The beginning design of the robot was very basic and unguided. I knew I wanted to build sophistication into it, but what and how much was unknown. My first and primary goal was to demonstrate the application of passive dynamic robotics, which uses a highly efficient mechanical structure to minimize the need of actuated joints. Robots like ASIMO (Honda), use servo motors to achieve walking capabilities. The goal of this robot was to achieve that same motion on a higher level of efficiency.

For several weeks I designed various aspects of the project, such as hands, fingers, and rotational hip controls. I finally decided on a name for the project, SIGMO. Not only was it memorable, it was easy to say and I designed an acronym for it. SIGMO stands for Synthetic, IntelliGent MObility, capital letters denoting the acronym. At this point it became apparent that designs I had in mind would require the enlistment of several other people. People became more interested in what the project held after a name was given, because it showed more direction and promise. Up until that point, most people wondered why anyone would start on a science fair project a year before the due date.

Project SIGMO was slowed down for a short time as the end of school grew near and we were bogged down with events and activities. Shortly into the summer it was proving difficult to keep in touch with everyone. Happily, we have now devised a system which allows us to communicate rapidly and more efficiently than ever. Purchasing this website was an exciting experience for the group, as was our first listings in search engines such as Yahoo, DogPile, SearchSight, and several others- just look up "sigmo". The design phase was about 1/2 over, as I had many designs, now I just need to start implementing them and adapting them as needed. It was proving difficult to accomplish this as we live in a VERY rural area with limited access to the types of resources we needed to complete a project of this magnitude.

So I continued to develop different aspects of the design, all the while worrying and wondering how I was going to pull this off. It would be a shame to make it this far and not finish in time because of technicalities. Not finishing was not an option, as I planned to continue this project as far into my future as possible. Finishing in time for competitions was the main concern at this point.

The initial arm design was scaled to a full size human. The total robot height was to be approximately five feet high, closer to 4'10". After the proof of concept for the mechanical arm linkage was built, I redesigned the arm to be more streamlined and aesthetically pleasing. I then began construction on the aluminum torso/ chassis. The chassis utilized simple shoulder mounts which incorporated only 1 DOF. In order to reach through more space, I needed to add more DOF in the shoulder.

After three weeks of building SIGMO, the torso was completed and one full arm was built. While researching humanoids online, we realized a partial redesign was in order. I had forgotten to incorporate one of the DOF in the shoulder. I did not have enough servo motors to rebuild the shoulder with the amount of torque it would require, so I decided to completely redo the entire design. I downsized the robot to under 3 feet tall. This had numerous advantages over the full scale design.

For starters, because of the smaller size, each segment was also lighter. This resulted in reduced power consumption and also freed up motors that had previously been doubled in joints. The new arms incorporated most of the degrees of freedom a human has. The smaller size also resulted in less material usage, meaning lower overall build cost. The actuators in the legs could also be reduced in size and power, citing further efficiency enhancements.