Racelogic VB20SL User manual

VB20SL User Guide
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VB20SL 20Hz GPS Data Logger
With Slip Angle
User Guide

VB20SL User Guide
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Contents
CONTENTS..............................................................................................................................................................................................................................................................................................................................2
INTRODUCTION....................................................................................................................................................................................................................................................................................................................3
FEATURES..............................................................................................................................................................................................................................................................................................................................3
STANDARD INVENTORY ....................................................................................................................................................................................................................................................................................................4
GETTING STARTED .............................................................................................................................................................................................................................................................................................................5
ANTENNA TYPES AND PLACEMENT...............................................................................................................................................................................................................................................................................7
DISPLAY SCREEN.................................................................................................................................................................................................................................................................................................................9
FRONT PANEL CONTROLS..............................................................................................................................................................................................................................................................................................10
SLIP ANGLE OFFSET .........................................................................................................................................................................................................................................................................................................13
PITCH/ROLL ANGLE OFFSET .........................................................................................................................................................................................................................................................................................14
SETTING SLIP ANGLE OFFSET REMOTELY VIA CAN MESSAGES.......................................................................................................................................................................................................................14
LEVEL....................................................................................................................................................................................................................................................................................................................................15
MEMORY CARDS AND LOGGING ..................................................................................................................................................................................................................................................................................15
SMOOTHING AND FILTERING........................................................................................................................................................................................................................................................................................16
DIGITAL AND ANALOGUE OUTPUTS............................................................................................................................................................................................................................................................................17
DIGITAL INPUTS.................................................................................................................................................................................................................................................................................................................17
CAN / RS232 PORTS / USB..................................................................................................................................................................................................................................................................................................18
VB20SL ‘.VBO’ FILE FORMAT .........................................................................................................................................................................................................................................................................................21
VBOXTOOLS SOFTWARE.................................................................................................................................................................................................................................................................................................22
UPGRADING THE FIRMWARE........................................................................................................................................................................................................................................................................................23
SPECIFICATION..................................................................................................................................................................................................................................................................................................................24
CONNECTOR ASSIGNMENTS..........................................................................................................................................................................................................................................................................................26
CAN BUS DATA FORMAT..................................................................................................................................................................................................................................................................................................28
MODULE DIMENSIONS .....................................................................................................................................................................................................................................................................................................29
FUSE RESET BUTTON........................................................................................................................................................................................................................................................................................................29
CONTACT INFORMATION ...............................................................................................................................................................................................................................................................................................30

VB20SL User Guide
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Introduction
The VB20SL is a multi-purpose non-contact speed sensor. Using an advanced dual antenna GPS engine, the VB20SL can calculate not only the speed
and direction of travel of the object upon which it is placed, but also an accurate Slip angle and Pitch or Roll angle. This data is then logged to an inserted
SD card, available on a configurable CAN output and present on a USB or serial output for direct monitoring or data processing by a connected PC running
VBOXTools software.
The VB20SL also features a built-in graphic display allowing the user to set up and configure the unit without using a PC.
The VB20SL is compatible with all of the existing peripherals including the Multifunction display, ADC03, TC8, FIM03, Yaw Rate Sensor and Mini Input
module.
Features
Non-contact 20Hz speed and distance measurement using GPS
Slip Angle and True Heading measurement
Pitch or Roll Angle measurement
1 x CAN Bus interface (on two sockets to allow daisy-chaining)
USB interface for live data, upgrading and SD data transferral
RS-232 serial interface backup for live data and upgrading
SD Card logging
2 x 16bit user configurable analogue outputs (velocity)
2 x Digital outputs (velocity)
Brake trigger input with 210KHz scan rate
Input voltage 6V to 30V operating range
Logging rate selectable from 20Hz, 10Hz, 5Hz, 2Hz, 1Hz

