Personal IDR (PIDR) is an incident data recorder built into your phone, Designed primarily for use in cars to record the events and behaviour of the car when an incident takes place. This information is invaluable when explaining what happened during an incident. For example in a collision scenario it could show that you did stop at that intersection, or it could show that you were not driving at excessive speed.
For best results the phone should be mounted in the car with the back of the phone facing in the direction of travel, although it will still function if not mounted. Once installed, or you are about to drive off, press the reset button to set the calibration of the device
In use it normally displays a car dashboard (or map of your track) and the mode of operation is similar to custom built devices in common use with many public and private organisations. PIDR detects when a significant acceleration event takes place or it can be triggered manually. To trigger manually, simply DOUBLE-TAP on the speedometer.
When triggered it records the previous 60 seconds and following 10 seconds of GPS, accelerometer and gyro data at about 50 Hz. It also records up to the last 30 minutes of GPS position data. The data is stored in two CSV files which can be downloaded or forwarded to an email address of your choice. There is also the option to display the results within the app itself and generate a PDF fie of the results. When viewing the result graphs, swipe right to expand the view and swipe left to contract it again. Tapping on each of the graphs displays the next graph in turn. For a detailed analysis of the incident you will need to download the CSV files.
Continued use of GPS can significantly reduce battery life so PIDR has three power-save options. The first keeps PIDR fully active at all times which is ideal if you want to keep the dashboard visible. In this mode connecting your phone to a power supply is recommended. There is also an option to allow the screen to dim and suspend updates to the dashboard. Finally there is an option to allow PIDR to move into the background. Data is still recorded however as it is important that you have a continual record of the motion of the vehicle and you can’t know in advance when you will require PIDR to trigger!
In all power-save modes, the system can shut down GPS if it detects that you are no longer driving. Note that if the system does shut down GPS, it can take a few minutes of driving before it becomes fully operational again. You can force the system to start GPS immediately simply by bringing PIDR back into the foreground.
* Please note that if your phone is not mounted in the car or if you don’t set the phone by pressing the Reset button, the accelerometer based speed trace is unlikely to match the GPS speed. In addition the attitude of your car driving up or down a gradient is also likely to cause the speed calculated from the accelerometer to drift away from the GPS speed. The accelerometer trace in CSV files can however be adjusted using external programs to correct for any changes in gradient. Testing on this and other IDR devices has also shown that the GPS speed trace tends to lag the actual speed of the vehicle by about 0.5 to 1.0 seconds.