Mechatronics (ME-503 (A)) - Important Questions

A Proell governor has arms of 300 mm length. The upper arms are hinged on the axis of rotation, whereas the lower arms are pivoted at a distance of 35 mm from the axis of rotation. The extension of lower arms to which the balls are attached are 100 mm long. The mass of each ball is 8 kg and the mass on the sleeve is 60 kg. At the minimum radius of rotation of 200 mm, the extensions are parallel to the governor axis. Determine the equilibrium speed of the governor for the given configuration. What will be the equilibrium speed for the maximum radius of 250 mm?

Define and explain the following terms relating to governors: Stability.

Define and explain the following terms relating to governors: Sensitiveness.

Define and explain the following terms relating to governors: Isochronism.

Define and explain the following terms relating to governors: Hunting.

What is the stability of a governor? Sketch the controlling force versus radius diagrams for a stable, unstable, and isochronous governor. Derive the conditions for stability.

In a turning moment diagram, the areas above and below the mean torque line taken in order are $4400,\ 1150,\ 1300$ and $4550\ \text{mm}^{2}$ respectively. The scales of the turning moment diagram are: Turning moment, $1\ \text{mm} = 100\ \text{N}\text{-m}$; Crank angle, $1\ \text{mm} = 1^{\circ}$. Find the mass of the flywheel required to keep the speed between $297$ and $303\ \text{r.p.m.}$, if the radius of gyration is $0.525\ \text{m}$.

Explain the terms 'fluctuation of energy' and 'fluctuation of speed' as applied to flywheels.

What is the function of a flywheel? How does it differ from that of a governor?

A cam consists of a circular disc of diameter 75 mm with its centre displaced 25 mm from the camshaft axis. The follower has a flat surface (horizontal) in contact with the cam and the line of action of the follower is vertical and passes through the shaft axis as shown in Figure 1. The mass of the follower is 2.3 kg and is pressed downwards by a spring which has a stiffness of $3.5\ \mathrm{N/mm}$. In the lowest position the spring force is 45 N. Derive an expression for the acceleration of the follower in terms of the angle of rotation from the beginning of the lift.

A cam consists of a circular disc of diameter 75 mm with its centre displaced 25 mm from the camshaft axis. The follower has a flat surface (horizontal) in contact with the cam and the line of action of the follower is vertical and passes through the shaft axis as shown in Figure 1. The mass of the follower is 2.3 kg and is pressed downwards by a spring which has a stiffness of $3.5\ \mathrm{N/mm}$. In the lowest position the spring force is 45 N. As the cam shaft speed is gradually increased, a value is reached at which the follower begins to lift from the cam surface. Determine the camshaft speed for this condition.