Template:FMX Ver4 Accelerometer Based Features: Difference between revisions
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Crash Eventual record and Trace records can have a new IO element '''Crash Counter“ (AVL ID 317)'''. In addition to ''Crash Counter, Crash Trace'' must also be enabled in order for the functionality to work. Crash Counter connects the eventual crash record with its trace packets meaning each eventual crash record will have '''ID 317''', as well as that crash‘s trace packets with the same value. When enabled, first crash will send eventual record with '''value 1'''. Subsequent crashes will add 1 to value overflowing at 255 and starting again from 0. | Crash Eventual record and Trace records can have a new IO element '''Crash Counter“ (AVL ID 317)'''. In addition to ''Crash Counter, Crash Trace'' must also be enabled in order for the functionality to work. Crash Counter connects the eventual crash record with its trace packets meaning each eventual crash record will have '''ID 317''', as well as that crash‘s trace packets with the same value. When enabled, first crash will send eventual record with '''value 1'''. Subsequent crashes will add 1 to value overflowing at 255 and starting again from 0. | ||
===Ground Vector=== | |||
Ground vector must be removed from the magnitude used in the crash evaluation. Ground vector is calculated when AXL calibration is present, otherwise, it is not removed. Magnitude is recalculated when the device has no calibration. For that, it is supposed, that the required acceleration is on the XY plane. Then angle between the Z axis and the XY plane is 90 deg, therefore Pythagorean theorem can be used. If the magnitude is less than 1 G, the result cannot be evaluated and is set to 0. | Ground vector must be removed from the magnitude used in the crash evaluation. Ground vector is calculated when AXL calibration is present, otherwise, it is not removed. Magnitude is recalculated when the device has no calibration. For that, it is supposed, that the required acceleration is on the XY plane. Then angle between the Z axis and the XY plane is 90 deg, therefore Pythagorean theorem can be used. If the magnitude is less than 1 G, the result cannot be evaluated and is set to 0. | ||
'''Note:''' Each record will have accurate timestamps in milliseconds. | '''Note:''' Each record will have accurate timestamps in milliseconds. | ||
===Crash Classification=== | ===Crash Classification=== | ||