Final Project, II: Decisions

       The next week, we had a number of decisions to make. We needed to fıgure out how we were going to achieve the motions we wanted, what material we were going to use and who was going to do what. A fair amount of emailing and some in-class discussion led to results. We decided that we would use ultrasound sensors for detecting people and triggering eyeball, eyebrow, eyelid and head rotation. We had initially considered cameras but found out that ultrasound sensors are much easier to work with. We also decided that we would build a face out of Delrin sheet and cover it with a mask of some sort. Ping-pong balls were the material of choice for both eyeballs and eyelids. The inner structure was to be built out of Lego. Then, we discussed who would do what. Since we had three people who showed clear interest in a specific part of the puppet, we thought dividing the project by parts would be the most efficient. I was really excited about the creepy speech so I took on the jaw and speech programming. Marie was into making crazy expressions and winks, so she stook the eyelids and eyebrows. We had just watched the famous scene from the Exorcist and Christine took the eyeballs and the head. We wrote out a plan of action for the next weeks up to the fınal exhibit.
       Next step was building Lego models of our puppets. We each built an individual structure, which at the end we were able to put together for our presentation. I built a jaw that opened by an up and down mechanism using a Picocricket. I was trying to minimize the number of motors and NXT bricks we use because they are large and take up too much sapce to fıt ın a head. I also explored other options that were available to us, like servo motors. However, my model showed me that we needed a hinge mechanism, rather than up-and-down, for a more realistic puppet. This meant that I needed to be able to control the angle that my jaw would open to for producing speech-like angle variation. This eliminated the other options and made it clear that I needed to use an NXT motor. Christine built eyeballs that slided in their sockets and Marie had eyelids and eyebrows attached to them. Our model looked quite impressive at the time we presented it to the class. It also provided us with valuable information on how we should proceed. After this point, I focused mostly on my individual duties while Marie and Christine worked more together. Their parts moved in concord and they depended on the same stimuli so they wrote their code together. I only know the basic principle behind their program and have seen it only a few times. From now on, I will talk mostly about my own contribution to the project.