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General Misc => Misc => Topic started by: macbook on August 16, 2009, 03:19:07 AM

Title: Abt DC motor
Post by: macbook on August 16, 2009, 03:19:07 AM

I am working on a ladder climbing bot.
While the motor is off, I want it to remain stationary. Is it possible in DC motor? I want its axle to stay at its position when no current passes thru it. Which motor will serve this purpose best? DC motor (Geared or non-geared) or Stepper?

Title: Re: Abt DC motor
Post by: SmAsH on August 16, 2009, 03:24:23 AM

with a dc motor you can brake it, just short power across the two terminals.
for ease of control i would go with a geared dc motor, but it all depends on your needs.

Title: Re: Abt DC motor
Post by: benji on August 16, 2009, 05:43:42 AM

Quote

While the motor is off, I want it to remain stationary. Is it possible in DC motor? I want its axle to stay at its position when no current passes thru it

Unfortunatly DC motors will drag big current when the load gets bigger and they start to heat, plus their velocity will decrease.

Quote

Which motor will serve this purpose best? DC motor (Geared or non-geared) or Stepper?

In order to not drag any current at all and save power while there is a backward force affecting the shaft the trick will be in the gearhead.
get a DC motor with a one-way gearhead, this will allow roation in the forward direction while suppressing any backward force.

Title: Re: Abt DC motor
Post by: wil.hamilton on August 16, 2009, 04:57:08 PM

you could always use mechanical braking ;)

Title: Re: Abt DC motor
Post by: Soeren on August 19, 2009, 05:33:15 AM

Hi,

Quote from: macbook on August 16, 2009, 03:19:07 AM

While the motor is off, I want it to remain stationary. Is it possible in DC motor? I want its axle to stay at its position when no current passes thru it. Which motor will serve this purpose best? DC motor (Geared or non-geared) or Stepper?

Any kind of motor will do, as long as you use a worm gear.