I had a chance to build the iitsii Robugtix hexapod and took some time to play with BigFoot Inverse Kinematics engine that comes with the platform. The engine really simplifies the gait management with the six legged platform. The build was easy, even though you have to manually position 18 servo motors by hand. The documentation is great and includes a serial command reference if you want to do some arduino interfacing work.

three_001.jpgOne of my many Lego NXT project ideas is to build a Rocker-Bogie system similar to the Mars Sojourner, Spirit and Opportunity rovers. It turns out a similar mechanism is ipresented by Brian Bagnall in his book titled Maximum Lego NXT: Building Robots with Java Brains.

While I wait on that book to move from my Amazon wish list, to my shipping list, I found a few interesting videos:

And a site by Kevin Knuth where the rocker bogie suspension has already been built. Kevin’s site has a few more video examples.

Here is an idea I have been playing with for a little while. Instead of simply doing a car with regular steering, I wanted to try a split chassis design where the front of the car rotates in the direction you want to turn. Here are two attempts, but I abandoned any further design after driving both around with my phone via bluetooth. The steering is too inaccurate to use for an autonomous robot, but it is fun to drive.

The other night I was researching building a balancing Segway like robot with the Lego Mindstorms NXT kit. I wanted a robot that could balance on two wheels and could move forward and backward. I also wanted the robot to recover when “pushed”.

I was familiar with Steve Hassenplug’s Legway built on the Lego RCX platform, but I wanted to tackle the challenge with the NXT. Luckily, I found Philo Hurbain’s NXTWay. I was intrigued enough to build a copy and try out the programming.

It is quite hard to get the balance right and in the end I created a very aggressive robot that I can push around and it will mostly right itself. Here is the video of the final creation.

I have been working on a few different designs for a holonomic drive robot. A true platform like the other killough platforms made from Lego would probably contain wheels that rotate differently, but I wanted to publish this design because it is interesting.

I tried two different versions that you can see in the movie below. One version uses wheels but I also built this platform into a three legged walker.

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