overview
As a school project, we were assigned the task of designing a "Launcher" system which would deploy an "Orbiter" from earth (marked in blue) which would then have to autonomously deploy a variety of "Landers" into the gravity well. I was in charge of designing the Launcher.
process
Sketch. Launcher.
The concept sketch I initially came up with. The thought was to design a push plate that would translate along two metal rods via linear bearings. The push plate would attach to springs fixed to the front of the Launcher and transmit the spring force to the Orbiter.
Sketch. Push Plate.
The push plate had two primary functions; it needed to translate along the metal rods and needed to transmit the elastic energy to the orbiter.
Two holes allow the plate to slide along the rods and two strategically carved out, protruding tips allow for the springs to attach to the push plate.
Sketch. Base Plate.
The elastic energy from the extended springs would cause a significant amount of torque and therefore reinforcement was necessary to enhance rigidity. Additionally, the springs needed somewhere on the main launcher assembly to hook onto.
The plate screwed on to the bottom of the launcher providing the necessary structural integrity. The small slit on the flap of the plate is where the end of the spring opposite the push plate attached.
The unfolded outline of the base plate. 90 degree bends at the marked locations would give the plate its final form.
Materials.
Wood was used for as much of the construction as possible due to its environmental sustainability and lightweight yet durable properties. Metal was only used where necessary like for the linear bearings, springs and base plate.
Machining.
A waterjet cutter was used to create the flattened outline for the base plate. 14 holes were then precision drilled into place using a milling machine for the screws to fit slightly recessed below the bottom surface.
Woodworking.
Given the precise alignment needed for the metal rods to fit through 3 wood pieces, I used a waterjet cutter to make the wooden pieces. Later we realized the push plate was over constrained and only 1 bearing was needed which left more room for misalignment.
The holes were all precision drilled using a milling machine.
Release Mechanism.
The competition day was in 2 days and we had not figured out how to accurately maintain different spring loaded positions for easy and smooth disengagement, My solution was a metal bracket which attached to a recess in the push plate and had equally spaced holes. A single pivot locking pin with a 90 degree bend for finger placement was attached to the back plate.
Final Prototype.
This was the final prototype with our orbiter fit snugly inside the launcher.
One of the metal rods and linear bearings was replaced with a wooden dowel and plastic bushing to address the previously over constrained design.
Although difficult to see in this photograph (but visibly shown in the final product below) custom L-brackets were made to further increase rigidity. They were placed on either side of the back plate attached to the two long bottom pieces.
Result
