MoTeC ACL VIM - Manual (Page 23)

MoTeC Operation 19
Real Time Value (For devices other than VIM, ADL2, SDL)
The real time value from other devices and from internal calculations is
not anti-aliased at the logging rate, however the value can be anti-
aliased in the logging.
Phase Shift
The anti-alias filter will cause a phase shift (time delay) of half the
logging rate. For example, a channel logged at 100 Hz is logged every
10 milliseconds, so it is delayed by 5 milliseconds.
For most purposes this time delay is not an issue.
Channels logged at the same rate are delayed by the same amount,
which negates this effect when comparing these channels.
This applies to all channels whether they are generated internally from
a calculation or whether they are generated externally from devices
such as a VIM or a display device.
Retrieving the Logged Data
A PC is used to unload the logged data from the ACL. The logged data is then
stored on the computer’s hard disk.
The logged data may be retrieved at very high speed using the Ethernet
connection. After each unload, the user has the option to clear the ACL
logging memory.
The unload may be interrupted part way through if necessary by
disconnecting the computer. The partial unload will contain the most recently
logged data and will be stored on the computer’s hard disk. In this case the
ACL logging memory is not cleared and logging will continue as normal at the
end of the existing data. Next time the logged data is unloaded both the new
data and the previously partly unloaded data will be retrieved.
Track Map Sensor Requirements
In order for the logging analysis software to plot a track map the following
sensors are required and must be logged.
• BR2 Beacon Receiver (Note that the ‘Beacon’ Channel must be logged)
• Lateral G force
• Wheel
Speed
• Longitudinal G force (Optional: See Below)