Brake Test - Brake Trigger

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This page contains an overview of the Test Setup in the Brake Trigger Plugin.

The Brake Trigger plugin for VBOX Test Suite gives you the ability to complete brake tests and compare and analyse the brake stops from a user-defined start speed.

Ribbon - Test Setup

The Brake Trigger plugin has a unique Test Setup ribbon, from which you can configure the test.

Test Section

Configure

Report

Maths Channel

Save Settings

Click on the Save Settings button to save the current test setup and add it to the Saved Settings area in the Add Test window.

The test will also be added to the list under the Brake button in the Test section of the Home tab for easy access.

Export

Gate Section

Add Gate

Click on the Add Gate button to add a virtual gate to the chart and map at the point of the cursor. Gates are indicated by green lines. The currently selected gate will be indicated by a blue line.

You can now use the gates to define start and/or end conditions.

Note: Opening a plugin (either as a new tab or overwriting an existing one) will clear all set gates, requiring you to redefine the gates before you amend the test configuration to set start/end conditions.

Gate Name

Width

Rename

Delete

Delete All

Export

Import

Data Column Section

Add

Channel

Result Condition

Sort Ascending

Sort Descending

Run Section

Select All

Deselect All

Session Section

Edit Data

Vehicle

Vehicle Model
Vehicle Number
Driver Name
Transmission
Engine Size
Power

Brakes

Front
- Brake
- Disc/Drum
- Pads
Rear
- Brake
- Disc/Drum
- Pads
ABS/ESC
- Manufacturer
- Model
- Hardware/Software

Wheels/Tyres

Front
- Wheel
  - Material
  - Dimensions
- Tyres
  - Make
  - Dimensions
  - Model
  - Pressure Unladen (psi)
  - Pressure Laden (psi)
- Weight
  - Weight Unladen (kg)
  - Weight Laden (kg)

Rear
- Wheel
  - Material
  - Dimensions
- Tyres
  - Make
  - Dimensions
  - Model
  - Pressure Unladen (psi)
  - Pressure Laden (psi)
- Weight
  - Weight Unladen (kg)
  - Weight Laden (kg)

Test

Test Date
Test Track
Test Facility
Comments

Conditions

Road Type
Weather
Temperature (ºC)
Track Temperature (ºC)
Humidity %
Wind Speed (km/h)

When in Offline mode, the Session Data will be saved into the VBOX file. This information will be recalled every time the file is loaded into VBOX Test Suite.

When in Online mode, a newly created session will be populated with session data from the previous session.

To save time, you can import and export the session data for other sessions. When you have completed the Session Data, you can export the data to a .vbses file by clicking on the Export button in the Session Data window. The exported file will contain all the session data and can be imported into another session via the Import button in the Session Data window.

Help Section

Help

Test Settings

If you are creating a new test, the Settings window will open when you add the new test. This is where you can define the test parameters.

If you have already added a test and you have it open, you can click on the Configure button to open the Settings window to define or amend the test parameters.

Test Condition

Start Condition

This is where you define when the test will start. Use the dropdown menu to decide if the test is to begin on a trigger, or when a set CAN channel reaches a the user-defined positive or negative value.

Note: If a trigger is used as the start condition, the test will not restart if the trigger is activated within 1 second of the previous trigger activation.

Minimum Trigger Speed

You can enter a minimum speed at which trigger activation becomes valid. If the trigger is detected below this speed, the test will not start.

Use the up and down arrows next to the value boxes to increase/decrease the speed values. You can also type the required speed value directly into the box.

End Speed

This is where you define the speed that will end the test.

Use the up and down arrows next to the value boxes to increase/decrease the speed values. You can also type the required speed value directly into the box.

Corrected Distance

As the trigger may not be activated at exactly the same speed on each run, VBOX Test Suite has a feature that will correct the brake distances to the same speeds.

The corrected trigger distance calculation compensates for the over or under-speed application and normalises the result to a set start speed value maintaining the original initial braking reaction time, as if the brakes had been applied at that exact set speed.

Start Speed (km/h)

Specify the required start speed in km/h.

Use the up and down arrows next to the value boxes to increase/decrease the speed values or type the required speed value directly into the box.

Auto

You can set this to be done automatically to the nearest 10 km/h by ticking the Auto box.

