I encountered a lot of problems today that we would be dealing if we continue on using the wrong materials. We cut the hard wood that we had yesterday in some circle sections from biggest to smallest. After we had cut all of it, we compiled all the wood that we cut and realize that it's going to be heavy in terms of the motor that I was thinking we will use. I talked to Sam (3rd year student) whose good on building mechanical stuff and he also thought that as well. We should have gone for a plywood or an acrylic material so that the cable wires can hold it together. He's not sure if those cable wires can hold the hard wood which is really too thick and heavy that it would need a much thicker wire to be able to stand. One thing he suggested for the wire is either we could use a hose for holding the wooden plates and put marbles on the hose. Marbles would be flexible enough to bend since it's rolling inside. Another thing he thinks it would be the best is to make a thread out of a cable wire and make it thicker. He also suggested another that it might work, a motor that sticks on an oval shape structure and there's going to be a lever that would stick on another shape structure near the base of the tentacle. It's like a train wheel that's going up and down. But after I showed him what I saw from the youtube where they use motors as a pulley, he thinks that method would be better for us since we want something that is more controllable.
In terms of motion design, I bought a dc motor in surplustronics today which is a big one and have high torque speed.
At first I was doubting if the motor would be too much as the speed is really fast and it would not be a good motion for the animatronic tentacle plant to execute. Then another realization came to me. A dc motor can only change it's direction and speed but not the momentum. Then I thought of using a stepper motor. Stepper motors are more efficient when it comes to control. I saw some video that using a stepper motor is more efficient and it has quite controllable rather than a dc motor.
I ask Tom Drake (2nd year) if he has some stepper motor and he does have one but he doesn't suggest to use it for what we are making. It might not handle enough strength to pull some strings in the pulley since he already had some experience on using it. He suggested to use a big servo which can handle 5 kg's of weight and it's more efficient in coding. Another option that he told me is a gear motor that can handle the same weight of the big servo motor. But it would need an h-bridge to handle it and it would cost a lot for those materials. As for me as long as we have the correct materials to use even if it's expensive, it would be fine to spend a lot since it's a good investment for the project. One last thing that he told me that we could use as a support material, a spring wire in the middle section of the tentacle plant. It is flexible and it could help a lot on supporting the frame when it's bending
I guess I have a lot of options to go when it comes to building it but it would matter in the end for the story and the character that we're going to make and it could be more easier and efficient to build it than I think if we could agree on the motion of the character that it suppose to do.
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