It's Bananas

by Mick

We have Joysticks, Light Pens, Digital Pens, various types of Game Controllers, Keyboards, Mice, Touch Devices, Image Scanners, Barcode Readers, Smart Cards, Speech Control devices and now the Kinect.

But why can't you use anything as an input device?

To explore the concept further, I chose an item I found lying around in the kitchen and here are the results.

Does it fit on the desktop?


It has a number of different orientations that can be used perhaps the most common being horizontal.

or it can be held in a vertical orientation

I discovered that the horizontal orientation was the most comfortable and was also the best when held in 2 hands which provides greater stability when manipulating the device.

So the object itself is suitable, how do we turn it into a working device?

How to make it work

Bluetooth is not going to work and neither is a direct wired USB connection, however I found some software which enables you to track a brightly coloured object using a web-camera.

The software will track the longest axis of an object and this is used to determine the orientation. The center of the object is determined by intersecting an axis across the width of the object with the longer axis. The center point is used to calculate the position of the controller in the plane of the PC screen e.g. the position of the cursor when emulating a mouse.

This approach allows you to easily emulate a mouse using the object and you can simply rotate to the left to simulate a left-mouse click and rotate to the right to simulate a right-mouse button click.

Watch it in action driving the SolidWorks 3D CAD Modeling Application.

If you look carefully you will notice the tracking symbol superimposed by the software on the object.

This was created by the software as a virtual tracking symbol and is not something actually taped to the object!

Required Components

  • 1 Brightly Coloured Object
  • Web-Camera
  • CamSpace software
  • SolidWorks or other Windows Application

For more information about CamSpace check their web-site at