The vibration total value (PVTV: Point Vibration Total Value and OVTV: Overall Vibration Total Value) of weighted acceleration, determined from the vibration co-ordinate can be calculated using RIDE_INDEX function that is implemented in the Adams Car Ride plug-in. This function is part of the Adams expression builder and listed under the miscellaneous category. The use cases and calling syntax is listed below.
The first three real arrays list frequency weighted acceleration RMS values at three different locations (feet, seat and back rest) in three different directions X, Y and Z respectively. The data passed to these functions must be in MKS units. The first component of every first three array is weighted acceleration vector sum of signal. The next three components are simply frequency weighted RMS acceleration values in three orthogonal directions X, Y and Z. The array size of these first three real arrays should be four. You can directly use the return array of function RIDE_WARMS as input for these first three arrays. The fourth real array should be of size twelve and lists multiplying factors kx, ky and kz as suggested in ISO document for every location in the sequence feet, seat, back-rest and for OVTV respectively. The last string array should be of size greater than one. The RIDE_INDEX function is smart enough to return the real array of same size of this last array. The components of this last string array are listed here and you can pass them in any order you like:
MAX_WARMS: Returns maximum component value out of the first three arrays
MIN_WARMS: Returns minimum component value out of the first three arrays
PVTV_FEET: Returns vibration total value of weighted RMS acceleration at the feet location
PVTV_SEAT: Returns vibration total value of weighted RMS acceleration at the seat location
PVTV_BACK: Returns vibration total value of weighted RMS acceleration at the seat back location
OVTV: Returns overall vibration total value
Format
RIDE_INDEX (ARRAY, ARRAY, ARRAY, ARRAY, ARRAY)
Array | Array of size four with frequency weighted acceleration RMS values in Resultant, X, Y and Z directions at feet.
You can pass return array of RIDE_WARMS. |
Array | Array of size four with frequency weighted acceleration RMS values in Resultant, X, Y and Z directions at seat.
You can pass return array of RIDE_WARMS. |
Array | Array of size four with frequency weighted acceleration RMS values in Resultant, X, Y and Z directions at back-rest. You can pass return array of RIDE_WARMS. |
Array | Array should be of size twelve and it lists multiplying factors kx, ky and kz as suggested in ISO document for every location in the sequence feet, seat, back-rest and for OVTV respectively. |
Array | Array of character should be of size greater than one. The RIDE_INDEX function is smart enough to return the real array of same size of this last array. |
Examples
RIDE_INDEX( RIDE_WARMS(
CREATE_ARRAY(0.0,0.125,1.0),
UNITA(9),
COSA(CREATE_ARRAY(0.0,45.0,360.0),1.0),
SINA(CREATE_ARRAY(0.0,45.0,360.0),1.0),
{"TIME","Wu","Wu","Wu"}),
RIDE_WARMS(
CREATE_ARRAY(0.0,0.125,1.0),
UNITA(9),
COSA(CREATE_ARRAY(0.0,45.0,360.0),1.0),
SINA(CREATE_ARRAY(0.0,45.0,360.0),1.0),
{"TIME","Wd","Wd","Wk"}),
RIDE_WARMS(
CREATE_ARRAY(0.0,0.125,1.0),
UNITA(9),
COSA(CREATE_ARRAY(0.0,45.0,360.0),1.0),
SINA(CREATE_ARRAY(0.0,45.0,360.0),1.0),
{"TIME","Wc","Wu","Wu"}),
{1.0, 1.0, 1.0,
1.4, 1.4, 1.0,
1.0, 1.0, 1.0,
1.0, 1.0, 1.0},
{"PVTV_BACK","PVTV_SEAT","PVTV_FEET","MAX_WARMS","MIN_WARMS"}
)
This function builder function will return array {1.55, 1.77, 2.14, 2.14, 0.76}. It means, PVTV_BACK = 1.55, PVTV_SEAT = 1.77, PVTV_FEET = 2.14, MAX_WARMS = 2.14 and MIN_WARMS = 0.76.