Motor necessary to power a small cart

[dracalb]

Is a 6.5kg/cm torque motor enough to move (let.s say at 6km/h) a small go cart and a kid (total w. about 45kg)?

this is the motor: http://www.amazon.com/dp/B00T48KC1Q/?tag=pfamazon01-20

PS: this is not for a homework but for a for-fun project.

 

[OldYat47]

Right offhand I'd say no. It looks like the RPM is 200, and I'm assuming the torque is 6.5 kg-cm(?). So available torque at 1:1 ratio on a 25 cm diameter tire would be about half that, or 3.25 kg-cm. To get to 6 km/hr with the same tire you would need about 3:1 speed increase, which would reduce the torque to about 1.1 kg-cm. With all the other considerations (rolling resistance, elevation increases in common roads, even flat ones) I don't see it working.

Anyone else?

 

[CWatters]

Power = Torque * angular velocity
Power in Watts
Torque in Nm
angular velocity in rads/s

200rpm = 200*2*pi/60 = 21rads/s
6.5 kg.cm = 0.64 Nm

So that motor develops...

Power = 21 * 0.64 = 13W

Google says Kids carts typically use 500W motors and adult carts 1500W.

So way too small.

 

[CWatters]

Try a 500-1000W scooter motor. I think they use 36V so you also need 3 * 12V batteries and a 36V controller.

http://www.ebay.de/sch/i.html?_odkw...cooter+motor.TRS0&_nkw=scooter+motor&_sacat=0

 

[jack action]

What is important is the power rating of the motor. As @CWatters calculated, there is a 13 W output (it is actually 9.4 W, since the rated RPM is 140 rpm and not 200 rpm). This is a replacement motor for a ride-on of this kind and it is rated at 170 W; so a lot more. And it is cheaper than yours!

 

[WaterEngine]

@jack action - This is great info!