Dyno Design Help

[runandrew]

I'm creating a test setup similar to a dyno and am trying to detect the torque from a motor shaft. I am using an Eddy Current (EC) Brake to absorb the torque coupled from an engine.

 

 

Below is a rough sketch of the test setup. The brake will be centered on a plate that is allowed to rotate on one side and is supported by a load cell on the other. Can you guys help me with the statics of finding T_1 (Torque from the motor) knowing the values of W, L and F_y.

 

Thanks!

[Enthalpy]

Torque sensors exist and work. Any development would cost you much time before you get a sensible result - and your design has known weaknesses in it.

 

So: why shouldn't you buy a torque sensor instead? Some exist that you put at the shaft, and don't even need an electrical contact between rotating parts.

[John Cuthber]

T2 needs to be a load cell too. (or at least, that's a more conventional set up because it's a whole lot easier to work with.)

Edited October 31, 2011 by John Cuthber

[runandrew]

In respect to cost, a torque sensor can be very expensive. I am looking for a low-cost solution.

 

Enthalpy - can you expand on the known weaknesses of my design?

 

 

Also, to solve for T_1 by summing the moments about the hinge point (taking counter clock-wise as positive)

 

---

-T_1 - T_2 - W*(L/2) + F_y*L = 0

(T_2 = 0, no external torque input)

So,

T_1 = F_y*L - W*(L/2)

---

 

Is this correct?

Edited November 1, 2011 by runandrew