The corrected distance is calculated by using the following equation:

Corrected distance = Trigger Distance * ((Nominated Speed ^ 2 - End speed ^ 2)/(Trigger speed ^ 2 - End speed ^ 2))

Nominated Speed is the speed nearest to 10 km/h (or mph) of the trigger speed.

VBTS_BrakeTrigger_Settings_CorrectedDistance_disabled.svg

MFDD

This is where you to set up the start and end of the Mean Fully Developed Deceleration (MFDD) analysis period.

Percentage

This deceleration figure is used to show the maximum deceleration a vehicle can achieve. It is usually the deceleration between 80% and 10% of the trigger activation speed, the time at which the vehicle is loaded up and braking at its highest achievable level.

The MFDD is calculated by the following formula (using the default 80% – 10% value):

MFDD = ((v_08)² – (v_01)²) / (25.92 * (s_01 – s_08))

Where:

v_08 is the speed at 80% of the brake trigger activation speed.

v_01 is the speed at 10% of the brake trigger activation speed.

s_01 is the distance at which the speed is v_01.

s_08 is the distance at which the speed is v_08.

Speed

MFDD can also be calculated by using speed. To do this, you must select the Speed option and enter the required From and To values (in km/h). The maximum From speed is the same as the entered Start Speed in the Test Condition section.

If the MFDD To value is below the End Speed entered in the Test Condition section, for example a 35 to 5 km/h test with 80 to 10% MFDD values, you will see a notification warning you that the MFDD conditions are invalid. The test will still run, but VBOX Test Suite will not populate MFDD results.

Braking Accuracy Analysis

This area allows you to specify the braking accuracy limit.

When you select 3 or more runs, the Accuracy value will be populated at the bottom of the Results table underneath the Distance column.

Depending on what the percentage limit is, the result box will be highlighted green if the accuracy is below the limit or red if the accuracy exceeds the limit. If you have selected fewer than 3 runs, the box will be highlighted orange.

The braking accuracy analysis is calculated by the following formula:
(standard deviation/average)*10

Wheel Slip Calculation

The software can automatically calibrate wheels speeds before producing a % wheel slip channel.

Click on the + button to add a Wheel Slip Calculation.

Wheel Speed Channel

Select the wheel speed source from the dropdown list of CAN Channels.

You can add mulitple wheel speed channels by clicking on the + icon to the right of the last set channel.

You can remove a set channel by clicking on the X to the right of it.

Time/Distance Between Runs

To ensure that sufficient time or distance has passed since the previous run was completed or started, you can enter a minimum time and/or distance that must elapse before the next run takes place. If a run takes place before the specified time/distance has elapsed, that run will be highlighted in red to indicate an invalid run.

Minimum/Maximum

Select if the settings will apply as the minimum or maximum value.

Time (s)

You can set a maximum time between runs. If a run takes place outside of the specified time, that run will be highlighted in red to indicate an invalid run.

Distance (m)

You can set a maximum distance between runs. If a run takes place outside of the specified distance, that run will be highlighted in red to indicate an invalid run.

Measured from

You can select between two options for the source: it can either measured from the Last completed run (default) or the Last started or completed run (covering situations where a test has been started but then aborted).

Click on the option you want to use for your test.

Start of Test Temperature

As many brake test procedures require the brakes to be between, or below, a certain temperature, you can specify the Temperature channels and add a gauge to the dashboard that states if the temperature is OK, LOW or HIGH.

Channel

Click on the dropdown arrow to see the available channels and select the channel you want to use for the temperature input.

Min Value

Specify the minimum brake temperature for the test.

Use the up and down arrows next to the value boxes to increase/decrease the speed values or type the required speed value directly into the box.

Max Value

Specify the maximum brake temperature for the test.

Use the up and down arrows next to the value boxes to increase/decrease the speed values or type the required speed value directly into the box.

Add

Click on the + button to add another condition.

Delete

Click on the X button to remove a condition.

Pass Condition(s)

You can specify a channel that can be used to easily identify if certain parameters have exceeded a set threshold. Any runs that have exceeded the specified values will be highlighted red to mark it as Failed.

The pass conditions can be set so that the run fails whenever the threshold is exceeded, either at the start of the test, at the end of the test, anytime during the test or averaged during the test.

Channel

Click on the dropdown arrow to see the list of available channels and select the one required for the condition.

Min Value

Specify the minimum value for the condition.

Use the arrow buttons next to the value box to increase/decrease the value or type the required value directly into the value box.

Max Value

Specify the maximum value for the condition.

