Bluetooth Link Tests

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The table below describes the tests performed with the Arduino board in order to test the robustness and limitations of a bluetooth link in real environments. These tests are performed a few times and approximate ranges are provided in the results.

Table 1. List of tests to be performed

Summary Procedure Result
Maximum connection distance Pair the arduino board with a bluetooth device and physically test how far the devices can be from each other before connection breaks In order to establish a connection, the devices must be within 4-5m. A failed attempt will cause bluetooth.BluetoothError: (112, 'Host is down'). If a connection is established, the bluetooth devices lose connection after around 5-6m without interference. It seems that by spamming the keys on the host, the connection distance is reduced, but this could also be because of hand positioning. The host usually takes around 15s before the red disconnect light starts blinking. The receiver may take from 0-30s more before it throws a bluetooth.BluetoothError: (110, 'Connection timed out')
Maximum idle time Pair the arduino board and send/receive data in increasing intervals until connection breaks. It seems that if within range, there is no timeout. It may take around 15s if they are out of range.
Auto re-connect Once connection is lost, test the conditions under which automatic re-connection can occur. A disconnect is not instantaneous. Data might be lost if the devices are out of range, but if they are then brought within 3-4m of each other before any of them registers a timeout, then the connection is reestablished and no errors are thrown. However, if the red light starts blinking, the they will not reconnect by themselves.
Noisy wireless environments Test all the above parameters within noisy wireless environments. A xbox controller trying to connect to the xbox placed in the same room as the bluetooth devices will severely impact the distances where connections can be made. Reliable connections can be made down to half a meter, but anything further is a hit and miss, sometimes disconnecting constantly, sometimes having a 50% chance of disconnecting depending on how close the controller is to the devices, and sometimes just positioning. Once a connection is established, the controller seems to have no impact on performance.
Wheelchair field tests This set of tests will determine the basic operating conditions and limitations in the user's environment TODO