VB20SL User Guide
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Standard Inventory
Description
Qty
Racelogic Part #
VB20SL
1
VB20SL
Mains Charger
1
RLVBACS020
Cigar Lighter adaptor
1
RLVBCAB10
USB Lead
1
RLCAB042
2GB SD Card
1
RLACS083
GPS Ground Plane Antenna
2
RLVBACS103
VBOX Serial PC Cable
1
RLCAB001
CD ROM containing VBOX software
1
RLVBACS030
VBOX Tools Software Manual
1
VBTOOLSMANA5
VBOX 20SL Manual
1
VB20SLMAN
Padded Carrying Case
1
RLVBACS013

VB20SL User Guide
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Getting Started
Required equipment (All supplied as standard unless specified)
VB20SL
Fully charged battery pack or Cigar lighter 12v adapter lead
GPS Antenna
Blank SD card
USB/RS232 Cable
VBOX Software CD
Laptop/PC (not supplied)
1.Install Software
2.Place VBOX in vehicle
3.Fit antenna connector to VBOX
4. Mount GPS antenna on vehicle roof
5.Connect USB or serial cable (CAB01) to laptop
6. Connect other end of USB or serial cable to
VBOX

VB20SL User Guide
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7. Connect the power cable/ battery pack to the
VBOX
8. If using 12v power cable, connect to vehicle
9. See below
9. With the power applied, the Display screen will illuminate. The VB20SL will start searching for satellites. The ST led will indicate the number of satellites
currently in lock. For best results ensure the VBOX has acquired a lock on 5 or more satellites, essential for quality signal reception. When using the VBOX
for the first time or when using the VBOX after a long period of time, allow the VBOX to sit for between 5 and 10 minutes to re-collect data needed to track
satellites.
As the vehicle begins moving, the display will show a file-writing screen then show the normal display screen with the file name of the current file.

VB20SL User Guide
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Antenna Types and Placement
Whilst installation and use of the VB20SL is intended to be fast and simple, careful
attention must be paid to placement of the two antennas.
Note: It is essential that the separation of the two antennas is exactly the same as
the value set in the unit’s configuration screen. If the separation is incorrect, data
may not be given or may be inaccurate. The measured distance between the
antennas should be the straight-line distance between the antennas regardless of
the mounting angle. It is not the 2D distance between the antennas as viewed from
above.
Antenna A is the primary antenna, from which all calculations are based. If overall slip is to be measured
(at the centre of the vehicle), the primary antenna should be placed rearward of the secondary. Alignment
of the antennas is not completely essential as the Slip Angle Sensor has the ability to calculate any offset.
See the Slip Angle Offset Section.
However if you wish to measure Pitch or Roll then the alignment of the antennas must be in line with the
vehicle or at 90o as accurately as possible.
The picture above shows a typical antenna placement for the measurement of Body Slip Angle and Pitch
angle.
The picture to the left shows a typical antenna placement for the measurement of Body Slip Angle and
Roll angle.

VB20SL User Guide
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When measuring slip at a specific point on a vehicle (for example over a given wheel), the primary
antenna must be placed over this point on the vehicle, whilst the secondary antenna should be
placed towards the centre of the vehicle.
GPS antennas require a ground plane to operate correctly. Usually, the metal roof of a vehicle
performs this function. However, if a test requires an antenna to be placed off of the vehicle, then
a special Ground Plane ‘mushroom-style’ antenna must replace the off-vehicle antenna, as these
antennas are capable of operating without a ground plane. The Ground Plane ‘mushroom’ style
antennas RLVBACS065 are available from your VBOX distributor.
If only one antenna will be placed ‘off-vehicle’ then only one Ground Plane antenna need be
purchased.
Antenna Separations >2M
When the antenna separation is >2M it is advised where possible to mount the antennas as level
as possible so that the ‘LEVEL’ option can be enabled, otherwise the RTK lock is not so reliable
and the Slip and Roll/Pitch data can drop out or become intermittent.
The VB20SL must only be used with the supplied antenna, unless instructed otherwise by
Racelogic.
GPS Antenna
The GPS Antennas supplied with the VB20SL are 3.5v active antennas. For the best possible signal
quality, it is important to maintain a clean connection between the antennas and the VBOX. Before
fixing the antennas to the VBOX, ensure that there are no dust particles in either connector.
Replacement antennas are available by contacting your VBOX distributor.
The antenna is a magnetic mounting type for quick and simple mounting to the vehicle roof. For
optimum GPS signal reception, make sure that the antenna is fitted to the highest point of the vehicle
away from any obstructions that may block satellite reception. The GPS antenna works best with a
metal ground plane underneath (eg. Vehicle roof).
Please also note that when using any GPS equipment, a clear sky view is important. Objects in the
surrounding area such as tall buildings or trees can block the GPS signal causing a reduction in the
number of satellites being tracked, or introducing reflected signals that can decrease the accuracy of
the system.
NOTE: VB20SL can struggle with maintaining an RTK lock required for Slip and Pitch
measurement if the antennas are placed too close to Roof Bars. If a poor mounting position
cannot be avoided then use Ground plane antennas, RLVBACS065.

