Gyroscopes are frequently used in physics lecture demonstrations and in laboratory activities to teach students about rotational dynamics, namely, angular momentum and torque. Use of these powerful concepts makes it difficult for students to fully comprehend the mechanism that keeps the gyroscope from falling under the force of gravity. The analysis of gyroscopic motion presented here is in terms of linear forces and linear momentum, allowing students to understand gyroscopic motion using familiar concepts. Our simulation using VPython1 models the gyroscope as a number of point masses evenly spaced in a radial pattern. Students can alter the parameters of the gyroscope including starting position, mass, rotational velocity of the masses, and the force of gravity. All of this allows for a simulation intended to help students understand how such a complex system works.

Topics
Gyroscope, Friction, Rigid body dynamics, Rotational dynamics, Educational aids, Teaching, Lectures
2.
Ernest F.
 
Barker
,
“Elementary analysis of the gyroscope,”
 
Am. J. Phys.
 
28
,
808
(
1960
).
https://doi.org/10.1119/1.1936009
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3.
Consider the linear velocity of each mass due to an infinitesimal precession, freezing for the moment the rotational motion. In general V=Ω×s⁠, where s is the position vector of each mass. Thus, the linear velocity of mass G and H due to precession will be greater than that of masses D and E:|VG,H|=Ωd⁠, where d=R2+r2 and |VD,E|=ΩR⁠. These equations hold when the four masses are arranged as they are in Fig. 1, with a horizontal precession and no nutation. This effect was taken into account in the VPython program but was not included in the paper as this is a second-order effect, (Δd)(Δt). Only first-order effects in time were considered in the paper.
4.
See supplementary material at TPT Online,
https://doi.org/ 10.1119/1.4849150
.
© 2013 American Association of Physics Teachers.
2013
American Association of Physics Teachers

Supplementary Material

Supplementary Material- zip file
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