Page 141 - Making things move_ DIY mechanisms for inventors, hobbyists, and artists

Chapter 5 Mechanical and Electrical Power, Work, and Energy 121

11. Spin the wheels backwards (clockwise in Figure 5-12) while guiding the fishing
line so it wraps around the dowel. When you get almost to the end, keep
winding the axle as you lift the mousetrap arm and flip it over.

12. To set the mousetrap, bring the long hook over the arm and catch it on the
“bait” hook. This takes a delicate touch sometimes. Watch your fingers!

13. Once you’ve set your mousetrap, you’re ready to race! Set it down on the
floor and use a pencil or other long object to trip the mousetrap. The fishing
line attached to the arm will pull on the line wrapped around the axle and it
will start to unravel. Your car should be able to go about 10 ft with this design.
Now try some variations and see if you can get the car to go faster or farther!

References

1. Dan O’Sullivan and Tom Igoe, Physical Computing: Sensing and Controlling the
Physical World with Computers (Boston: Thomson, 2004).

2. Gordon McComb, The Robot Builder's Bonanza, ed. Michael Predko (New York:
McGraw-Hill, 2006).

3. US Environmental Protection Agency and US Department of Energy, ENERGY
STAR site, “How Much Light?” (www.energystar.gov/index.cfm?c=cfls
.pr_cfls_lumens).

4. Nicolas Collins, Handmade Electronic Music: The Art of Hardware Hacking,
Second Edition (Routledge, New York: 2009).
5. Jeff LeBlanc, “ALDEH 300 Energy Harvesting Modules”
(http://itp.nyu.edu/physcomp/Notes/ALDEH300EnergyHarvestingModules).

6. Michael Lindeburg, Mechanical Engineering Reference Manual for the PE Exam,
Twelfth Edition (Professional Publications, Belmont, CA: 2006).