In 2003 we started to work on a sled based on a 203 4-stroke Arctic Cat. The Arctic Cat 660 4-Stroke uses a modest engine to produce a good workhorse 4-stroke snowmobile. One approach to add interest to the design would be to put a bigger engine in the snowmobile. However this incurs costs in fuel economy. A different approach was taken with British sports cars of the 1950's and 1960's. Cars such as the Lotus 7, the Berkley and others used standard engines as small as the 900cc Austin to produce a car that ran with the supercars of the time. This tradition continues in the Chaterham 7 or even the modern Lotus. As the Lotus web site puts it:
"The most elegantly effective and traditionally Lotus solution is the one with the least number of parts effectively deployed"
These cars are the model for the clean sheet design of the UMaine Clean
Snowmobile. Novel design of the structure will be emphasized while making
use of as much of the existing sled design as possible. design should be
based on open wheel and sports car racing. The Redline snowmobile also
showed some innovation that may be worth reviewing.
This is not a construction oriented project. The final result of this project will be a detail design and fabrication techniques and resources that will need to be obtained or developed. More of less work can be done on the resulting design by the team, but the focus is on design not build.
Milestones:
 | Proposal for modified milestones and initial deliverables: September 15, 2005 |
| Initial design concept sketches review |
| Measure pick up points for carry-over design components |
| Complete solid model of pick-up point |
| Schematic complete of snowmobile structure with pick-up points |
| Presentation of first semester results: December 6, 2005 |
| Solid model of advanced structural design complete and ready for poster presentation at competition |
| CSC Competition, March 13th -18th, 2006 |
| Solid model complete for final design |
| Detail drawings of all attachment points and components |
| Set up of projects for final review, Maine Day: May 3, 2006 |
| Open house, operational review of project: May 4, 2006 |
| Final Project Report due: May 10 2006 |
Milestones:
| Measurements of current sled (9/20/05) |
Take measurements of current snowmobile, including attachment point locations for the engine, driveline, and other major components necessary.
| Preliminary webpage design done (10/4/05) | ||||||||
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Basic Chassis Design criteria and
improvements (10/18/05)
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| Chassis design Sketch (11/01/05) |
Create four basic design sketches for the chassis incorporating the improvements we have deemed necessary over stock chassis. Basic line drawing showing frame and MAJOR pickup points
| Create solid model of chassis design (01/24/05) |
Create a three dimensional chassis model using SolidWorks.
| Determine idealized loading for competition sled (11/30/05) |
Analyze usage of sled in competition, determine dynamic and static loading of the snowmobile including separate forces exerted on the chassis by the engine suspension and other major components
| Presentation of first semester results (12/06/05) |
| Determine design loading (01/24/06) |
Using the idealized loading data, determine a safe design loading matrix
| Apply design loads to chassis (02/01/06) |
Utilizing the finite element method, apply loads and determine appropriate building materials and final chassis design, ie diameter and structure of tubing, bracing, and joint structure.
| Refine and reiterate design to maximize performance described by design criteria (03/01/06) |
| Detailed drawing of all attachment points and components (03/15/05) |
Create a final drawing package for the fabrication of the chassis.
| Final report outline complete (04/01/06) |
| Final report completed (04/18/06) |
| Open house, operational review of project: (05/04/06) |
| Final Project Report due (05/10/06) |