VB20SL User Guide
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Using the VB20SL with one GPS antenna
The VB20SL can be used like a traditional VBOX. Only Antenna A is needed if the VB20SL is to be used like a traditional VBOX without the requirement to
measure Slip, Pitch, YAW rate and Lateral Acceleration channels.
For single antenna use (for standard, non-slip GPS data), the antenna should be connected to the Ant A connector.
Velocity can be output on either the Analogue or Digital outputs.
The VB20SL has a brake trigger input so not only can the VB20SL measure and output Velocity it can measure and output Trigger Velocity, Trigger to zero
Time and Trigger to zero Distance. This data is logged to SD card and available on the CAN bus or USB/serial connection bus along with all the other GPS
data.
NOTE: When measuring a braking distance the GPS optimisation must be set to High, via the Front Panel controls. And
the Velocity Kalman filter set to 0 (zero).
Display Screen
The Display screen will display data when operating it also displays all the menus required to configure the VB20SL via
the front panel controls.
On start-up, the display screen shows the unit’s firmware version and current offset value.
During normal operation, the display screen displays Speed (mph or km/h) and Slip Angle, as well as the number of
satellites that the VB20SL has locked on to. There are also three status displays.
OK (Green):
Indicates that the VB20SL has sufficient satellites locked to allow normal operation.
RTK (Orange):
This flashes to indicate that the VB20SL has locked onto sufficient satellites for single antenna (Speed sensor only) use. The unit will be able to give accurate
data for all channels except Slip Angle, Pitch Angle, True Heading, Lateral Velocity and Yaw Rate.
WAAS/40CM (Orange):
Indicates the DGPS solution that is currently being utilised by the Slip Angle sensor.
SATS (Yellow):
This flashes to indicate that the VB20SL has insufficient satellites and will not be able to operate at all.
Logged File name:
When an SD card is inserted the file name of the logged file appears on the screen whilst data is being logged.

VB20SL User Guide
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Front Panel Controls
The VB20SL can be configured using the front panel buttons, which enables configuration without the need for a computer.
From the main screen, press the’■’ button to enter the configuration screen.
Once in the configuration screen, press the ‘◄’and ‘►’ buttons to highlight the next or previous choice in any menu, and press
’■’ to select the highlighted option. Some menus contain sub-menus, for example the Analogue and Digital Output menus
contain separate menus for each parameter.
Main Menu
SETTINGS
COLDSTART
MODE
SETUP ANTENNAS
SMOOTHING
OUTPUTS
EXIT
Press’■’ to
enter the VBOX
general settings
menu.
Press’■’ to
perform a GPS
cold start
Press’■’ to change the
mode of operation between
VBOX module mode and
Stand Alone mode. Then
press ’■’ to confirm.
Press’■’ to enter the
antenna configurations menu.
This menu contains separate
sub-menus for pitch antenna
and roll antenna pairs
Press’■’ to edit the
smoothing levels of
the Slip, Pitch, Roll,
Lat acc and Long
acc channels.
Press’■’ ’
configure the
digital and
analogue
outputs.
Press’■’ to exit the
setup menu and
cause the settings to
be saved in
EEPROM
Settings Menu
UNITS
USB MODE
LOG OPTIONS
SERIAL RATE
GPS
BACK
Press’■’ to
change the
displayed
Velocity units.
Then press ’■’
to confirm.
KMH or MPH
Press’■’ and
then use the ‘◄’
and ‘►’ buttons
to select whether
the USB port is
assigned to
Serial data mode
or Card reader
mode.
Press’■’ to enter
the Log Options
Menu.
In this menu the
Logging Mode and
Log rate can be set.
Press’■’ and then use
the ‘◄’ and ‘►’ buttons
to select a serial data
rate. The maximum serial
rate is equal to the Log
rate
Press’■’ to enter the GPS
configuration Menu. The
Kalman Filter, Dynamic
Mode and DGPS mode is
configured within this menu.
Press’■’ to go back to
the Main menu.

