Fixing Camera Failure

It is a common issue for the camera to fail to initialize when bringing up a robot. While there can be a number of reasons for this, in my experience 9 out of 10 times this error is due to the camera's ribbon cable being incorectly attached. The goal of this lab notebook entry is to give detailed instructions how how to troubleshoot this problem and re-attach the ribbon cable correctly.

Troubleshooting and fixing steps:

Step 1:

Upon receiving a "failed to initialze" error for the camera on bringup, locate both ends of the ribbon cable (the end attached to the camera and the end attached to the Raspberry Pi).

Step 2:

Check that the ribbon cable is correctly attached to both ends. (Both ends of the cable should be attached in the same way). 1. The outlet where the ribbon cable is plugged in is incut slightly, the side of the ribbon cable with a blue tip should be faced away from the side that is incut (it should be facing the wall of the outlet). 2. Ensure that the white tab on top of the outlet is pushed all the way down and that the ribbon cable is not loose. It is often the case, especially with the Turtlebots, that the ribbon cable looks attached, but that one side of the outlet is not locked in place. See the image below for an example, notice how the white tab on the right side is not pushed in fully:

Step 3:

If the cable is not correctly inserted pop out the white tab on the desired outlet by using your fingers to lift up the small knobs on both sides of that outlet. (Note it will only lift up a small amount).

Step 4:

Carefully insert the ribbon cable (with the correct orientation as described in part 1 of step 2), making sure that the cable is pushed all the way down into the outlet. It won't go very deep or click, so don't use too much force.

Step 5:

Once the ribbon cable has been inserted correctly into the outlet, snap both sides of the white tab back into place. This step can be a bit finicky as one side of the ribbon cable can become loose while snapping the other side into place, so ensure the cable doesn't become disloged during this step and that both tabs are locked in place. To verify that the cable is secure you can give it a slight tug to ensure that the cable is locked into the outlet.

Step 6:

Check your work to make sure the installed ribbon cable looks like the two images below, and try to bring the robot up, as well as verify that the image topics are publishing.

Step 7:

If you are still having trouble, it may be a software issue and I would recommend trying the steps found in this lab notebook entry