Final Project Idea

1.)

As a senior design project, I helped build a modification to an existing open-source 3D printing project called RepRap, which is built along the lines of the "machines which build the machines" concept.  It has some limited self-replicating ability in that it reproduces all of the plastic parts of which it is composed, by FDM (fused deposition modeling).  In addition, their are steel connecting rods, a wooden platform, electronics including PCBs, steppers, wiring, optical endstops, etc.  An impediment to its future progress is the current lack of interchangeable heads.  For instance, it is unable to print objects with overhangs of more than 45 degrees because it lacks a real-time method of changing to a filler material extruder head.  In addition, when a head is created capable of depositing low melting temperature metals i.e. Fields metal, real-time changing heads are going to be needed to print a PCB, a necessary step in the expansion of self-replicating machines.  My project idea would create a mechanism for changing the heads, perhaps swiveling them upon a shared axis.  In turn, it would interface with the software, based off of Java3D on the Ubuntu platform, to allow the heads to be toggled on a layer by layer basis, building a more complex part.  This project is a bit more ambitious, as I would concurrently need to upgrade the model we built, which was not to spec, but rather cobbled together from pipe and acrylic, with somewhat different electronics. 







2.)    

I have an electric skateboard, and it's incredibly fun and really can get one around.  However, it has a hand-held wireless remote which is large and clunky and detracts from the experience.  Instead of using RF control, install piezoelectric force sensors on the front and rear trucks, the differential of which feeds an algorithm on a microcontroller, which in turn feeds a PWM signal to a brushed motor controller, driving the motor.  The principle of weight adjustment to accomplish propulsion is in this way similar to the Segway.  This would take some more skill to ride, and the control scheme is not trivial and must take into account bumps, turns, grades, etc.  Ideally the controller would be modifiable by a simple GUI to adjust key parameters such as control constants or weighting factors.  In addition, replacing the SLA batteries with LiFePO4 chemistry is something which I had already researched, and which may require molding a separate housing.  In this way, at least two of the planned class assignments, molding and microcontrollers, could contribute to the completion of the final project, which may or may not include replacing the batteries, depending on time.  I already have most of the expensive components.  Tasks would include designing or specing a microcontroller, coding it, building an ebox with all of the components mechanically robust enough to handle the shock of skateboarding, possibly coding a GUI to modify the control scheme i.e. user-specific schemes, maybe some physical changes to the board itself, and anything else which strikes my fancy.