VB20SL User Guide
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Setup Antennas Menu (Pitch Antennas)
SEPARATION
LEVEL
SWAP
ANTENNAS
SLIP OFFSET
PITCH OFFSET
BACK
Press’■’ and then use the ‘◄’
and ‘►’ buttons to change the
antenna separation. Then press
’■’ to confirm.
Range is 0.0 –5.0M in 0.1M
increments
Press’■’ and then use the ‘◄’ and
‘►’ buttons to enable or disable the
LEVEL option. With the LEVEL set
to YES the RTK lock is more
resilient.
But maximum ROLL or PITCH in
this mode should be 10 degrees.
Set to ‘ON’ to allow the
primary Antenna A to
be mounted ahead of
the Secondary
Antenna B.
Default is ‘OFF’. Then
press ’■’ to confirm.
Press’■’ to enter the
Slip offset sub
menu. Within this
sub menu the Slip
offset can be
calculated and
applied or cleared.
Press’■’ to enter the
Pitch offset sub menu.
Within this sub menu
a Pitch offset can be
calculated and applied
or cleared.
Press’■’ to go
back to the Main
menu.
Smoothing Menu
Lat Acc
Long Acc
Slip
Pitch
Roll
BACK
Press’■’ and then use the
‘◄’ and ‘►’ buttons to
change the amount of
smoothing applied to the
calculated Lateral
Acceleration output. Then
press ’■’ to confirm.
0.0 –5.0 (0.1 steps)
Press’■’and then use the
‘◄’ and ‘►’ buttons to
change the amount of
smoothing applied to the
calculated Longitudinal
Acceleration output. Then
press ’■’ to confirm.
0.0 –5.0 (0.1 steps)
Press’■’ and then use the
‘◄’ and ‘►’ buttons to
change the amount of
smoothing applied to the
Slip angle channel. Then
press ’■’ to confirm.
0.0 –5.0 (0.1 steps)
Press’■’ and then use
the ‘◄’ and ‘►’ buttons
to change the amount of
smoothing applied to the
Pitch angle channel. Then
press ’■’ to confirm.
0.0 –5.0 (0.1 steps)
Press’■’ and then use the
‘◄’ and ‘►’ buttons to
change the amount of
smoothing applied to the
Roll angle channel. Then
press ’■’ to confirm.
0.0 –5.0 (0.1 steps)
Press’■’ to go back
to the Main menu.

