Cab Position and Movement

Since tapping into the elevator control system will not be possible (see August 11 post) we will be using sensors in the cab to detect position and movement. This information will then control the sound files. My initial thought was to use an arduino microcontroller with an accelerometer to sense the cab movement and try to keep track of what floor we are on by counting stops. This will require "homing" the system at, say, floor 1. Here is a data log graph of a test I made using an accelerometer in the elevator of our condo building. Although somewhat noisy, there are clear spikes for starting and stopping. Seems promising but accuracy over time is my concern.

Here's the patch I made for this test using Hans-Christoph Steiner's Pduino object/firmware and Chris McCormick's [s-totalrecall] PD abstraction to record the data.

My other thought for detecting elevator position and movement is to optically read the display inside the cab. A combination of techniques may be necessary. More on that in a future post. - Drew