1. 1 Mechanical Transducers Concept: convert power from one form to another form or effect a change in the power characteristics. Some typical devices: Gears Levers Rack and pinion Pulleys

2. 2 Gears Two power ports – key port variables Convert from rotational to rotational, but change the motion or force characteristics

3. 3 Assume gears are rigid and massless and there are no friction effects. Motion constraints:Force constraints:

4. 4 Gears – the ideal model: TF (r1:r2) T1/r1 = T2/r2 or T2 = (r2/r1)*T1 r1*w1 = r2*w2 or w1 = (r2/r1)*w2 Pin = T1*w1 and Pout = T2*w2

5. 5 Levers At least two power ports – key variables Convert from one translation port to another for small angles F1 F2

6. 6 Levers: motion and forces F1 F2 Motions:Forces:

7. 7 Levers: the ideal model TF (d1:d2) Does Pin = Pout?

8. 8 Rack and pinion v F Rotational port at pinion: torque and angular velocity Translation port at rack: force on rack and velocity

9. 9 R & P: the ideal model TF (r) Does Pin = Pout?

10. 10 Pulley with fixed axis Assumptions: no slip between rope and pulley rope does not stretch Two ports: one at each end of rope