Solid Oak Lifter

In Engineering 10B we were assigned to come up with an adjustable ramp so that we could aim a vehicle and guide it precisely into a skee ball target for various point values. I undertook the task of designing and fabrication the lifters for making the ramp adjustable, to make matters more difficult, everything had to be made from a natural material, so metals and plastics or other composites were out of the question. I though of a peg and slot style design but then realized that it is too inaccurate since each increment relies on where each spot is drilled. Every animation and drawing here is done in Solidworks and rendered in Photoworks.


The lifter design that I ultimately went with was a rack and pinion design. This allows for maximum homing in of the correct angle to propel the launch vehicle to the center of the target. The drawing here depicts what one side of the lifter would look like upon completion. There will ultimately be 2 lifters and a connecting rod between them.

Solidworks assembly file

  This is the exploded view of the components to represent how everything assembles together once the parts are fabricated. It clearly shows the sprocket gear and the rack that will be moving the lifter up and down.
  The completed assembly will look something like this. notice that the gears are joined together by a solid wooden connection rod so that the level of the lifters will be level with respect to each other. Also the knob that will assist in being able to crank the rack up and a stopper to hold the assembly in place once it is position in  manor that we chose. The square pieces on the top of the racks are the pieces that will slide against the ramp and provide a sturdy and large contact area.

Solidworks assembly file

  The exploded view shows how the other pieces are assembled with respect to the lifters. the lifters are tied together at 2 points to minimize any unevenness that could possibly occur while it is being cranked up or down during adjustments.
  Here are the pieces after some manual and CNC machining is done to some raw oak material (the crank handle and support is not pictured). There are still several areas that need to be finished by hand then the assembling begins.
Once the ramp and the lifters are assembled separately then joined together into one structure the result looks like this. The ramp is made of a pegboard material and you can clearly see the guides in place to guide the launch vehicle into any location that we want it to go.
  This is the launch vehicle, we decided to go with a vehicle that already has side rollers so that there is minimal frictional loss before the vehicle makes it to the launch ramp. As you can see in the picture the grounding tabs at the rear of the vehicle cause the wheels to life off of the ground at one point on the ramp. We ended up trimming the grounding tabs off to avoid that problem.
  This is the exploded view animated to maximize the visibility, as well as clearly demonstrate how the lifter is disassembled and assembled.




This is the target into which the launch vehicle had to land in order to score points. Our groups design ended up scoring the first in the 4 groups in our section and second overall in the total points across the other class sections. We learned that there is a certain amount of randomness during the flight and position of  the vehicle; so many times it bounced off of the top of the target.