VB20SL User Guide
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OUTPUTS: Digital Setup Menu (Channel 1 and 2)
OUTPUT
PULSES PER
METER
MAX VELOCITY
MAX VALUE
MAX FREQUENCY
TEST
EXIT
Only available when output
is set to Velocity
Only available when output
is set to Velocity
Only available when output
is set to Pitch or Slip
Only available when output
is set to Pitch or Slip
Press’■’ and then
use the ‘◄’ and
‘►’ buttons to
associate either of
the following
channels Velocity,
Slip, Pitch, Lat
Acc and Long Acc
to the Digital
output. Then
press ’■’ to
confirm.
Press’■’ and then use the
‘◄’ and ‘►’ buttons to
set the number of pulses
per revolution. Then press
’■’ to confirm.
0.1 –120 (0.1 Steps)
Press’■’ and then use the
‘◄’ and ‘►’ buttons to
set the maximum Velocity.
Then press ’■’ to confirm.
10-400Km/h (1km/h steps)
Press’■’ and then use the
‘◄’ and ‘►’ buttons to
set the maximum value of
that channel. Then press
’■’ to confirm.
10- 400o (1osteps)
Press’■’ and then use the
‘◄’ and ‘►’ buttons to set
the maximum Frequency
used on the digital output.
Then press ’■’ to confirm.
1-50Khz (0.1Khz steps)
Press’■’ and
then use the
‘◄’ and ‘►’
buttons to set a
test value that
the Digital
output will
simulate. Then
press ’■’ to
quit.
Press’■’ to
exit the
setup menu
and cause
the settings
to be saved
in EEPROM
OUTPUTS: Analogue Setup Menu (Channel 1 and 2)
OUTPUT
VALUE @ +5V
VALUE @ 0V
VALUE @ -5V
TEST
EXIT
Only available when output is
set to Velocity
Only available when output is
set to Pitch or Slip
Press’■’ and then use the
‘◄’ and ‘►’ buttons to
associate either of the
following channels
Velocity, Slip, Pitch, Lat
Acc and Long Acc to the
Analogue output. Then
press ’■’ to confirm.
Press’■’ and then use the
‘◄’ and ‘►’ buttons to set
the value to represent +5V.
Then press ’■’ to confirm.
0-400kmh or –360o to 360o
(1km/h or 0.1osteps)
Press’■’ and then use the
‘◄’ and ‘►’ buttons to set
the velocity to represent 0V.
Then press ’■’ to confirm.
0-400kmh (1km/h steps)
Press’■’ and then use the ‘◄’
and ‘►’ buttons to set the
value to represent -5V. Then
press ’■’ to confirm.
–360o to 360o(0.1osteps)
Press’■’ and then use the
‘◄’ and ‘►’ buttons to set
a test value that the Digital
output will simulate. Then
press ’■’ to quit.
Press’■’ to exit
the setup menu
and cause the
settings to be
saved in
EEPROM

VB20SL User Guide
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Slip Angle Offset
When using the VB20SL for measurement of Slip Angle, Pitch / Roll Angle, True Heading, Lateral Velocity or Yaw Rate, it is essential that the Slip Angle
offset is determined before conducting tests. This then compensates for any misalignment in the placement of the two antennas.
There are also many occasions when the antennas cannot be placed directly in line with the car, such as when an ‘off-vehicle’ antenna is used to measure
the Slip angle over a particular wheel.
Measuring Roll angle and Slip Angle
To measure Roll angle at the same time as slip angle will require the antennas to be mounted at 90 degrees to the body of the car, in this case it is vital that
the offset is calculated.
Setting the Offset
The VB20SL includes a built-in facility for calculating and setting the offset. With the antennas placed suitably and the antenna separation set correctly in the
unit, enter the Configuration Screen and select ‘Calc. Offset’. The unit will give instructions on its display screen to allow it to determine the offset.
First, the unit will instruct you to drive at a speed greater than 25km/h. Once this is achieved, the unit will tell you to drive straight,
and will begin calculating the Slip Angle offset automatically. During the 5 second process, it is very important that you keep the
vehicle in a straight line and above 25km/h. The Slip angle sensor beeps during this calculation and then stops beeping when it
has finished calculating the offset.
If required, the Slip Angle offset can be re-calculated at any time by repeating this procedure. Selecting the ‘Clear Offset’ option in the Configuration Screen
will clear the current offset value.
Please note that the unit will need to have a full RTK lock to perform this procedure –if the orange ‘RTK’ light is flashing, the procedure cannot be initiated.

