The G120 can log harsh events based on accelerometer activity. These include
- Harsh Acceleration
- Harsh Braking
- Harsh Cornering
The device can be mounted in any orientation. The device will automatically figure out which way is forward/back, left/right, and up/down. The device should be mounted so that it does not experience excessive vibration or rattling during driving. Once powered, the device will begin to continuously self-calibrate. It begins from an uncalibrated state, in which the harsh driving detection is disabled, and the accident detection is in a basic mode that ignores orientation. Once the vehicle begins a trip, each time it accelerates, brakes, or turns, the unit can compare the acceleration to the GPS velocity to determine its orientation. Each maneuver increases the accuracy of the orientation, and when the accuracy is high enough, harsh driving and advanced accident detection are enabled. This typically takes 10 to 15 minutes of normal driving.
The Harsh Driving parameter is added from Parameters -> Edit System Parameters -> Add Parameter -> Harsh Driving.
The G120 has two Harsh event Thresholds marked "A" and "B" in the parameter tab. This allows for the following operation
- Threshold A set at a certain level. The device will beep to provide in-cab feedback to the driver that they have breached a threshold.
- Threshold B can then be set at a higher level, where the device will log this event as well.
- Threshold A provides a warning to the driver, threshold B is logged for reports in TG or another platform - and action can be taken to rectify these drivers behaviour.
- The above is just the intended application - yet we can use only 1 threshold, or both, beep and log on both etc.
The Duration on both thresholds are disabled by default. This means that any instantaneous event (as detected by the accelerometer, which runs at 100Hz) that exceeds the threshold will be logged. A duration can be added such that brief events can be filtered out.
We find most partners get on fine with the defaults. It is important to keep in mind that adding a lengthy duration can potentially prevent any events from being logged, so it would be best to test these settings before rollout.
An event will be logged if the acceleration exceeds the threshold for at least the configured Log Duration Threshold (seconds). A second event is logged if the acceleration drops below the threshold for the configured Log Duration Threshold (seconds) and then exceeds the threshold again for the configured Log Duration Threshold (seconds).
Configuring the beep numbers will sound the internal buzzer on the G120 (or any external buzzers connected) when an event is logged and provide the driver in-cab feedback that they have exceeded the threshold so that they can adjust their driving.
The defaults work well for most vehicle, however here are some notes on setting the right level if they need adjustment.
- Defaults: Acceleration and Braking thresholds are 4.4m/s^2, and Cornering is 5.5m/s^2. These are set reasonably high to log a minimum number of events on most vehicles.
- Testing: Set the thresholds artificially low to generate events. Acceleration and braking can be configured to 3.0m/s^2 and Cornering to 3.5m/s^2
- In practice: Choose levels between the defaults and the testing levels (i.e. start low, and slowly bump up until you're no longer getting excessive events)
Notes on Operation
- The harsh event can go off if the vehicle is on a steep enough incline (and threshold is low enough).
- The log reason 'harsh accel/brake/corner' doesn't distinguish between thresholds A and B, so you may need to use digital inputs if you log both.
- If you set beeps for both thresholds A and B, you can get an inconsistent number of beeps since both events can occur at the same time (or very close to each other).
- eg. 1 beep for A, 3 beeps for B. you will get between 1 to 4 beeps depending on the timing of the events.
- it may be better to set beeps for just the lower threshold because this must be crossed to reach the higher threshold.
Harsh Events on Telematics Guru
For TG users, Harsh Event Logging must also be configured in TG to log these events in Harsh Driving Reports. See Harsh Driving On Telematics Guru.
Different vehicles require different thresholds for triggering events, therefore it is important to test and adjust the thresholds. A large truck and a motorcycle will require very different thresholds. There is no 'magic' setting per vehicle or asset type. Instead the best way to get the thresholds correct is simply some trial and error.
If you are getting excessive alerts, just bump up the values.