Arduino Uno + Big DC Motor KIT

Hi,

Are there any good motor control kits out there that are plug and play? Something you can use from the get go and vary motor speed with the arduino? The motor would need to have atleast a torque of 25nm

Motors and motor driver modules usually are sold separately. All-in-one kits are mostly for professional use and expensive.

Do you want an AC or DC motor, stepper or 3 phase motor?

The torque can be increased by a gearbox, so which rpm do you want? Fixed or variable? What feedback (speed, position…)?

Thanks for your reply.

I decided to get a MEGA with

This motor http://www.robotshop.com/ca/en/12v-28a-3333-oz-in-nema-23-bipolar-stepper-motor.html

This driver http://www.robotshop.com/ca/en/pololu-single-bipolar-stepper-motor-driver.html

Im going to power it with the MEGA using a step up http://www.robotshop.com/ca/en/12v-step-up-voltage-regulator-u3v12f12.html

Hopefully this works, never tried powering up a motor before

That step-up regulator is much too weak for driving the motor.

The motor draws much more current than the Arduino, so you should use a primary power supply for your motor, and a secondary step-down regulator for the Arduino.

Really? The tech support from the vendor said it would work....anyway it was out of stock so I went with

https://www.creatroninc.com/product/24v-5a-step-up-boost-regulator/?search_query=24v&results=22

Will this be alright? I am powering the arduino with 9V 1A wall adapter. I was going to connect the step up to the arduino to jump up the voltage then connect it to the motor driver.

Could you explain why I would need a secondary step down regulator for the arduino?

Thank you

Do you know how to calculate electric power, from voltage and current?

When your motor draws 2.8A at 12V, that's about 2.8*12=34W. Your wall adapter only supplies 1A*9V=9W. Where should the remaining 25W come from?

A step up converter will increase the supplied voltage, but not the power. When you feed 1A and 9V into the step up regulator, it can supply about 90% (efficiency) of 9W on its output, that's about 8W/24V=1/3A, far away from the 2.8A required by the motor.

That's why you should get a 12V 3A power supply, usable for both the motor and the Arduino. Then you can use the on-board 5V regulator, or another step down regulator, to power the Mega.

Thanks for your explanation!

Is there a limit to the current I can power the mega with? Could I get a 9V 5A wall adapter which could power the mega as well as feed it to the step up 24 V regulator to the motor?

Otherwise I could go with your solution.

Thanks again for your advice!

Look up the maximal supply voltage of your boards, that’s the most important limit. Some boards can work within a wide voltage range, like an Arduino usually can be powered safely from a 7V to 12V supply.

You need a power supply (from mains, or a secondary step up or step down regulator) for each voltage. Every supply must be capable of sourcing the sum of the maximum currents, drawn by the components which are connected to the supply.

Then chose a primary power supply (wall adapter…) of the voltage of the board, that draws most current from its power supply. In your case this is the motor driver board, that draws the motor current from the supply, and feeds it into the motor.

Step up regulators should be used only with low power boards/loads, that consume not much more than a few mA.

You should learn a bit more about voltages, currents, resistors and power, and how they are related. You’ll need that whenever you work with electronic modules or parts. A voltage is comparable to the pressure behind a water tap, and the current is how much water will come out when you open the tap, more or less wide. The power equals the amount of water, that flows in a given time span. I.e. you cannot get more water (power) out of a valve (step down regulator) or pump (step up regulator), than you feed into it.