BU sculpture professor Sachiko Akiyama came into the EPIC studio asking for help regarding designing and building a kinetic sculpture. She had a small motor and gearbox assembly with a battery pack, and wanted something which waved two arms back and forth using gears. The reason for this project was to show her sculpture students what materials they could use and how they could go about achieving motion. I told her how my parents are both potters and I come from an artistic background, and that I would love to work on this project for her. I wanted to get an eclectic mix of materials in my sculpture so that the students could have a good example to work off of. We have 3D printers, metal shaping equipment from files to CNC mills, and a laser cutter at the new EPIC stuido that I work at.
I started off by working with Sachi to refine her customer requirements, and my twist was to make the "popsicle" stick arms she had explained into something that created more of an interesting aesthetic show. After we both decided what she really wanted, I started to model everything in Solidworks, with the renderings presented below. Basically the motor assembly sits on top of a blue 3D printed housing which gives height clearance to the large 3D printed drive wheel. This large gear meshes with a smaller 3D printed gear which spins a shaft. The shaft actuates the lasercut clear acrylic drivearm assembly on the right hand side of the motor assembly housing, forcing the lasercut wooden "hand" to wave back and forth. The smaller gear is also connected to a 3D printed drivearm assembly on the left hand side of the motor assembly housing forcing the 3D printed mirror-image "hand" to wave.
The most frustrating part of this project was after 3D printing my parts which were meant to simply snap together, the material was unexpectedly brittle so the pins sheared off right as they were about to clear the hole. I tried to reprint the parts on our other 3D printer because I knew that the PLA material they used was significantly more bendable, but they were all broken at the time and this project was due in a few days. I ended up finding a plastic shaft that happened to be the same diameter as the broken pins so I wanted to drill holes of the appropriate size in my 3D printed parts so that I could easily epoxy the sculpture together. However, even trying to drill into the 3D printed parts destroyed most of the parts, so for example I ended up making a unique aluminum metal piece for the 3D printed "hand" base that ended up tying the whole project together in my opinion.
Sachi brought her class in, she loved my kinetic sculpture, and it really succeeded in giving the students a good idea of what they could build!
The front view of the assembly.
The top view showing all the materials.
The rear view showing the acrylic drivearm assembly. I decided to use interference fits with a dowl pin to form the axle.
The entire backside of the kinetic sculpture assembly.
All the lasercut components lasercut and assembled! On the left is the smaller gear shaft with two plastic bushings to reduce friction that will be inserted into the motor assembly housing.
3D printing the remaining pieces using our new Objet printer.
The finished 3D printed pieces with all of the support wax still on them.
The finished and cleaned 3D printed parts with all the pins broken off. This material was simply too brittle.
The final assembled kinetic sculpture!
