Power Functions Motor Coasting

[Jim]

After building the 9398 4x4 Crawler I have been wondering about the difference in behavior between the Power Functions XL-Motor and the older Power Functions L-Motor.

My concern is about Motor Coasting. Coasting is defined as "Performing a natural deceleration of a motor when the power is removed". In layman's terms; the vehicle continues rolling a bit, until completely stopped, so no abrupt stop.

When the power on the XL-motor is removed, the motor coasts gently to a halt. However, when the power from the L-motor is removed, it abrubtly halts without coasting. This results in very shocky behavior, which I think can be done without.

Any idea why the two motors behave differently? And more importantly; is there a way to use the new L-motor with coasting behavior? Possibly with a 24T Clutch Gear or other mechanism/technique.

[nicjasno]

I'd use a one way clutch.

[MrNumbskull13]

Or the speed remote.

[zux]

I'd use a one way clutch.

But this would keep its effect if you'll drive one direction only. Am I right?

[Jim]

Or the speed remote.

I could try to use the speed remote, but I'd still want the model to behave properly when using the normal PF remote.

But this would keep its effect if you'll drive one direction only. Am I right?

I was wondering the same thing. Could you elaborate a bit on the "one direction clutch" implementation?

[skppo]

In a crawler it makes sense for the car to stop completely since it doesn't have brakes.

Clutches that enable free rolling work best on high speed vehicles.

But here is a topic on one way clutches anyway

The centrufugal one is nice.

Edited December 28, 2013 by skppo

[Boxerlego]

Any idea why the two motors behave differently?

I think this has something to do with the magnet in the motor.

[Eigenbroetler]

It has to do with the internal gearing and rpms of the motors.

[Zerobricks]

As soon as you will go downhill you will loose control of thr crawler IMO..

[Technyk32231]

I could try to use the speed remote, but I'd still want the model to behave properly when using the normal PF remote.

I was wondering the same thing. Could you elaborate a bit on the "one direction clutch" implementation?

Or you could use a setup similar to that of a ratchet wrench. You could have a clutch gear setup change the direction of the ratchet and then you could go both directions, and stop when needed.

[Zerobricks]

Here's a simple dirty try... Works good, but the 8 tooth gears tend to hit the side beams, so that needs to be fixed.