Part A, Baseline Mechanism
You are on a design team working on a robotic mechanism and have been assigned the analysis of part of the mechanism. The part for you to analyse is shown below. This linkage has an actuator at point A that needs to apply a couple at point B of up to 2.5 N m. The angle range at point B is from 20 to 120 degrees. You need to determine the maximum torque (couple) required of the actuator at point A and the minimum length of rod AC.
For the project you will plot the results for the length of AD, the force of the collar on AC at D and the required moment at A to keep the mechanism in equilibrium as functions of the angle at B. The approximate solutions with the angle at B equal to 20 degrees are:
- Length of AD = 78 mm
- Force of the collar on rod AC at D = 17 N
- Couple at A = 1.3 N m
Part B, Modified Mechanism
The lead designer would like to move the actuator at A 100 mm to the left. You need to analyse the new mechanism with the distance from A to B now modified to 250 mm.
You should:
- Identify and define known information.
- Draw the Free Body Diagrams of the rods BD and AC as well as the collar at D.
- Identify the information you need to find.
- Outline a solution procedure to find the information required.