Home > VBOX Automotive > VBOX data loggers > VBOX 3i Range > VBOX 3i User Manual (All Variants) > 12-2 - VB3i IMU Integration - Roof Mount

12-2 - VB3i IMU Integration - Roof Mount

When using the IMU roof mount, the user has the option to translate the data from the roof to another point on the vehicle. By default, when the roof mount is enabled, a 1 m Z offset is added, translating the filtered speed down in to the vehicle, towards the centre of gravity.

 

If the Kalman Filter data is required relative to an alternate or more precise location on the vehicle, then measurements should be made from the centre of the IMU to the desired location. As the IMU is housed within the enclosure, precise measurements are not easy to make. So a Z measurement can be taken from the centre of the GPS antenna, provided 3 cm is subtracted from the physical measurement. Translation measurements need to be made in all 3 axis, X, Y and Z.

Required equipment

IMU04
VB3i (IMU04 ready)
IMU04
VBOX Tools or VBOX Setup
RLCAB119 VBOX – IMU connecting cable
RLCAB001 / RLCAB066-2 – VB3i PC connection cable
VBOX Manager (optional)

Setup

Hardware

Important note: IMU04 must be connected to VB3i before power is applied to ensure data is correctly synchronised.

  1. Fit the VBOX 3i into the test vehicle, and mount the IMU roof mount on the vehicle roof.
  2. Connect antenna from IMU roof mount to the primary antenna of the VB3i (antenna A).
  3. Connect RLCAB119 cable from left hand port on roof mount IMU (CAN/KF) to VBOX 3i-V3/V4 25W D analogue input port.
  4. Take data translation measurements in X, Y and Z axis from centre of IMU, if required. Default 1 m under IMU.
  5. After IMU is connected, apply power to VBOX 3i.
  6. Enable IMU integration using VBOX Manager, VBOX Tools - VBOX Setup or VBOX Setup.
     
VBOX 3i-V3/V4 and IMU04

11.png

VBOX Tools

  1. Ensure IMU04 is connected via RLCAB119, and the VBOX 3i is powered on.
  2. Connect VBOX 3i to PC using RLCAB001 or RLCAB066-2 cable (RS232 or USB).
  3. Open VBOX Tools and connect to VBOX 3i by selecting COM Port (Options from Toolbar).
  4. Run VBOX Setup.
  5. Ensure 'High Dynamics' GPS Optimisation is selected, and log rate is set to 100 Hz (Logging tab).
  6. Tick 'Use IMU' box. Once VBOX Tools has completed the initial enabling, tick the 'Roof mount' box.


     
  7. Enter the distances measured from IMU to required translation point.
  8. The IMU Attitude channels (Head_imu, Pitch_imu and Roll_imu) will automatically be set to log. If IMU Attitude data is required to be displayed as a Live Serial data display then the user must tick the channels for Send over serial.

    1.png
     
  9. Perform initialisation and full calibration procedure before commencing testing.

VBOX Setup

  1. Ensure IMU04 is connected via RLCAB119, and the VBOX 3i is powered on.
  2. Connect VBOX 3i to PC using RLCAB001 or RLCAB066-2 cable (RS232 or USB).
  3. Open VBOX Setup and connect to VBOX 3i by selecting COM Port.
  4. Select the 'GPS' menu and the 'Settings' tab, ensure that 'GPS Optimisation' is set to 'High dynamics'.
  5. Select the 'Logging' menu and ensure that 'Log rate' is set to '100 Hz'.
  6. Select the 'IMU' menu and tick 'Enable IMU kalman filter'. Once VBOX Setup has completed the initial enabling, tick the 'Roof mount' box.


     
  7. Enter the distances measured from IMU to required translation point.
  8. The Internal IMU Attitude channels (Head_imu, Pitch_imu and Roll_imu) will automatically be set to log. If IMU Attitude data is required to be displayed as a Live Serial data display then the user must tick the channels for 'Send over serial'.


     
  9. Select 'Write to unit' to upload settings to VB3i.
  10. Perform initialisation and full calibration procedure before commencing testing.

VBOX Manager

  1. Ensure IMU04 is connected via RLCAB119, and the VBOX 3i is powered on.
  2. Enter SETUP, select 'IMU-INS' then click on 'ENABLE ROOF MNT'. 
111.png

  1. Once OK confirmation screen has cleared, ENABLE IMU and ENABLE ROOF MNT should be ticked.

 
  1. Apply IMU TRANSLATION using IMU to translation point measurement distances.
444.png  
  1. IMU Attitude and 3 Axis Modules channels will be automatically set to log. If IMU Attitude or 3 Axis data is required to be displayed as a Live Serial data display (with VBOX Tools) then the user must enter VBOX Setup and tick the channels for 'Send over serial'.
  2. Perform initialisation and full calibration procedure before commencing testing.
  3. If the IMU is not mounted on a flat surface, perform ANGLE OFFSETS calibration. This will zero the Pitch_imu and Roll_imu channels. Calibration must be performed after the calibration has been completed, and the vehicle is static on a level surface.

777.png
  1. If ADAS testing is being conducted, select 'ADAS Mode' from the menu. This option changes the rate at which the kalman filter takes a GPS positional sample to improve the positional performance of the filter. Whilst this is beneficial to ADAS testing, it slightly decreases the accuracy of the filtered speed and therefore shouldn't be selected when undertaking speed based testing such as brake stops.

  1. Once OK confirmation screen has cleared, ADAS Mode should be ticked.

Important notes

  1. To use IMU04 integration, a VB3i-V3 or V4 must be used. This is an IMU04 enabled VBOX 3i unit.
  2. IMU04 cannot be used with IMU integration if it is connected to a VBOX via CAN (RLCAB120 / RLCAB005-CS). This method of connection will only allow standard IMU channels to be logged. See using IMU as CAN module section for details.
  3. The IMU04 standard channels can also be logged when the IMU04 is connected via KF port with cable RLCAB119, without enabling IMU integration
  4. The IMU04 must be in a Racelogic CAN mode to be used for IMU Kalman Filter.
  5. NB ADAS - If using IMU filter with ADAS mode, the GPS antenna and IMU must be co-located (roof mount) or positioned so there is no relative X or Y offset between them. If there is a difference, manual contact points should reference the IMU location, rather than the GPS antenna.
  6. NB ADAS - When using IMU Filter the user cannot use SET POINTS functionality to define contact points in single or multi target ADAS modes

Initialisation

When using IMU integration, an initialisation phase is required when the IMU is first connected to the VBOX after being set up. This will be run through automatically after the VBOX has successfully gained satellite lock. When the IMU LED on VB3i front panel has turned a flashing green, the initialisation is complete.

Note: If you are using a VB3i-V1, which has no IMU LED, read the LED indicators section below for LED behaviour. 

LED Indicators VBOX 3i (V2/V3/V4) and IMU04

  Colour
VBOX 3i LED Solid Orange Flashing Orange Flashing Green Solid Green
IMU IMU enabled, no IMU connected. SAT lock OK. 30 second stationary initialisation in progress. If vehicle moves, LED will continue to flash until 30 seconds stationary completed. Initialisation complete – movement not yet detected. Movement detected – IMU integration working OK.
  Colour
IMU04 LED Red Orange Green
Power Initial boot up phase Temperature checks. If temperature outside optimum operation range, LED will remain orange. Fully operational.
Coms No coms Using IMU integration, inertial data being sent to host VBOX via RS232. Inertial data being sent to host system via CAN.
You must to post a comment.
Last modified
15:36, 18 Jul 2017

Tags

This page has no custom tags.

Classifications

This page has no classifications.
Having trouble finding what you need?