UEI RackTangle Output Verification

OVMS Quiet/Short Testing

OVMS General Information

Requirements

• OVM system requirements (1 December 2008; Hinz, Connors, Kraus): OVM-requirementsv3.pdf

Test Reports

• UEI RackTangle Test (Borelli, Brix, Bertram; v12): UEI-Performancetests_V12.pdf

Installation

• OVMS SX M2 Accelerometer installation notes (Tom Connors, LBTI): M2_Accelerometer_Installation_ver1.pdf

• Requested OVMS electronics location: RackSpaceMemo(OVM).pdf

Proposed locations of OVMS accelerometers (as of 2 December, 2009)

Location	Quantity	Comment	Status
SX M1	5	3 OPD, 2 lateral	Not installed
DX M1	5	3 OPD, 2 lateral	Not installed
SX M2	5	3 OPD, 2 lateral	Installed
DX M2	5	3 OPD, 2 lateral	Installed
SX M3	5	3 normal to mirror, 1 parallel to plane of mirror, 1 parallel to ground plane (at zenith)	Installed
DX M3	5	3 normal to mirror, 1 parallel to plane of mirror, 1 parallel to ground plane (at zenith)	Installed
L-N Rails	6	total for L-N	not installed
LBTI Rails	6	total for LBTI	not installed
"floaters"	3		not installed
Total	45

-- JorgeEsguerra - 18 Aug 2010

M3 Accelerometer installation locations (pictures)

• OVMS_M3_Accelerometer_Pictures.ppt: Pictures of installed M3 accelerometers

-- JorgeEsguerra - 18 Aug 2010

Pre-OVMS Commissioning Data Sets

• 4 April, 2010 OVMS Data

-- JorgeEsguerra - 10 May 2010

• NOTE: Data collected with the OVMS RackTangle between September 2009 and January 2010 is affected by timing issues. The scan rate discrepancy impacts analysis results slightly. See here: UEI RackTangle + AI-211 Scan Rate Discrepancy

-- JorgeEsguerra - 03 Feb 2010

• 9 October, 2009 OVMS data

• 26 October, 2009 OVMS data

• 27 October, 2009 OVMS data

-- JorgeEsguerra - 30 Nov 2009

OVMS Hardware

Computing / DAQ

• dnr-12-1g_manual.pdf: UEI RackTangle manual

• dnr-12-1g.pdf: UEI RackTangle datasheet

A/D Gain selection

* Obtain the gain you want by fiddling with the max/min expected measured values

* Creating an accelerometer seesion automaticall sets the gain based on expected measurement magnitude

* You can "set" the gain by specifying expected measurement values using this Voltage / accleration / gain table

-- JorgeEsguerra - 04 Feb 2010

OVMS Accelerometer Data

• PCB 393B05 scal factors and serial numbers

-- JorgeEsguerra - 02 Feb 2010

UEI RackTangle + AI-211 Scan Rate Discrepancy

• Discovered January, 2010. Affects LBT data collected between Sept 2010 and January 2010.

• Analysis of data collected with the OVMS UEI RackTangle indicates that there are discrepencies between the user-specified scan rate and the actual scan rate. UEI has reponded that this is normal behavior.

• The discrepancy was observed when using clock triggering off of the 24-MHz and 66-MHz clocks. Based on user specified scan-rate, the software/firmware selects a scan-rate that is close to the user specified rate.

• The user is then responsible for verifying the actual scan-rate that data is collected at by reading the scan-rate output or calling the appropriate libraty functions to write/display the scan rate.

• An on-board PLL can be configured (software) to provide triggering as well. However, it was observed that the scan-rate displayed using the LabView library is incorrect, displaying user specified desired scan-rate and not the actual scan rate.

• Below is a list of scan-rates for LabView operation of the UEI RackTangle with AI-211 devices installed, and triggering from the on-board 24 and 66-MHz clocks:

User specified scan rate (Hz)	Scan rate reported by LabView (Hz)	Scan rate confirmed through (FFT) analysis
64	64.45	no
128	128.906	no
200	201.416	no
256	257.812	no
300	300.481	no
400	402.832	no
500	503.54	no
512	515.625	no
600	600.962	no
700	700.577	no
800	805.664	no
900	901.442	no
1000	1007.08	yes
1024	1031.25	no
2000	2014.16	no
2048	2062.5	no
2500	2503.03	no
3000	3024.19	no
3500	3531.68	no
4000	4028.32	no
4096	4125	no
4500	4523.03	no
5000	5006.07	no

• ScanRates.xls: Scan-rate list in MS Excel format

-- JorgeEsguerra - 02 Feb 2010

• Below is a list of scan-rates for LabView operation of the UEI RackTangle with AI-211 devices installed, and triggering from the on-board PLL:

User specified scan rate (Hz)	Scan rate reported by LabView (Hz)	Scan rate confirmed through (FFT) analysis
1000	1000 (wrong)	982-Hz (estimated)
1018	1017.99 (wrong)	1000-Hz (estimated)

1000-Hz UEI data acquisition scan rate correction:

• 1000-Hz UEI data acquisition scan rate correction. (Uncluttered):
  

• Example of scan rate error: Analysis of 300-Hz sine:
  

• Example of scan rate error: Analysis of 300-Hz sine (zoomed):
  

200-Hz UEI data acquisition scan rate correction. (Uncluttered):

-- JorgeEsguerra - 10 Feb 2010