War Hawk - Scrambler (2015 Science Olympiad)

This is a steerable ETV (Egg Transport Vehicle) for the 2015 division C Science Olympiad, Scrambler. It should be fully rules complaint but check dimensions before using this design.

Note: At time of upload, the design has not been tested in competition and has no guarantee of performance.

Note: The pictures included with this design show a Launcher Backpack installed, but this is not part of the original design and is a separate download. 

=====================================================

Printed Parts needed:

1x Block Bar (Final)

2x War Hawk - Axle

2x War Hawk - Block

4x or 8x CD/DVD Hubs 

1x Egg Block (to make it a Scrambler)

=====================================================

Hardware Needed:

12x M3 6mm Square Head Bolts or M3 6mm Wing Bolts 

12x M3 12mm Square Head Bolt

2x Makerbeam Extruded Aluminum Beams (300mm used in pictured cart)

2x 1' of #8-32 thread rod

8x #8-32 Nuts

1x #8-32 Wingnut

2x 1/4-20 x 1" Hex Head Bolt

2x 1/4-20 Wingnut

2x 6" Plastic Protractor

4 or 8 CD/DVDs

=====================================================

Info on Installing:

1. Drill a 1/4" hole into the origin of Protractor.
2. [under construction]

=====================================================

Info on the Design:

(2022 thoughts on a 2015 design) The War Hawk was an upgraded design of the Speed Bird, and my attempt to create a steerable ETV (Egg Transport Vehicle) to collect bonus points available that year. The bonus would be awarded if the ETV could go around a large can of food that was offset from the centerline of the track. The War Hawk was going to achieve this by allowing the operator to set an angle of the axels so the cart could be launched to go wide of the bonus can and the then it would make an arc back towards the target point. 

Unfortunately, the War Hawk is at best a flawed design. This is because both the wheels on each axel are locked to that same axel, meaning both the inside and outside wheel were turning at the same rate. This is fine if you are going in a straight line but the moment the ETV is trying to make an arc one or both of the wheels will slip or skip. This slipping and/or skipping of the wheels caused the ETV to be very bad a making a smooth arc or hitting the target distance. 

The War Hawk can be configured to run in a straight line (and was the backup plan incase the first run failed to get the bonus) but at that point it wasn't any better then the Speed Bird. In fact it was worse because of the steerable axels would create more point of failure that could cause the ETV not to run straight. The War Hawk was uploaded before this flaw was really figured out and as the same bonus has not come up again, the War Hawk has never been fixed. 

Category: Engineering

=====================================================

Update: 

2024-02-25: STEP Files Added