General system operation
The system is preconfigured and ready for use, the up and down buttons on the DASH4PRO switch between screens, and each screen is preconfigured for a different brake test. The set button on the DASH4PRO starts and stops the DL2 logging data (there is also a button directly on the DL2 that does the same)
How to change test parameters
The system is supplied with a default set of tests preconfigured, one for each screen of the DASH4PRO:
- Screen 1 is set for 50kph to 2kph
- Screen 2 is set for 100kph to 2kph
- Screen 3 is set for 130kph to 2kph
- Screen 4 is set for 200kph to 2kph
To change the test parameters, there are 2 alternatives:
- To change the parameters from the DASH4PRO, then go to menu 10.1 on the unit, and all parameters can be adjusted. In practice this works well for simple changes, but can be frustrating and slow for extensive changes.
- Alternatively all the tests can be set up from the PC. To do this use the DASH4PRO configuration software. Load the DASH4PRO configuration file, and go to the menu “configuration->Trigger SPEEDBOX tests”. Once the changes are completed, connect the PC to the main system USB port on the DL2 and upload the changes.
Reviewing the brake test results
There are 4 places where you can access the brake test results, each suited to different applications:
- On the DASH4PRO. This is typically used to check that the test was completed okay.
- Stored as a simple ASCII text file on the DL2’s SD card. This is a quick and simple to review all the results that were generated in real time.
- The raw data can be post processed using the “Run Processor” software. This allows processing of a single run, or a whole directory of runs, with new test parameters.
- For complete flexibility the raw data can be loaded into the “Analysis” program. This allows you to view the results that were taken in real time, generate other statistics, as well as carry out any general analysis. This is ideal for any non-standard or specialist applications.
Each of these alternatives is set out below:
DASH4PRO
On the main screens of the DASH4PRO can be configured to display brake testing results. For displaying a few key parameters, it is possible to just display individual braking variables. In the example DASH4PRO layout supplied, this is what has been done, just the path distance and the distance accuracy is shown, which is typically enough to confirm that the test worked. Alternatively, the DASH4PRO can be configured to display all the test results in a “SB text results” window. This has the advantage of displaying more information, including the tabular results – but it can result in a cluttered screen. In addition after a test is completed, the results from the last test are available in menu 10.2. Finally there is also a performance meter mode of the DASH4PRO, under menu 9. In theory this can also be used for simple straight line brake tests, however this mode is not recommended for high accuracy testing, instead it is aimed at simple magazine testing and autosport applications.
SB text files on the DL2
The real time data from the SPEEDBOX are stored on the memory card of the DL2 in 2 ways. Firstly there is a binary “RUN” file that contains all data in a proprietary, but documented, format. In addition the results generated from the SPEEDBOX are also stored in a simple ASCII format, which can be viewed just using a standard text editor. This later file has a SB extension. A separate RUN and SB files are generated for each logged session. If a separate file is required for each test then it is possible to set autostart and autostop conditions on the DL2. Alternatively it is normally simpler to log continuously and have multiple braking tests in a single file.
Post-processing a RUN file - Run Processor tool
The “Run Processor” software can be use to process a single run, or batch process a directory of run files. It has a number of uses, including converting binary RUN files into text suitable for excel or Matlab. For brake test applications the application includes the “performance results” mode. This mode can be used to configure tests in the same way as on the SPEEDBOX, or the DASH4PRO. Up to 10 different tests can be set up in the software and run at the same time, for example the system can be set to do both triggered to stop, and 62kph to 10kph at the same time – something that is not possible in real time. Results can be saved in a CSV format file, or viewed directly in the application and cut and pasted as needed.
Loading RUN data files into Analysis
The data analysis program is extremely comprehensive and powerful piece of software, please refer to the help file for documentation on the operation of this program. However, in brief the “performance calculations“ window is the simplest way to access braking results in the run file.