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| |} | | |} |
| </center> | | </center> |
| ====Auto calibration before firmware version 03.25.07.Rev.00.====
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| Accelerometer auto calibration functionality has one purpose - determine how FMB device
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| is mounted in a vehicle. After the calibration process ''eco driving'' functionality becomes active
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| and calibration data will be used to determine harsh acceleration, braking and cornering events.<br />
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| There are two conditions when auto calibration takes place:<br />
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|
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| *If on device startup no calibration was detected;
| | ======Auto-calibration====== |
| *If the device receives an SMS/GPRS message with ''auto_calibrate:set'' text.<br />
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| After functionality has started FMB device periodically checks current appliance GNSS,
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| ignition and movement source parameters and if the conditions match:<br />
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| *position fix got;
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| *GNSS speed is zero;
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| *ignition is ON;
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| *first calibration vector was not saved yet;<br />
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| Then first vector is taken. Saved vector will be considered as ground vector and it will be
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| used at further calibration calculations.<br />
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| ''Note: When FMB device saves first ground vector vehicle must be parked on flat ground''.
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| Crooked vector may have an impact on further calculations.<br />
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| Afterwards first ground vector was taken, device analyses conditions:<br />
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| *position fix got;
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| *GNSS speed is at least 20 km/h;
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| *ignition is ON;
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| *second vector was not saved yet;
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| *vehicle driving in the same direction with 5⁰ tolerance;
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| *vehicle speed increase by 7km/h within 1 second.<br />
| |
| | |
| For next vector. Second vector will be taken if all conditions match. Immediately after
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| second vector is received, it will be multiplied by first (ground) vector, the result of these
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| vectors is vector multiplication cross product which is the right side of a car. By using
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| same vector multiplication method, device front, left side will be calculated. At this point
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| calibration is successfully ended as indication device sends an SMS/GPRS message with
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| ''Device is calibrated, to recalibrate send:auto_calibrate:set''.<br />
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| ''Note: SMS/GPRS message will be sent only if auto calibration functionality was triggered by''
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| SMS/GPRS message''.<br />''
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| For user convenience in case auto calibration functionality fails then notification message
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| will be sent. For exact messages, check algorithm section.<br />
| |
| ''Note: SMS/GPRS message will be sent only if auto calibration functionality was triggered by''
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| SMS/GPRS message''.<br />''
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| To get current calibration status ''auto_calibrate:get'' SMS/GPRS command must be sent to
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| the device. If device is calibrated it will respond with ''Calibration state: calibrated'' or otherwise
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| ''Calibration state: not calibrated''. Also this command returns saved Ground and Side vectors.<br />
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| After every TRIP START event, device starts shadow calibration. This type of calibration is
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| running in parallel with already saved vectors (this means that vectors does not reset until
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| shadow calibration have both new vectors). After shadow calibration is done, device updates the
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| vector values to the new ones. There are two conditions when shadow calibration does not run
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| at TRIP start event:<br />
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| | |
| *Normal calibration is still running.
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| *Shadow calibration is still running from previous TRIP event.<br />
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| To take ground vector these conditions should be met:<br />
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| *Ignition is ON
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| *Device got GPS FIX
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| *Vehicle speed = 0km/h<br />
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| Device will check these conditions every 1sec until they will pass.<br />
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| To take side vector these conditions should be met:<br />
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| *Vehicle speed >= 20km/h
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| *Device got GPS FIX
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| *Ignition is ON
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| *Device angle does not change more than 5 degrees in past 1 sec
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| *Speed need to increase by 7km/h in 1s period.<br />
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| | |
| Device will check these conditions every 1 sec until they will pass.<br />
| |
| | |
| | |
| ====Auto calibration rework and improvements from firmware version 03.25.07.Rev.00.==== | |
| | |
| Accelerometer auto calibration functionality has one purpose - determine how FMB device is mounted in a vehicle. After the calibration process ''eco driving'' functionality becomes active and calibration data will be used to determine harsh acceleration, braking and cornering events.
| |
| | |
| Auto calibration task is launched on one of these conditions (assume calibration is enabled in configuration):
| |
| *Every time device turns on, it checks whether it was previously calibrated and has calibration stored in flash. If device has no calibration in flash, auto calibration task is started.
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| *Device calibration was previously disabled by configuration and now is enabled.
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| *SMS “auto_calibrate:set” is received. Note: SMS response is sent after calibration has been acquired.
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| This SMS triggers an SMS response to be sent. Response is sent when calibration is acquired. When 1 hour passes without successful calibration, failed SMS response is sent.
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| *Calibrated device’s mean axes of set interval differ more than set amount from desired (0,0,1) calibration is considered inaccurate. Calibration is deleted from flash and auto calibration task started.
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| After auto calibration task has been started, it will go on indefinitely until satisfactory calibration is acquired.<br />
| |
| | |
| =====Auto-calibration Improvement=====
| |
|
| |
|
| Auto calibration task is launched on one of these conditions (assume calibration is enabled in configuration):<br> | | Auto calibration task is launched on one of these conditions (assume calibration is enabled in configuration):<br> |
