Week 12

Machine Week

Assignment:

design a machine that includes mechanism+actuation+automation
build the mechanical parts and operate it manually
document the group project and your individual contribution

Tasks:

ideate and general machine design
linear axis build
rotary axis build
frame construction
end effector
electronics assemble
programming

Design

Fabrication

Linear Axis and Frame Build

After the linear stage had been assembled and a team had begun work on the software interface to the axis, another team began work on the rotary axis underneath. We decided to mount a stepper underneath the linear stage and then to attach a turntable directly to the stepper shaft. We used a small plastic bushing drilled out to the right size to give the turntable clearance from the support bracket.

We laser cut an acrylic bracket to mount the turntable to the motor shaft. It turns out that the laser cutter does not do a good job at cutting holes with precisely vertical edges, so we cut the holes a bit small on the laser cutter and then drilled them to fit the shaft snugly with a drill press.

We thought it would be convenient to be able to remove the turntable easily to mount a new sheet of paper or canvas, so we mounted a circular pad from a sticky rubber sheet on the turntable to provide a friction clutch against the acrylic bracket.