Class-8 Heavy Truck Duty Cycle Project Final Report - Center for ...

the secondary as the static IP necessary for communication with the
eDAQ, as outlined below.
1) Go to Start > My Computer > My Network Places > View
Network Connections
2) Double-click on Local Area Connection.
3) Under the General Tab, scroll down, select Internet Protocol
(TCP/IP), and click Properties.
4) Under the General tab, select Obtain an IP address
automatically
5) Under the Alternate Configuration tab, select User configured
IP address: 192.168.100.xxx (or required IP)
Subnet mask: 255.255.255.0 (or required Subnet
mask)
6) Click OK, Close, and close Network Connections.
Note: Because the static IP address is the alternate, the computer will
usually take a few minutes to recognize the eDAQ.
Timing Issue
The time stamping done by the eDAQ is based on the internal starting
time and the frequency with which samples are being taken.
Therefore, over a test period of several days, the clock will usually drift.
To resolve the time issue, the following precautions were taken.
1) The VBOX will record UTC (in seconds) as a regular data point;
this time will be used to check the time stamp. UTC is basically
Greenwich Mean Time; this time will have to be adjusted to the time
zone in which the data is taken (including Daylight Savings Time) in
order to determine time of day (rush hour, night, etc.)
2) Every time data is uploaded from the eDAQ, the eDAQ time
(used for time stamping) will be readjusted to the computer time.
3) In order to avoid confusion, the eDAQ internal clock needs to be
kept in one time zone and not changed for Daylight Savings Time.
For simplicity (and since the time will need to be adjusted anyway
based on season and zone), the computer is set to GMT and the
eDAQ will be synchronized with that (eDAQ on UTC also).
Procedures for setting the appropriate time zones appear in
Section 9.1.4.
Antennas and GPS coordinates
When the VBOX takes data in stand-alone data acquisition, it saves
the coordinates in degrees. When the VBOX sends CAN data to the
eDAQ, it sends the coordinates in degrees and minutes; a series of
computed channels have been set up to convert the coordinates from
the VBOX into degrees (Section 7.2.5.C.) The GPS coordinate data
taken directly by the eDAQ’s antenna are in degrees. However, when
the eDAQ’s GPS antenna is used, the data is updated at 1 Hz.
Therefore, if the sampling rate of the eDAQ is set to 5 Hz, the data will
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