although it is an obvious innovation, i cant help but think how pathetic and helpless it looks.
like a dog with no hind legs.
i almost cried tears of pity for the poor thing.

Posted at 9:13 am on Sep 5th, 2009 by soggy pretzels

although on a purely tech point of view, it is amazing. i have been looking for something like this for a while now. it seems hard to recreate with cheaper parts. am i wrong?

Posted at 9:16 am on Sep 5th, 2009 by soggy pretzels

Soggy Pretzels –> The legs appear to only have 2 actuators on each of them. If more were used in a configuration closer to that of a mammal then it probably would have more stability. Also they could probably be setup with some sort of hardware/software neural network to make it run smoother.

I think it looks like a sea turtle being dragged. Though they typically use their underside as a fifth leg.

Posted at 9:31 am on Sep 5th, 2009 by Drake

I went to a talk the creator (Bill Bigge) did at the BuildBrighton hacker space. Its a research project for his PhD. The idea was to make something the home builder could afford. MIT have something like it but its massively expensive.

Posted at 9:57 am on Sep 5th, 2009 by Mark

@soggy pretzels, I was thinking dog with busted backbone, the robot looks pathetic like it needs to be put down.

Posted at 11:19 am on Sep 5th, 2009 by Scott

awesome, the movement is very interesting.

Posted at 11:44 am on Sep 5th, 2009 by Larry

It looks pretty cool, definitely a very organic feel to the motion.

Has anyone noticed that the graph in the “Programmable Spring Actuators” link is completely useless? What is it plotting??

Posted at 11:55 am on Sep 5th, 2009 by Satiagraha

Very impressive motion. Looks like dog got hit by a train, eh soggy?

Posted at 12:10 pm on Sep 5th, 2009 by Mic

now if only u make it instead of spring like make it were it walks on it own.

Posted at 1:29 pm on Sep 5th, 2009 by monkeyslayer56

I did some research on the locomotion in the cat. The stepping reflex is hardcoded in the neural networks in the spine of all mammals and works a lot like this robot. When one leg has reached its hind position, it is brought in front and the other leg is inhibited from lifting up in order to support the weight. This is a fantastic demonstration of this concept. Google «Central pattern generator»

Posted at 6:36 pm on Sep 5th, 2009 by DrNick

it’s awesome! I’d love to make that into a zombie half-corpse on a noose and drag it around the neighborhood on Halloween!

Posted at 9:40 pm on Sep 5th, 2009 by 24601

I can not help but imagine this with grey rubbery ’seal’ skin as a toy.

Posted at 2:41 am on Sep 6th, 2009 by memals

NightMareish zombie torso!
Why won’t you die?!?!

Posted at 4:10 am on Sep 6th, 2009 by le'chef

I can see this as a awesome trailer for increasing the load of Boston Dynamics Big Dog

Posted at 6:49 am on Sep 6th, 2009 by deedubs

Satiagraha:

The graph is actually the method of defining the spring damping behavior of the actuator – the X axis is the actuators angle (the axis name was clipped from the image) and the Y axis is force (for the red line) and damping (for the other two lines) you ‘draw’ the spring forces and damping forces with the mouse and download the configuration to the actuator, when it runs it reads its angle and looks up the force value for that angle, reads its velocity and adds in the damping, then applies that force to the output.

This lets you define arbitrary spring damping behaviors that vary across all angles. There are two sets of damping, one for each direction of motion, so you can make things that are highly damped but only in one direction, and only across certain angles.

Posted at 6:05 am on Sep 7th, 2009 by Bill Bigge

General note – my prototype actuators are really weak and I could only afford to make four, hence the reason for two legs with two degrees of freedom – you can see in the video that I put a counterweight on the back of the bot to help with the weight. This isn’t a major issue, I just need better motors. The actuators are a bit over-sized as well but I should be able to engineer them to fit into something about the same size and power (and price) of some of the robot servos that are on the market.

You could easily extend this robot to create a hexapod with three degrees of freedom per leg – it would still walk when you pulled it, and you can extend the control system further so it could walk autonomously – I’m also working on embedding a small neural network in each actuator to reproduce some more biological CPG based behaviors.

And also, yes – with the addition of a balance sensor you could use them to make your own miniature version of big dog, but for a few hundred dollars.

Posted at 6:21 am on Sep 7th, 2009 by Bill Bigge

kill it with fire!

Posted at 10:01 am on Sep 7th, 2009 by ihavenobeer