WedgeHook (TM)
In my Product Design and Innovation Studio 3 course, I was given a design task to "make the studio classroom better.” With minimal project constraints, I began asking questions about the usability of the large room. Through questioning peers, and observing the use of the space, I concluded that we needed to identify a way to maximize the available open areas. Specifically, book bags had no place to be stored and were in fact a hazard as they were strewn on the floor. The WedgeHook was conceived as a a way to use previously unused space available under the design lab tables. WedgeHook is designed to fit on round table legs, be self-supporting, easily removable and reusable, and strong enough to support a bag full of books.
Initial CAD Model
A next level CAD model described my ideal model of the device. WedgeHook has two
outer shells, one with the hook and one for support, with three wedges able to be spaced evenly throughout the interior of the shells to provide the neccessary force to support the weight of a backpack and prevent shifting. The purpose of seperating the outer shell into two parts is to improve application. In order to apply the device, the table does not have to be lifted to slide the shell or wedges into place. Though it increased the number of pieces, it reduced the frustration of lifting the table to apply and move the device.
WedgeHook Iterations
The outer shell went through five iterations:
1. Proof of Concept: Able to suspend a PVC cylinder on a table leg.
2. Addition of Hook: First test of concept, slippage occurred after 10 pounds of application.
3. Finished PVC Model: Able to support the weight of two full college backpacks (45 lbs) without slippage. Painted black to match the color of the table leg and improve visual appeal.
4. Design Change 3D Printed Dove Tail (orange): Remodeled with two pieces connected by dovetail joint. No hook for strength testing, the purpose of the model was to test ease of application.
5. Finished 3D Model (black): Held under 30 pounds until spectacular failure of dovetail joint.
The wedge went through four iterations improve the weight capacity:
1. Proof of Concept: Expendable material (rubber bands, foam, rubber mats) to suspend the model on the table leg with two small wedges for final movement prevention.
2. First Wedge Test: 3, 3D printed supportive wedges coated with rubber spray with a taper to ensure the wedge would at least fit under the ledge enough to create a wedge effect.
3. Wedge Refining: 3 supportive wedges coated with rubber spray with a refined taper to hide as much of the wedge as possible and improve the aesthetics of the hook
4. User Experience Improvement: One flexible 355 degree wedge 3D printed using a Formlabs 3D printer and flexible resin
Dovetail Tolerance CAD
Physical Dovetail Testing
Physical Dovetail Testing
Dovetail tolerance testing occured on a small scale as there can be a little bit of variance with 3D printing.
Physical Dovetail Testing
Physical Dovetail Testing
Physical Dovetail Testing
In order to ensure a smooth fit on the final test model, I tested multiple materials and printing methods. The final model was printed using a Formlabs resin printer.
User Testing
Using the PVC model, I received feedback from numerous users of the Design Studio with mixed feedback. Some users experienced slippage upon application while others did not. One student decided to take the apparatus apart and set it up on another table to test the usability and functionality without guidance on use. Feedback included difficulty of application due to multiple parts which inspired the idea behind one flexible wedge reducing the ideal model to 3 parts instead of 5 parts.