Engineering Projects/StrandBeest/Howard Community College/spring2012/p3550cf

Problem Statement
To attempt to complete the StrandBeest or at least pave the way for easy success in the future.

Team Members

 * Brianwcallaghan

Summary
This team began as 2 and became one. The Beest was partially built, but stalled due to a flaw in the crank shaft. The next team to work on this will have only to work on a more stable crank shaft.

Story
This was to be the completion of the Beest. We ran into some trouble with the crank shaft. The glue I was using proved to be strong enough for the connections, but does not do the job of wood filler. In the first weeks of this round, the circles were designed and the design for the crank was nailed down. Drawings were done and the crank parts were cut on the CNC router at Maryland Sound Intl. I lost a week due to illness, but got back on track shortly thereafter. The 4th week was very busy. I used it to continue the build, which failed. I also took the time to make a very detailed tutorial so the next group on this project should be able to complete it.

Decision List
Week 0
 * Assembled parts for legs and assessed what needed to be done to get it moving.

Week 1
 * Tested dowel sizes and methods of attaching.
 * worked on Keying holes and dowels.

Week 2


 * Cut parts for crankshaft on CNC router.

Week 3


 * Got very ill. Was not able to get much done.

Week 4
 * Continue build.
 * put together crank
 * made tutorial.
 * filled out team page.

Material List

 * 1) 2 sheets of.25 inch masonite (for circles)
 * 2) 1/2 " wooden dowel 3 foot
 * 3) 3/4" wooden dowel 2 foot
 * 4) Leg assemblies and parts from previous project attempts.
 * 5) Wood Glue
 * 6) Saw
 * 7) Drill w/ 1/2" and 3/4" bits

Software List
AutoCAD 2012 was used to do the design of the wooden parts of our StrandBeest. AutoCAD is computer assisted drawing software. Its purpose is precise design.

EnRoute 4 was then used to import the AutoCAD files (saved as .DXF) and prepare for output to the MultiCAM 3000. EnRoute is CAM software. The function of CAM is computer assisted manufacturing. It communicates your drawings and the details of how your parts are to be cut/drilled to the machine which does the cutting. In EnRoute, you can import CAD files, edit them, draw from scratch, set toolpaths, and select cutting tools and order. EnRoute can communicate with and export executable information to most CNC routers, laser cutters, water cutting machines, 3D printers and such equipment.

Time
41 hours

Tutorials

 * Building the StrandBeest (with Crank Shaft)

Next Steps
The crank shaft remains the main hurdle at the moment. I had some luck with the circular shape, but I did not properly key the connections, and the particle board failed. This design is good. The only real issue is that the connections on the crank shaft need to be made stronger to withstand torque. Wood filler can be used to fill the keys rather than glue. This will be an improvement. The working Beest will need to be powered. Wind is the obvious choice, but other avenues could be interesting as well. The existing kit is missing two legs. The strength of the legs and the ability to water proof them, run it out side and survive on pavement means that the entire strandbeest needs to be rebuilt with different material but the same design.