Manufacturing and Assembly

As seen in the previous pages, the team implemented the many possible improvements identified from the first prototype into the CAD design of our device. We then ran complex analysis on the kinematics of the linkage and made small changes to achieve a smooth, frictionless motion for our linkage. With the final design completed, the team began to manufacture our final prototype.

Keeping in mind the goal to improve craftsmanship from our first prototype, the team decided to machine all of the components for final prototype. This began by building the entire structure that the table would eventually be mounted too. We purchased stock T-slotted aluminum profile to build a strong base structure. The aluminum profile made up our three legs to support the entire device and was modified through machining to add additional holes for mounting the motor and our many adapter plates. We then fabricated a wood box and backboard in the wood shop in order to provide both support and storage carrying capacity. 

The majority of the fabrication time spent on the final prototype was in the machining of the linkage and various mounting brackets. We initially had all of our links (including the table halves) water jet but several of the hole tolerances were too poor for press fitting. Therefore, we had to remake a few of the links via CNC. We also had to make several custom modifications to the table halves. The first was milling out the center of them to drastically reduce the weight of the mechanism. The other was adding custom mounting holes for the attachment of brackets and bearing holders.

Many custom brackets were fabricated for this project as well. In order to attach our linkage to our table halves using shafts and bearings we had to make custom bearing holders that mounted to the underside of the table. Along with these, we also made custom brackets to attach one of our gears directly to the table. This piece was heavily designed in order to obtain a precise mounting location. Finally, the team also machined custom pins or shafts to match the specific lengths needed for our mechanism. These pins included small grooves to attach clips in order to prevent the links and bearings from shifting during movement of the mechanism.

Figure 1: Linkage after CNC milling