VB20SL User Guide
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Pitch/Roll Angle Offset
It is not always possible to mount the antennas on a vehicle so that they are perfectly level. In order to compensate for a non-level antenna placement you
should use the Pitch offset facility, which will automatically compute and then use an offset compensation.
Measuring Roll angle:
To measure Roll angle accurately the antennas need to be aligned as close as possible to a line perpendicular 90oto the longitudinal line of the car.
Setting the Offset
Press the ’■’ button to enter the Main menu then select the Setup Antenna Menu, and then select the Pitch antenna setup menu.
From within either the Pitch antenna setup menu select Pitch Roll offset, when the screen shows ‘CALC OFFSET’ press the ’■’ to calculate the PITCH offset.
If required, the Pitch Angle offset can be re-calculated at any time by repeating this procedure. Selecting the ‘Clear Offset’ option will also clear the current
offset value.
Setting Slip Angle Offset Remotely via CAN Messages
It is possible to request that the VB20SL calculates a Slip Angle Offset by sending it requests via CAN.
The CAN Baud rate is 500Kbit/s, Motorola 11 bit –Standard Frame, The DLC = 8
The VB20SL will respond on CAN to indicate stages of the Slip offset process and also indicate completion or failure.
Please see the table below:
Message Type
CAN ID
Data Bytes
0
1
2
3
4
5
6
7
Request
Start Slip offset calculation
0x7FE
46
49
4C
45
4D
41
4E
40
Request
Cancel Slip offset calculation
0x7FE
46
49
4C
45
4D
41
4E
41
Response
Increase speed to >25kmh
0x7FB
05
02
00
00
00
00
00
00
Response
Drive Straight
0x7FB
05
03
00
00
00
00
00
00
Response
Offset done –value shown in Data bytes 2-5
0x7FB
05
01
3F
9D
70
A4
00
00
Response
Offset failed
0x7FB
05
00
00
00
00
00
00
00
The Response message to indicate completion also contains the Offset value as a 32 bit IEEE float on Data bytes 2-5.
In the example above Data bytes 2 - 5 = 3F 9D 70 A4 which equals a decimal value of 1.23o

VB20SL User Guide
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Level
The ‘LEVEL’ option should be enabled (set to YES) when the antennas are mounted within 10oof each other and the expected Pitch/Roll measurement will
not exceed 10o. With the LEVEL option enabled the GPS engines maintains its RTK lock more efficiently and the Slip and Pitch channels are less likely to
drop out.
If the expected Pitch or Roll angles will be greater than 10othen the ‘LEVEL’ option should be disabled (set to ‘NO’).
Note: when the antenna separation is <2M the RTK lock is very resilient in most conditions and scenarios when the ‘Level’ option is not enabled.
Memory Cards and Logging
The VB20SL stores logged data onto SD Cards. The supplied SD cards are already optimised for use on the VB20SL and as such do not need formatting
before use. Should the SD Card need formatting due to card errors it should only be formatted using the ‘Format Compact Flash’ option in the VBOXTools
software. The SD Card will need to be inserted into an SD Card reader (or a VB20SL set to ‘Card Reader’ USB Mode) for this to work.
When logging data to an SD Card the OLED display will show the name of the current file at the bottom of the display. It is important not to remove the SD
Card while the VB20SL is logging. If the card is removed while the VBOX is writing data to it, there is a risk that the data file may be corrupted resulting in loss
of data. If ‘Log only when moving’ is the logging mode selected then wait a short time after the vehicle has stopped for logging to finish and the filename to
disappear from the screen. If ‘Log continuously’ is selected, press the Start/stop logging switch if connected or press ’■’ on the front panel. This will enter
the on-board configuration screen and close the file so that the card can be removed.
It is recommended that files are removed from the disk regularly as writing continuously with out fragments is easy. The more file fragments the
harder it is to stream data to the card.
There are two Logging modes:
‘Log only when moving’ : In this mode the VBOX will start to log data only when a speed higher than 0.5km/h is detected.
‘Log continuously’: Data is continuously logged to the SD card regardless of vehicle velocity or the number of satellites.
To set channels to be logged, they must be selected in the VBOX setup window of VBOXTools, see the VBOXTools manual for further information.
Maximum Log channels without Kalman Filter enabled = All standard channels plus 20 input channels
Maximum Log channels with Kalman Filter enabled = All standard channels plus 10 input channels