Use the arrow buttons next to the value box to increase/decrease the value or type the required value directly into the value box.

At

Click on the dropdown arrow to select the required time for the condition.

Anytime
Average
Start of Test
End of Test
Gate X

Add

Click on the + button to add another condition.

Delete

Click on the X button to remove a condition.

Interim result(s)

Display In

Select Columns to display each interim result as a column on the right-hand side of the results table.
Select Separate Table to display each interim result as a row in a separate table next to the results table.

Conditions

You can display intermediary results that are determined by any added Interim Conditions.

Click the + button to add a new interim result condition.

Every: The Interim Result will be displayed Every time VBOX Test Suite notes the set value (e.g. every 10 km/h),

At: The Interim Result will be displayed At an instance of a value (e.g. only at 10 km/h).

Between: The Interim Result will be displayed when between values (e.g. between 30 km/h and 50 km/h).

Select the source channel of the Interim Result and specify the required value.

You can delete a condition by clicking on the X button to the right of the relevant condition.

Advanced

The advanced setting is where you can tell VBOX Test Suite to reset the test when the start condition is met or not.

Reset when start condition is met

By default, this setting will be ticked, and the test will reset every time the start condition is met.

If you untick the Reset when start condition is met option, the test will start when the start conditions are first met and continue until the end condition is met.

Test Results Area

The Test Results area is the area that displays all of the results from the current test. In this area, you can include/exclude results from the Chart area, display the average/max/min values and also easily identify any runs that have not met the pass criteria.

Every time you start a new test (via the START button on the dashboard), or load a new file, a new tab will be added to the Test Results area. This gives you the ability to switch between separate tests or files and compare runs from each. You can remove a session from the Test Results area by clicking on the X icon on the session tab.

Note: Whenever you make any changes to the test configuration, maths channels, vehicle dimensions, test units or session data, Test Suite will perform a file scan to apply the changes to the loaded files and update the Test Results, Map and Chart areas. If you, for any reason, want to cancel this results scan, you can click the red X in the top right corner of the workspace. This will keep the updated settings but will not update the Test Results, Map and Chart areas accordingly.

Rename File

Edit Session Data

By pressing the Edit Data button next to the name of the session in the Test Results area or on the Test Setup tab on the ribbon, you can add vehicle and test information to the session.

When in Offline mode, this information will be saved into the VBOX file, meaning that this information will be recalled every time the file is loaded into VBOX Test Suite.
When in Online mode, a newly created session will be populated with session data from the previous session.

This information will be included in the test report to make it easier to see under what conditions the test was conducted.

To save time, you can import and export the session information for use in other sessions (the entire range of data is exported, not just the visible screen).

Once the session information has been completed, you can export the data to a .vbses file. This file will contain all the session information that can then be imported into the open session information field.

Result Columns

The Test Results area has the following default columns:

Run

Indicates which run number the results relate to, with run one being the first run completed.

There is also a selection box that, when ticked, includes that run in the graph and into the Average/Max/Min/Standard Deviation calculations. Once selected, a coloured square will appear to indicate which colour this run is displayed as on the graph.

Note: If you are loading a file in Offline mode, all valid runs will automatically be ticked.

Start Speed (km/h)

The speed at which the run starts.

Time (s)

The total time the run has taken.

Distance (m)

The total distance travelled in that run.

Corrected Distance (m)

The test distance with the start speed corrected to the nearest 10 km/h, or user specified speed.

Avg Decel (g)

A mathematically calculated Avg Decel using the following formula:
Avg Decel = (v²-u²)/(2s)

Where:

v is the final velocity, measured in m/s.
u is the initial velocity, measured in m/s.
s is the distance, measured in m.

Centre Line Deviation (m)

The total lateral deviation the vehicle has travelled from the initial test path.

MFDD (g)

This is the mean fully developed deceleration value, taking into account the start and end speed % as specified in the MFDD section above.

AMS Distance (m)

Calculates a theoretical braking distance if the vehicle was to decelerate at the MFDD for 100% of the brake stop. It is calculated by the following formula:
AMS Distance = (100% MFDD speed (m/s)²) / (2 * MFDD)

Yaw Angle Deviation (Absolute Max) (degrees)

The difference between the Yaw Angle of the vehicle and the reference yaw angle, which is the 1 second average of the yaw angle before test start.

The software will automatically add columns based on the configuration in the Settings.