Truck Lift Gate

This was a project my Mechanical Engineering Design class. In small groups we were tasked with inventing a mechanical product that addressed a real need, and faced meaningful combined loading scenarios during it's use.

This is the idea I developed for a hand winch powered lift-gate that can secure to any truck's hitch receiver. The intent is to address the the gap in the market between large industrial grade hydraulic solutions and much less capable consumer approaches like hoists and ramps.

While the real work in this project will be the FEA, motion analysis, and materials selection that is still to come, I think the first few weeks of development show some interesting process.

Preliminary Brainstorming:

After deciding to pursue this idea, I wanted to get a better idea of the motion involved at full scale, so I made this constrained sketch based on actual truck dimensions and 2" square tube steel commonly used on vehicle frames.

1:1 Scale Motion Study

When I was happy with the basics of the full scale version, it was time to adapt it into plans that I could make a scale mock-up out of. I landed on 1/4" laser cut plywood, and rebuilt the model, this time into a full assembly.

Assembly for Wooden Mock-Up

Once the scaled down version was complete, I saved out all the parts I would need to complete it and flattened them into a laser cutter template using AutoCAD. Assembly went smoothly, though there were some clearance issues with the 4-bar linkage that limited range of motion. This and a couple other fitment and clearance issues have already been documented with a plan to correct them for our next, more advanced prototype.

The next steps in this project involved building another, improved mock-up, then conducting an in depth analysis of each part and joint to consider failure modes, cycle life, and maximum deflections using manual FEA calculations. The following images show some my hand calculations that were used to provide quantitative justifications for our design.