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Hexapod V5 Foot design

PostPosted: Thu Jun 05, 2008 3:09 pm
by Matt Denton
I've had a few people ask for more details on the V5 foot design, so here they are.

The foot is attached to the tibia via an 8mm ball (A) which locates into the upper foot socket (B). This upper foot socket is then attached to the lower foot plate (C) via two ball joints to form a hinge between (B) & (C). There is a PCB (D) mounted to the top of (B) which has a micro switch (E) soldered onto it. There is also a retaining plate (F) screwed to the top of (B) to hold (A) in place. At the front of (B), there is a M3 grub screw which pre-tensions the micro switch and stops the hinge between (B) & (C) from opening too far. The spring between (F) and the tibia base re-aligns the foot when it is not in contact with the ground.

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ISO view
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Front View
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Re: Hexapod V5 Foot design

PostPosted: Fri Jun 06, 2008 1:48 pm
by Tony
thanks, detail enough for new learner. is it possible to use other solution for ground senser as it looks so big on hexapod V5.

Re: Hexapod V5 Foot design

PostPosted: Fri Jun 06, 2008 4:47 pm
by Matt Denton
Tony wrote:thanks, detail enough for new learner. is it possible to use other solution for ground senser as it looks so big on hexapod V5.


Yes it can be much smaller, but I wanted a large surface area to dissipate weight on soft ground. This was a proof of concept design for something much bigger!

Re: Hexapod V5 Foot design

PostPosted: Thu Jun 12, 2008 5:02 pm
by circuit
Hello Matt,
I am very interested in foot sensors used in your Hexapod v4. How does that work? What sensors have you used and where are they placed?

I love your work, keep it going!

Re: Hexapod V5 Foot design

PostPosted: Thu Jun 12, 2008 8:22 pm
by Matt Denton
circuit wrote:Hello Matt,
I am very interested in foot sensors used in your Hexapod v4. How does that work? What sensors have you used and where are they placed?

I love your work, keep it going!


Hi, Welcome to the forum!

The V4 design used pressure sensors located half way down the tibia. These sensors were mounted in such a manner that they would decrease pressure on the sensor when pressure was applied to the foot. Although pressure sensors were used, I only used them in a binary fashion,eg ON/OFF, no pressure information was needed for my terrain adaptation engine. There is no complience in the legs, just ground contact sensors.

In V5 the ground contact sensor is a simple micro switch as can be seen above.

Re: Hexapod V5 Foot design

PostPosted: Wed Jan 06, 2010 11:29 am
by innerbreed
thank you matt. the detail is great. 8-)

Re: Hexapod V5 Foot design

PostPosted: Wed Jan 06, 2010 10:14 pm
by innerbreed
You definitely put thought into the design of this. Compliant in three dimensions, switch contacts orientated in a triangle. I might explore that idea and see what i can fashion.
a very smart way to make sure there is contact on every step.
What's the approximate width/length of this foot?

again great work

Re: Hexapod V5 Foot design

PostPosted: Mon Jan 11, 2010 9:09 am
by Matt Denton
Hi,

The foot is 60mm across the tip of the triangle, the ball joint used is an 8mm IGUS ball.

Cheers :)

Re: Hexapod V5 Foot design

PostPosted: Wed Apr 14, 2010 6:05 am
by Aggrav8d
Would a rubber foot glued to a push button do the trick?

Re: Hexapod V5 Foot design

PostPosted: Fri Apr 30, 2010 1:52 pm
by jycegrcia
Great Hexapod V5 design. You have given great information about this foot , specially for beginners like us. I would definitely like to make such foot design in my free time.