Magni move oppositely

#1

Hi All,

I have set up my Magni robot and my workstation. ROS is working connecting to my network.
But when I drive my Magni using rosrun teleop_twist_keyboard teleop_twist_keyboard.py or using Robot Commander or even using rviz, my Magni moves the opposite direction with my command.
For example, I click the forward button in Robot Commander and my Magni robot move backward.
Is there anything that I missed out?

Thanks

#2

Hello Jack,
Sorry things are backwards. Lets look at a couple things so see what went wrong.

Did you just get your robot and does the main board (MCB) say it is version 5.2?

Next lets verify the wheel cables got connected properly at the factory.
3/4 of the way down see the picture saying ‘Main Power Battery Installation’.


From the perspective of sitting in the magni looking forward verify that the cable that starts on the right of the board goes to the right wheel. Then the cable that comes from the left side goes to it’s nearest wheel.

After that verify your firmware version and date using ros topic /diagnostics as per the ‘Checking ROS /diagnostics’ section and get firmware version and date for me please. https://learn.ubiquityrobotics.com/firmware-upgrade

We will take it from there, thanks for your help to sort this out

#3

Hi Mark,

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Yes, i have just get my robot at the beginning of the month and the MCB version is 5.2.

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I have attached my robot’s wheel cables image for your reference. As what I can see is the right cable of the board is connected to the left wheel and the left cable from the board is connected to the right wheel.

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Here is my firmware version.

Thanks for your help

#4

From your picture it looks like the motor cables are going to the wrong sides.

Using your picture and your labels you need the cable from the right of the board to go to the wheel on the right. In the same way the cable from the left of the board must attach to the wheel on the left as well.

This will resolve your issue.

Did you get this unit wired like this or perhaps in doing some working on the unit they were connected as your picture shows as the unit was re-assembled.

Thank you,
Mark

#5

Hi Mark,

I get this unit wired like this when the robot is shipped to my company. I only assembly the camera and sonar board to the robot.

I try to attach the cable from the left of the board to the left wheel and for the right wheel as well.

Thank you for your help.

#6

I thank you very much for reporting this. We will follow up on this with the final assembly process. This is extremely important to get fixed. We do have a final test so this points to a need to very clearly state the direction of turning required in the test. Perhaps somebody new on the line or something but we must improve our process to prevent this in the future. Thank you and sorry for the trouble.

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#7

Hi Mark,

I’m able to solved it by attaching the cable from the left of the board to the left wheel and for the right wheel as well. Thanks for your help.