What proper BLDC motor and encoder can be used in Odrive v3 34v

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1

Hi, I bought 24V ODRIVE V3.

My target is to use ODRIVE to control my robot arm (which already has 4 DC motors(24v) and 4 potentiometers)

my question：
is what kind of BLDC motor can be used in ODRIVE？
potentiometer can be used in ODRIVE? if not, what kind of encoder can be used?

my motor datasheet is
DC 24v
ratio 1:150
current <=0.35A
no load current <=100ma

my potentiometer show below

微信图片_20230505110910
微信图片_202305051109101080×796 123 KB

2

Hi,

You will need to use a 3-phase BLDC motor with the ODrive. We offer a handful of these motors on our shop, and here is a list of tested motors. In general, the ODrive can be configured to work with most hobby/professional BLDC motors.
Unfortunately you cannot use a potentiometer as an encoder. Incremental or Hall Effect encoders work great, and there are a few supported SPI encoders as well. Checkout our encoder guide for a detailed list.

1 Like
4

Hi, Nicholas,

thanks a lot!! it is really helpful information to start with ODRIVE.

there is a question about encoder:

you mention if only support with incremental encoders,
so how could find zero position, if ODRIVE restarts? what is normal method?

for zero position problem, this is also the reason why I use potentiometer.

thanks!

Rob

5

For absolute position you’ll need to use one of the supported SPI encoders:

  • from CUI Devices: AMT232A, AMT232B, AMT233A, AMT233B
  • from ams OSRAM: AS5047P and AS5048A

You can find links for these encoders here, and wiring/config instructions here.

6

thanks Nicholas.

I understand every new installed motor or encoder need to go through Odrive configuration step, but which parameters in motor and encoder need to be configuaration in Odrive?
these parameters can be found in motor datasheet?
any example?

thanks

7

For the encoder the only thing you really need to know is the cpr (4x the Pulse Per Revolution (PPR)
For the motor you will need to know:

  1. pole pairs. This is the number of magnet poles in the rotor, divided by two . To find this, you can simply count the number of permanent magnets in the rotor, if you can see them.

  2. Torque Constant. This is the ratio of torque produced by the motor per Amp of current delivered to the motor. This should be set to 8.27 / (motor KV) .

  3. Motor Type. This is almost always HIGH_CURRENT, unless you are using a gimbal motor.

All of this should be easy to find in the datasheet.

Also, you can find configuration instructions for the ODrive here.

1 Like
8

thanks a lot! very useful

9

Hi, Nicholas

one question for the torque constant.

8,27 is a general parameter for odrive or the value is depended on which motor I use?

I had a little bit confused about torque constant setting.

thanks

Rob

10

There’s apparently a short answer and a long answer to that question, I prefer the very short answer of “It’s a magic number that works for all motors” and accept it. The maths in the short answer gave me a headache :sweat_smile:

More info here:

2 Likes
11

love the short answer.