Coding for Load Cell Walls (LCW)

[DiVe]

Hello colleagues,

I am looking for the proposal we have ones discussed for a unique coding of Load Cell Walls. My latest document is dated Feb. 2003 and I feel that this does not reflect the final decision we have made.
There must be also some sketch of the geometry as a example.
Could anyone provide the most recent document for this coding proposal please.

Thanks and bye
Dirk

[Paul Wellicome]

If I recall correctly, from our meeting in Schwieberdingen (late 2003 or early 2004?), we had decided to give the loadcells codes where FL1, FL2 were positions X and Y from the origin, which was the top left corner. B 0 FBAR RR CC 00 FO ? ? would be the generalized code, where RR is the row number and CC is the column number.

I aslo recall discussing RR and CC as percentages across / down the loadcell wall. This was to accomodate the Volvo loadcell wall which has loadcells of different sizes around the four edges - so you cannot simply give a row and column number to locate the loadcell. I'm not sure that we decided to adopt this.

There were other problems too - in allowing up to 99 rows and 99 columns, we're allowing 9801 channels. Under V1.*, this would not fit easily in the CHANNELS folder with an 8.3 filename format. Also, if the loadcell is three-axis, we'd need to increase that potentially to 29403 channels. V2, with multichannel files, would reduce that number, of course, and would be a sensible thing to do.

There would be the possibility of using a BARRIER subfolder, with associated Barrier Information File. There are some data that are needed here - Barrier Mass, Yaw angle, refernece system, origin co-ordinates, number of loadcells, to name but a few - and the individual channel file headers would need some additional attributes - width, height, loadcell top left X and Y, as examples.

Perhaps we can discuss this at MIRA next week!

[Paul Wellicome]

and why the suggestion was for FBAR and not LOMA, I'm not too sure. Also, if the loadcell matrix were on a mobile barrier, presumably the code would use M 0 MBAR...

[DiVe]

The latest coding approach could be found in RED A from version 1.4 , section 2.2.5:

Test channel files - Hint: Barrier load cell channel code
For barrier load cells the channel code has to be M?LOMA??nnmm???? for mobile and B?LOMA??nnmm???? for
fixed barriers, where nn gives the row in percent of the total height and mm gives the column in percent of the total
width of the load cell matrix. The values nn and mm are the positions of the load cell center rounded to the nearest
integer. The barrier is seen as a vehicle with a coordinate system according to SAE J211/1 MAR95 Instrumentation
for Impact Test. This means the row points into the Y-, the column into the Z-direction and the origin is in the left
upper corner of the load cell matrix looking from the barrier to the other test object.

see also:
A.2.2.7 Channel file – Additional descriptors for load cells
To describe load cell geometry

Item closed.