A4WD1 - Best motor with encoder for autonomous SLAM navigation

Lynxmotion Rovers, Sumo, and Tracked
1

Hi,

Several years ago I bought the A4WD1 Autonomous Kit, which at that time didn’t have the encoders.
I would like to replace the motors with motors with back shaft or with included encoders.

I saw something like this: https://www.robotshop.com/en/lynxmotion-12vdc-200rpm-078kg-cm-ghm-16-w--rear-shaft.html
But I’m wondering if there are not other motors that might suit my needs better.

The robot is used with ROS and SLAM navigation, so it doesn’t need to move quickly (1m/s is more than enough) but it needs torque in order to be able to turn in place on any surface at low speed.

What would you recommend ?

Thanks in advance.

2

The motors used in the A4WD1 have a standard mounting pattern, “Spur Gear Motors” here:

Many motors in the spur gear category have this same mounting pattern:
https://www.robotshop.com/en/spur-gearmotors.html
… as do many in this category:
https://www.robotshop.com/en/gear-motors-with-back-shaft.html

Be sure to select one which offers the same or higher torque at around the same rpm.

If you select a GHM series, the suggested encoder is:

The motors used in the A4WD1 kit w/encoders are:


Might be good options (untested):


3

Thanks for the answer !

The Lynxmotion GHM motors would be the easiest option for me, however the Lynxmotion encoder seems not to be of best quality according to user comments and the price of the GHM motor + the encoder is much higher than most of the other motors w/ encoder.

On the other side, the other options you mentioned look great, but I have to connect them with my Sabertooth RC 12V motor controller (which btw only accepts 12A) or I have to change the controller.
Are there better controllers than the sabertooth on which we can directly plug the 6 cables of the motors you mentioned ?

Thanks in advance !

EDIT: I had a look at almost all the motors with encoder, and based on the torque and rpm I need, I selected this one:


Will it fit in the a4wd1 ? Is is possible to buy the plug with longer cables ?

4

I bought the motor I was mentioning above.

I fits the A4WD1 perfectly and the encoder is working well too.
I’m still wondering what’s the name/type of the 6pins plug, because I would like to buy spare plugs or eventually ones with already longer cables.

Thanks in advance

1 Like
5

Did you manage to implement a good Slam odometry with this motor encoder combination?