LED Failure
(ancillary risk) |
That particular band of the display will simply be dead until the LED is replaced. |
Rotating connector provides two conductor connection between the stationary base and the power supply. What if the connection is interrupted, even briefly?
(show stopping risk) |
Very low pass filter is used to filter noise and small jitters on the power line. If the connection is broken for more than a short instant, the device will immediately reset. |
One of the Serial I/O Expanders fails
(ancillary risk) |
All LEDs on that module will be dead until the module is replaced. |
Motor Failure or Rotation Sensor Failure
(show stopping risk) |
Buffers are swapped on the rotation sensor interrupt, so the image will freeze on the display. The CPU timer may detect an unusual rotation speed and shutdown. |
Failure to update the frame buffer before the next revolution / refresh (as indicated by the rotation sensor interrupt). NOTE: This might be caused by radio interference, issues with the PC software, or some other similar event.
(ancillary risk) |
The frame buffer is double buffered. The buffers are not swapped until a complete buffer is received from the PC. If the signal is lost, or the data rate drops to unacceptable speeds, the video will stutter or freeze. |
Vibration
(ancillary risk) |
The platter will be evenly balanced, with coounterweights if necessary. The frame is much heavier than the platter and designed to mitigate vibration. |
How do you transfer data between a rotating platter and a stationary PC?
(show stopping risk) |
We considered using an IRDA link through the hollow, rotating shaft, but settled on 3.0mbps Bluetooth link (UART over Bluetooth) |
What if the platter rotates too quickly or too slowly?
(ancillary risk) |
Sensor on the platter measures the exact rate of rotation (interrupt on each rotation). The user may adjust motor speed with an analog knob (variable resistor). |
