Why are you asking the same question again? Are you now planning for a different design from your previous proposal?
Giving RPM input to a DC Motor Speed Controller
If it is still the old design, the answer is still the same: you don't need to detect the engine's speed. You could possibly read the engine
load from the vehicle's CAN bus and send it to a controller by CAN.
Dear Brian, Thanks for your all previous inputs... I am basically a mechanical engineer and so bit confused regarding electronics side. So allow me to compile all my thoughts and concerns here. Hope you can clear following few points:
TARGET: My ultimate target is to run a DC Brushed or Brush-less Motor on 100% same RPM (WITHOUT ANY DELAY) as of Vehicle's Engine RPM (on engine's different loads)
1- Either I can take running Engine's RPM from a Tachometer with RS232 out put or Tachometer with CAN signals out put (which I have not found yet) or with Crank shaft sensor's output voltage. If you have better suggestion then please share.
2- You are saying that I should not be worried about the SPEED/RPM rather I should be more concerned about LOAD/TORQUE of the engine. As far as your this point is concerned the Curtis 1244 DC Motor Controller already handles RPM/SPEED as well as LOAD/TORQUE of the motor. So, do I still need to be worried about syncing LOAD/TORQUE of the Engine with the motor?
if YES, then exactly HOW and with WHICH electronic device I can instruct DC Motor Controller regarding engine's LOAD.
3- If you would be in my place and to achieve above required TARGET, what would be your exact approach?
MY APPROACH (based on current studies, may be it still requires a lot of further input):
1- Detect engine's RPM via Tachometer with RS232 output.
2- Build a RS232 to CAN signal converter (eventually this conversion kit may cause a very little delay in communication (forwarding LIVE RPM value to DC motor controller).
3- RS232 to CAN signals converter will give CAN signals to the DC motor controller.
4- DC motor controller will run the motor on required RPM and LOAD
Thanks