre deserves all the credit, I'm just making it available...



We will probably sell a full kit of everything, and the basic walker as a kit so you can add on the abdomen and mandibles later. We'll also sell the legs separately, but not sure about breaking the tibia out of the leg. We'll see what we can do.

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

yes i thought this might be the case. its a good idea and a nice way for people to build up a custom robot or save up to get the full kit while getting a chance to play with it before the kit is complete.


if not i might just reverse engineer the design.

_________________
Jonny Poole,
Freelance Concept Art & Animatronics, 3D Art and 3D Modelling, as well as Physical Modelling, Mechanical design, and illustration.
http://www.innerbreed.co.uk/
Create, Innovate, Inspire.