Experimental determination of gyroscopic couple

A spatial mechanism commonly employed for the control of angular motion of a body is called Gyroscope. The resistance to change in the direction of rotational axis is called the gyroscopic effect. The torque or turning moment, that opposes any change of the inclination of the axis of rotation of a gyroscope, is called gyroscopic couple. Or in other words, whenever the axis of a rotating body is caused to change direction, a couple is required, called as gyroscopic couple. The reaction to this couple is experienced in aircraft, marine and car engines when changing direction and is also employed in navigating systems. In the present study, a motorized gyroscope apparatus is used to evaluate the active and reactive gyroscopic couple. The apparatus is made up of a brass gyroscope flywheel mounted in a cradle which allows the flywheel to pivot in the x, y and z directions. When the gyroscopic couple is equal to the couple applied by the counterbalance weight; the arm of the gyroscope will run in a horizontally. When the arm of the gyroscope is horizontal, the speed of precession and the spin speed have to be recorded. Knowing the mass properties of the flywheel in addition to these speeds, the gyroscopic couple can be estimated experimentally. From the mass of counterbalance weight and the radius of rotation, the theoretical couple that can be produced by the apparatus can be evaluated. Reasonably good agreement was observed between test and theoretical results.