42mm High torque planetary gear motor with encoder - 24V 330RPM

Help & Support Robot Parts
1

Hi!

I require your help regarding a problem I’m encountering.

Description: I’m building a go kart for my 10 year old daughter and I’d like to know if two of these motors attached to the rear wheels would be strong enough to move the cart. She weighs about 40kg and the cart around 15kg.

Hardware concerned: 42mm High torque planetary gear motor with encoder - 24V 330RPM - RobotShop

Software concerned: n/a

Troubleshooting steps already taken: n/a

Additional information: this is the motor recommended by the project author: Mega Torque Planetary DC Geared Motor 250W 300RPM 18VDC [RMCS-2006] - ₹4,500.00 : Robokits India, Easy to use, Versatile Robotics & DIY kits

Thank you so much in advance for your help!

3

Hello @Wdjr ,

Welcome to RobotShop community.

The Rated Torque for the motor in the tutorial is 92kgcm which is so much higher than the one that you have suggested.

The closest option we have would be around 50kgcm and this would also mean less RPM.

Here’s the link for the motor:

You can use the sizing tool to know if this motor would work or not:

Let us know if you need further assistance.

Sincerely,

1 Like
4

Thank you, @Ebram.

Yes, I am aware that the motor has much less torque. But would two of them attached to the back wheels be capable of moving a child plus the car weight (approx. 55 kg), or would I be better off with two of the 50 kgcm version you suggested? 120 RPM sounds reasonable, since this would only be used for recreation in an empty parking lot. But if the 30 kgcm motor is enough for the job, I’d rather go with the higher RPM.

Thanks,

Will Dias

5

Hello @Wdjr ,

Thank you for your reply.

There are a lot of parameters that you need to fill in to be able to tell if the 2x30kg.cm would be enough or not.

You can test that using our sizing tool:

Awaiting your reply.

Sincerely,

6

@Ebram
I truly appreciate your attempt to help, but I don’t have any technical expertise and I don’t know what I’m even looking at when I fill this form.
All I know is the specs for the recommended motor and I can’t find a similar one anywhere in North America. I feel like the 50kgcm option would be good enough, but I don’t know how the other specs affect the performance. No load speed, no load current, rated current, etc.
As I said, I don’t care about it being the exact same performance, but it must move a cart with a child on it at a reasonable speed (5-10 km/h or 1.4-2.75m/s).
What would you recommend for a go kart carrying 55-60kg up to that speed?

7

Hello @Wdjr,

Thank you for your reply.

In this case, the 50kg.cm motor should work.

However, you need to make sure that the motor controller that you are using can handle at least 25A and better to be 32A like this one:

The motor should be able to give you a speed around 1.6m/s assuming the wheel’s diameter is 30cm.

Let us know if you need further assistance.

Sincerely,

8

@Ebram
Great, this has been very helpful. A couple of questions before I finalize the purchase:

  • Is there a cheaper option for the controller?
  • Does the motor lock when turned off, or do I need another means of braking/stopping the car?
  • What kind of controller do I need to be able to go forward, back, stop, and increase/ decrease the speed?
9

Hello @Wdjr ,

Thank you for your reply.

The motor controller that we have suggested provides all the control options you have mentioned above.

However, you can check other options from these links:
https://www.robotshop.com/uk/medium-power-motor-controllers.html
https://www.robotshop.com/uk/high-power-motor-controllers.html

Just make sure that the continuous current per channel is 25A or higher.

Have a lovely weekend, stay safe.

Sincerely,