I've been working with an art student at Emily Carr University to design and build one piece of a bigger art project, Code.lab. Makiko's project is to build a "robot" that follows the metal railroad tracks that run around Granville Island and in front of ECU. We first looked at line following robots to inform some of our decisions around the form for the sensors, the motor and wheel arrangement, and the general shape of the final artifact. Makiko's desire to shape the aesthetic to her artistic vision is definitely helping with material and part choice, but the various versions of prototypes that we built together helped to create objects that we could discuss and use as a platform for ideation.
The first real prototype, past sketches, was a Lego Mindstorms line follower. We were able to observe how an optic line follower worked, with a single sensor on the front of the robot detecting the black color of the line against a white surface.
The next version was an arduino based line follower that we thought we would use Hall-Effect sensors to detect the metal rail tracks with. We took a small prototyping step here to test the Hall-Effect sensors which we discovered were overkill for what we wanted to do. In the end we chose to use rare earth magnets mounted on the arms of contact switches to detect the metal tracks.
Prototypes informed our choice of wheel clearance relative to the robot chassis, helped us determine that the sensors should be mounted on the front of the robot. Testing versions of code helped me come up with the final code that drives the servos to follow the metal tracks.
Every prototyping step helped us refine an abstract thought to a more certain form, a form that functions in a way that is close to what we had originally envisioned. Versions of the parts of this project let us look closely at our problem space and also exposed problems that we had no idea existed. We were able to physically discuss and evaluate our design decisions, considering Makiko's artistic vision and the pragmatic need to make this robot move and follow the tracks. We are now at a prototype version which is very close to the final form - new parts in the coming weeks will bring us to the final scale. It will be interesting to see what the final form looks like come February when the final exhibit opens to the public. Stay tuned for more of our progress.
