What is your problem?

Someone keeps borrowing my desk tools and not returning it. 

 

What are your needs?
A sensor device that detects if someone is walking near my desks makes alerts. 

 

How do you imagine it to work?

It would be a tripod mounted sensor that oscillates left and right to scan for a person.

 

How do you want the device to alert you?

Make a beep noise.

 

Why do you want this?

It’s based on a robot from the video game Team Fortress 2. I want it as a desk piece and I'd like to know when someone walks into my room.

 

What area do you want to scan for a person?
The entrance of a doorway, about at 90 degree area.

 

How far back do you want the sensor device to be from the door?

Doesn’t matter, but it should be able to scan the door regardless.

 

How big do you want it to be?

Maybe about the size of a water bottle.

 

How fast do you want the sensor mechanism to oscillate?

Maybe one back and forth oscillation every 2 seconds.

 

Observations:

The end user’s problem is that his desk tools go missing. He has suggested wanting a mechanical sensor device to detect if anyone is near his desk.
 

I was thinking of putting a sensor to alert when the users drawers are opened, but he suggested an oscillating sensor that monitors the door. A servo motor could rotate a platform that holds a sensor. Gear reduction could be used to put less stress on the motor. In addition, the user would like to have the model look like its video game counterpart.