Overall we realized that it was going to be a crunch to finish it in time, and spent long hours in the shop working on it, but were able to complete all of the parts in time for the deadlines.
Out of our 3 major modules, 2 worked.
The major failure, or the most apparent, was in the driving wheels. A lot of things went well about this: all of the shaft holes lined up, the drive wheel layout had the right dimensions to keep the tank treads in tension. The major problem was that the shafts did not attach to the wheels. The driveshafts were hexagonal and the wheels had a hexagonal slot. By design, torque should have transferred and they could have worked. Our failure was in ordering the wrong size bearing. The shafts did not fit, so we had to make them smaller. We thought we would be able to glue the shafts in to the wheels, but that did not work. Were it not for that one tiny detail, the wheels would have worked.
The paddle wheel turned out okay. We failed to consider a few things in designing it. First, we assumed that since it didn't need to carry a large load, we didn't need a high gear ratio. But as a result, it spun a little too fast and we had to be careful when using it. We also could have secured it from translating horizontally a little bit better. It did stay in place, but if you ran the motor really fast (which you shouldn't anyway), the gears would disengage. Overall though, it did work and was able to collect and dispense balls.
The biggest success was our MCM, the swinging hook arms. We made a homemade drive belt to work with the extra drive wheels from our tank tread set in transmitting the torque to the rotation shaft. It meshed properly with the teeth on the wheels and worked very well, thus the arm moved as intended. The arm also swung perfectly in the geometry we wanted it to, not swinging two far or tilting improperly at all.
Here is a link to our full bill of materials, including the cost of extra materials we purchased during the project
No comments:
Post a Comment