Determining camshaft deceleration rate from Follower?

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AmazingTrans
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I am doing this as a hobby, trying to understanding some physics calculation for camshafts and following cam s,v,a,j.
All pictures in this thread are just samples that tie to nothing much, other than just images.

p34.png

7y94hR.png


1. From the 1st image above, the camshaft (emulated digital signal) is moving at a "constant speed", and the follower (motor) has the following plot. The camshaft has no boundaries in terms of velocity, acceleration, or jerk since it is digitally emulated.

I also have included the follower (which is a motor) properties. (Yes that's a tesla S motor. =D ) As we can see, the higher the speed of the motor, the lesser torque.

If the follower/motor is running at 120 mph and only capable of "d Nm" (reduced torque),
At point #2 of the cam plot and the camshaft decided to stop at a specific rate "x".
What would the camshaft deceleration formula look like if I want the follower/motor to not exceed 75% of the torque curve at that point ?

My goal here is to use to constantly change the camshaft deceleration rate such that the follower does not ride along its torque curve all the time.
 
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I just thought, another good example of this application would be like today car (Nissan) where they use regenerative braking to brake the car.
If they were to run the car at higher speed, they have limited torque at that point. I would think the controller would constantly change its deceleration rate such that the motor follows the torque curve of the motor until it reaches low speed, then it will apply higher deceleration rate (more torque) when it is at lower speed.
 
There seems to be something missing in your system description. How can a motor be a cam follower? I've done a lot of work with cams, but I've never seen anything that I would describe like this. Could you give us a sketch of the system you are talking about, please?
 
AmazingTrans said:
I just thought, another good example of this application would be like today car (Nissan) where they use regenerative braking to brake the car.
If they were to run the car at higher speed, they have limited torque at that point. I would think the controller would constantly change its deceleration rate such that the motor follows the torque curve of the motor until it reaches low speed, then it will apply higher deceleration rate (more torque) when it is at lower speed.

Torque at high speed is probably limited because max power has been reached. I'm not sure if max power is limited by the motor or battery on the Tesla.

I can't think of a reason why, under regenerative braking, the torque should be limited to exactly same curve as under power.