Mechanical

The mechanical team is focused on bringing our vision for a trebuchet to life. Supported by other groups, they spend their days assembling the trebuchet itself and completing tasks like putting the trebuchet together, coming up with dimensions, and troubleshooting their build.

Timeline

5/22 : Finish cutting and preparing materials
5/22-5/23 : Apply wood onto the base of the trebuchet
5/24-5/26 : Finish the arm
5/23-5/24 : Finish the drop channel
5/24-5/25 : Finish Horizontal Channel

Early Design

Proposed by Will, this design proved to be innefective and inefficient, leading the mechanical team to create a new design that suited their needs

Final Design

Created by the mechanical team, this floating arm trebuchet was made to the sepific measurements that would ensure that we would be able to reach our goal and range.

Outdated Procedure (DO NOT USE)

This procedure is meant to demonstrate how we developed our ideas, and the process our team went through to refine and adjust the procedure

Build Procedure

Create or find blueprints online for the trebuchet
Determine the materials needed for the design
1. Gather materials for design - wood, bolts, etc
2. Gather tools for design - drills, saws, screwdrivers, etc
Construct the base of the trebuchet - see procedure below
Attach pouch by drilling diagonally with a metal pin and ting that on to the pin
Drilling another whole to tie the other end of the pouch
Add spacers through the rod and drill wholes through the medal rod to keep it in place

Base Construction Procedure

Cut 4 2x4s into 4 ft or 1.22 m length for the drop channel
Cut a 4x8 sheet of plywood into 4x4 sheets. One will function as the base
Cut a 1.4m 2x4, this will be the arm
Use one of the 4x4 sheets of plywood to make a 4x0.5 ft thick support for the arm
Make supports for the drop channels - diagonally attached to drop channel base
Sand down the arm and plywood arm support; attach using wood glue
Mark on the 4x4 plywood where the drop channel boards are supposed to go

Updated Procedure and Materials (Final)

Materials

- 2"x4"x8'
- 1 sheet of 1"x4'x8' plywood
- Wood screw and wood glue
- 5/6th inch thick metal rod
- Stripped tire wheel

Tools

- Electric saw
- Manual saw
- Electric drill
- Computer
- Triangle straight edge
- Clamps
- Writing device

Safety equipment

- Safety equipment (bandages, gauze, etc)
- Gloves

Plywood

Cut the 4'x8' sheet of plywood into 2 4'x4' sheets. One of these will be the base and the other will be cut into smaller parts to be used in the future

Support Beams

Make diagonal supports for the drop channels

Drill 2 holes in the bottom of the diagonal support, where it will be touching the base, these holes will be used to secure the supports to the drop channel and main body.
Drill one hole in the middle of the support beam, where it will connect to the upper portion of the main body

Make vertical supports for the drop channels

These supports are 2x4s, each measuring 10 inches in height, create 4 of these, placing a pair behind each set of support beams.
When the time comes, these will be glued to the back of the drop channel beams, and then the beams will be screwed into the supports

Drop Channel

Cut 4 2x4s into 4 ft length for the drop channel
Drill 4 holes into the bottoms of the drop channel beams, where screws and wing nuts will secure it to the main body
On the beams, drill 3 small holes, each above the last, these holes will be used to secure it to the body of the trebuchet

Arm

Cut a 1.4 meter long 2"x4", this will be the arm
Cut the 4'x4' sheer of plywood into 4'x1/2' thick to strengthen the arm
Sand down plywood arm and 2"x4"x4' wooden plank; glue them together after sanding

Track

Cut 8 2x4s, each measuring 23 inches in length
Once cut, drill 3 holes in the top of the wood, where it will connect to another 2x4
When the top piece is finished, take one more 2x4 and attach it to the other, creating an L shape, drill screws into the top piece, connecting the two
In the bottom of the L shape, the track will connect to the main body beams of the trebuchet
On the side of the trebuchet where the diagonal supports face, you will drill 2 holes into the track and support beams of the trebuchet, where the wheel and bar will go into

Method and Materials

Our project has proven that our design was successfully implemented, with some significant revisions applied to our method through the process. Our team started the project by collaboration with the Data people to decide the approximate dimension of the treubuchet. We then started to cut wood pieces to fit the dimensions of the frame. Soon we faced debates over how will our construction roll out whether we should first decide the width dimension or to start construction for one side first which we did. However, this process consume too much time so we have to divide our team and work in parallel. One worked on the base, one on the pouch and another on the arm. Then we located and drilled one side and start construction for the base. Then to meet our circumstance of making it collapsable, our main frame is attached to the base using wing nuts and screws. This process of establishing the frame lasted until the 25th only a few days before the planned launch, so we had to delay the launch to the final day. On the 26th the arm was fully contructed waiting for the pouch to be attached. On the final day the first of June we made finally touches to the main rod by securing it in place with spacers. That night we also tied the pouch to the machine. On the second, we launched the machine and did five tries. The most successful was the first try reaching 59 meters. From the second one the launch angle started to increase leading to reduced range. The second try also started to have the main able being scraped by the weights, leading to a decrease in performance. For the most part the machine has met it's preset goal. However, the design was too compacted, leaving little room for the machine to adjust. So this caused the machine's efficency decrease leading to minor malfunctions. These problems could be addressed by revising the overall design to leave room for the machine to adopt and adjust.

Page updated

Report abuse