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I have a motion detecting robot project. I have looked over and over it and tested the power. The sensor won't work. The robot just goes and doesn't stop.




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The activity can be viewed at: Build a Motion-Activated Guard Robot (BlueBot Project

Hi - usually when people have trouble with this project, it is because of an incorrect connection on the breadboard somewhere. It is difficult for us to help troubleshoot unless we can see your circuit. If you can upload clear, well-lit, in-focus of your circuit from a top-down view so we can clearly see all the connections, we can help spot any errors in your circuit.

The motion sensor is also extremely sensitive and can be affected by other sources of infrared light, like sunlight and incandescent light bulbs, so it can help to test the robot in a dark room/with the windows closed, facing away from you so you do not accidentally trigger the sensor. You can also put the sensor in a cardboard tube to limit its field of view.

We havedone everything you suggested and it hasn't worked. I will upload a picture of the board.

Hi - from what I can see in the picture, your circuit is correct, although I can't see everything since some of the wires and taller parts are blocking the view. If you can upload a few more photos from slightly different angles, I can double check everything. In particular there's the gray wire in the lower right of your image that starts in hole J2. That should be going to the "+" bus (column next to the red line). I can't tell from the picture if it's going to the "-" bus (column next to the blue line) instead.

Another question - do your diodes (the black cylindrical parts) have a gray stripe on one end, or is the entire thing black? They should have a clear gray stripe toward one side which indicates their directionality. In your photo, the gray stripe should point up, toward the red power bus. But I cannot see the gray stripe at all on either diode in the photo.

Finally - do you have access to a multimeter? That would allow you to test if the sensor is working properly, independent of the motors. If you have access to one I can guide you through that process.

Thanks,

Ben