I'm working on an RC vehicle that I want to be able to drive around my garden (uneven grass) at a walking pace sort of speed. So I thought I'd order some high torque low RPM motors from ebay. The ones I ordered were these guys :
And I am running them from a 3300mAH 7.2v NiMH battery. However, they seem to have very little torque, and when connected to some 120mm wheels, I can very easily stop them with my fingers using very little pressure.
I'm guessing this is because they are under powered? and I should be trying to get closer to the rated 12v? so should I :
Double the voltage by using two 7.2v NiMH batteries, giving 14.4v?
Use a 12v lead acid battery instead?
The motors I bought also come in a 24v variety. Would that mean they would have more torque? I guess I could used two 12v lead acid batteries?
Or should I be looking into a more substantial motor? I know that windscreen wiper motors and wheelchair motors are usually used for this sort of thing, but I think that would be overkill? is there a 12v motor that is more powerful than what I have but not quite as big and bulky as the above?
For reference, I am planning on using this setup with a FlySky FS-i6 Transmitter/Receiver and a Sabertooth Dual 12A 6V-24V Regenerative Motor Driver.
Take the guesswork out and calculate or measure the torque you actually need. Then buy a gear motor with
a torque rating.
Torque in a gearmotor depends mainly on the gearing.
You need to decide the minimum top speed you can tolerate and determine the motor power from this
and the torque. power (watts) = torque (Nm) x speed (radians/s)
Basically torque is a number (ie 3.5Nm for instance), not an adjective ('high'). "High torque" is marketing
speak meaning absolutely nothing.
yeah - I have been trying to find the torque ratings, but I find they are often not listed
And I don't really even know what torque I need? Could anyone give me a rough idea? ball park figure? I appreciate it's a bit vague, but a starting point would be good.
Do you know what torque is? Then you'll understand how it can be measured and calculated...
Noone can give you any kind of a figure unless they know the details of the thing, "RC vehicle"
does not convey any numbers.
Put it this way, imagine walking into a hardware store and asking for "a bolt for my widget", and
expect them to know what size bolt. Same thing, we need the measurements...
MarkT:
Put it this way, imagine walking into a hardware store and asking for "a bolt for my widget", ..
I was once in the local engineering tool shop when a woman walked in and told the assistant that her husband had sent her in to get a good screw. Needless to say stifled laughs all round.