VB20SL User Guide
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Smoothing and Filtering
Velocity: The VB20Sl has three smoothing settings (Dynamic Modes) for velocity, High Dynamics, Normal and Low Dynamics. High dynamics has the least
amount of smoothing and must be used for high dynamic tests where Time or Distance measurements are critical to the test, such as Brake stop and
acceleration tests.
Slip, Pitch Angle and Acceleration channels: The smoothing routine is set by selecting a value from 0 –5.0 in 0.1 steps. This value corresponds the size in
time (S) of a moving window smoothing routine.
e.g. if 0.3 is selected then a smoothing window of 0.3 seconds (6 samples @20Hz) will be applied to the data.
Kalman Filter:
This filter provides filtering separately to the Velocity and Position channels (long, lat and height). Note with any live filter routine more latency will occur if
higher levels of filtering are used. Hence the Kalman filter velocity settings should be set to zero for Brake stops and acceleration runs.
It is often better to record un-filtered data then use software filter routines after if necessary as these will have much less impact on latency.

VB20SL User Guide
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Digital and Analogue Outputs
The digital outputs on connectors OUT1 and OUT2 are a frequency/pulse output corresponding to velocity. The pulse per meter range is adjustable in
software or via the front panel controls.
The analogue outputs on connectors OUT1 and OUT2 output 0-5volt DC signal corresponding to velocity. The velocity per volts range is adjustable in
software or via the front panel controls.

VB20SL User Guide
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Digital Inputs
The DIGITAL I/O socket contains the two digital inputs for the VB20SL. Digital input 1 is also referred to as the Brake trigger input. This input is connected to
an internal timer capture module that is able to record precisely an event time for use in brake distance calculation. This period of time is called the trigger
event time, and is logged as the value in milliseconds between the trigger event and the last GPS sample.
A hand-held brake trigger is also available to allow the user to record marker events in the VB20SL data file.
A remote logging on/off switch is also available for ease of use and when the front panel switch is not accessible.

VB20SL User Guide
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CAN / RS232 Ports / USB
The VB20SL is equipped with a CAN Bus interface, a RS232 serial port and an USB port. The RS232 port or USB is used for all communication between the
VBOX and laptop PC. The USB or RS232 ports are able to transmit live data from the VBOX to the PC for viewing and performing real-time tests.
Note only the USB port is used for firmware upgrading
The CAN Bus port is available in either the socket labelled CAN or the socket labelled Serial. This CAN port has two functions known as Internal and External
mode.
Internal Mode:
This mode should be selected when Racelogic input modules are connected to the VBOX. In this mode the CAN id’s and Baud rate are non configurable.
External Mode:
This CAN mode should be used when a VBOX CAN data output is to be used by an external CAN device such as a Data acquisition system. In this mode the
attributes of the CAN output stream are configurable by the user.
See the section ‘Setup’ in the VBOX software manual.
The Socket labelled CAN also contains a secondary RS232 port for direct connections to the GPS engine for Local DGPS correction connection.

VB20SL User Guide
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Using the USB cable
The first time you use the USB cable, you may need to follow the instructions below.
Connect the USB cable between the VB20SL and your computer.
Your computer will now recognise the presence of a new device, after a period of time a
‘Found New Hardware Wizard’ window will appear. See below.
Click the option ‘No, not this time’ and click ‘Next’ (see image, right)
A new window will appear at this window click ‘Next’ (see image, below)
A new ‘Hardware Installation’ window will appear. Click the button labelled ‘Continue
Anyway’.
At the last window click ‘Finish’ to complete the installation.
After a short period of time a window will ask you if you wish to reboot your computer, select
‘NO’
Now disconnect the power from the VB20SL and then reconnect the power, your computer will now
recognise the Slip angle sensor. When you run the VBOXTools software it will recognise the USB
connections