Giger’s upgrades got finalized late Sunday night and I had a bit of time to sit down and start to work on the walking gaits (from scratch). The EX-106+ is roughly 4x more precise than all previous Dynamixels, so the positional values do not translate over well when upgrading from a previous model. What does that mean? It was far simpler to just start over rather than try to scale the values step by step. All new custom brackets used in the legs and feet, as well as new elbow/shoulder brackets and arm extensions. Brackets were designed in Autodesk Inventor 2008 and machined by Rapid Sheet Metal. It’s worth mentioning that all of the custom, as well as the stock, brackets and frames that are used in Giger’s arms and legs are available in our store on our Dynamixel Servo & Bracket page! Even his ankles/hip joints or his entire legs!

A lot of projects tend to only show updates after many dozens and/or hundreds of hours of progress, but I like to show the little steps as I feel it gives one a better view of the evolution of a project and what goes into making a robot work. Keep in mind; I have this gait tuned to a very slow rate so that I can work on the balance and COG shifting correctly, it can then be sped up to a more realistic, useful speed. Here’s a short video of my initial walking gait progress (about 2 hours of programming work so far) on Giger 2.0:

BTW- If anyone is looking for a solid place to get some sheet metal cut/bent or some parts machined, check out Rapid Sheet Metal and their sister company Rapid Machining. I’ll give a bit more in-depth review of them in the followup post where we’ll talk more about Giger 2.0, but I was absolutely blown away by their quality and customer service, so I’ll say it here as well. Check em out! Tell em we sent ya! =)

In Jon’s new Project Thread, he says:

I went out and bought a 1/5 scale RC rock crawler chassis. Just for scale, those tires are 8″ in diameter, and the whole thing is 30″ long. We chose this chassis because it would have no issues going long distances at speed, and it would be able to handle curbs and grass and such with no issues. Being a rock crawler, it also goes slow enough that the sensors can keep up…

Right now, it has the quad core mini-itx mounted, and is being driven around with my Logitech wireless joystick. The motor driver (a Sabertooth 2×25) is controlled from one of my Bioloid I/O boards, which is connected to the bus. A program (written in Squeak Smalltalk) takes the joystick input, and sends speed and steering commands over the bus to the I/O board and the steering servos (AX-12’s).

Here is a short video of it under remote control:

Edit: Another Video just posted!

Inverse Kinematics can be a scary thing to the robot hobby novice. There is a lot of trig involved, and if you’ve learned anything from reading this blog you’ll know that being Norwegian apparently makes it a lot easier to grasp.

Mike Ferguson of Vanadium Labs has just released NUKE (Nearly Universal Kinematics Engine) in Beta form, which is a comprehensive and easy to use IK system built around the arbotiX Robocontroller. To make things even easier, he’s created a step by step tutorial on how to implement NUKE on your arbotiX based robot.

The Nearly Universal Kinematics Engine (NUKE) is finally out in a first beta. NUKE is a PyPose tool that allows users to setup an IK/Gait engine for their ArbotiX-powered bot, regardless of the size, servo orientation, etc (as long as it fits within an available template). Right now our templates only support 3DOF Lizard-legged 4 and 6 leg robots, however 3DOF Mammal-style leg support isn’t far off, and low DOF Biped support is in the works. This is the same system that powered Issy, Roz, and Jeff to take the top 3 spots at CNRG’s Walker Challenge. It takes about 20-30 minutes to setup your bot once you get the hang of what’s going on. The output is fairly straight forward to expand/alter. It’s mostly been running on Quads, I’ve yet to fully test it on Hexapods (first person to post a video of NUKE powering a hexapod gets a cookie at Robogames..)

NUKE is written in Python, and it exports a C/C++ Arduino project that runs on the ArbotiX. NUKE can be downloaded from our Google code site: http://code.google.com/p/arbotix/downloads/list. Documentation is also on that site. We also have a google group for support (it’s very new, hence the low traffic) http://groups.google.com/group/robocontroller .