Senior Projects

Bionic Arm Project

Assembly 5

Joshua Valerio created a bionic arm as the first step toward fulfilling his dream of becoming Iron Man. Joshua’s bionic arm was created after four years of FIRST Robotics mechanical team experience on Team 696 and became a project that encompassed the whole process of building, from conceptualizing and prototyping, to CAD design, fabrication, and assembly. The arm is made of wood cut with a CNC router and powered by two Denso Window motors geared down to extend or retract the elbow joint in one second and carry up to 30 pounds at 18 inches from the elbow. The product was modeled in Autodesk Inventor and imported into OneCNC to operate the CNC router used to machine out the wooden parts.

Main Assembly 2 Gearbox   View 1
After researching and sketching dozens of concepts for him arm and deciding, for example, to use motors instead of air cylinders for more control, or to use wood instead of metal for easier machining, he designed an early CAD model and 3D printed it at a smaller scale to physically see if the proportions of everything made sense. After several revisions to produce the most optimal strength and easiest machinability, Joshua used a horizontal band saw and lathe to machine the shafts for the VEX gears to ride on, soldered wires for the three-position switch, CNC routered the bearing plates for the gearbox and the arm structures themselves, and assembled it all. In total, after over 16 hours in research, 14 hours in CAD, and 20 hours in construction, Joshua spent over 50 hours throughout March and April to create his bionic arm.


Bicycle Frame

IMG_20150629_125052837_HDR

This bicycle’s frame was designed, fabricated, and welded by Vahan Keshishyan, 2013 graduate, solely using tools from Clark’s Engineering lab. He chose to build the bike as his senior project and was aided by Clark teacher David Black. After researching the benefits of various frame materials, Vahan chose to use double-butted Italian-made Columbus chromoly tubing. Vahan wanted to build a classic road inspired bike with slightly wider commuter-friendly tires with rims laced to an internal hub gear system to eliminate finicky derailleurs and long ugly chains that are necessary for cassettes and chain tensioners found on most geared bikes. He chose to use road-angle lugs that hold the tubing at a standard geometry and are traditionally joined to tubes by brazing with silver solder. However, the torch he could afford did not get the thick lugs hot enough to get the silver to liquefy and flow into the gaps between the tubes and lugs. Luckily, Mr. Black had recently acquired a TIG welder for the shop, allowing him to finish his project by learning to weld. After countless work hours during and after school, even on the weekends, the frame was completed. It is a unique amalgamation of new fabrication technologies and old design techniques. While at UCSD the next year, Vahan collected parts to build the frame into a complete bicycle with his limited budget compelling Vahan to recondition many free components from old abandoned bikes. The next summer Vahan got the frame and parts powder-coated its clean, blue and white color scheme. Finally, he assembled everything into the bike you see in the above picture. He chose to use a British 5-speed Sturmey Archer X-RD5w geared hub.