Taylor Made Golf has a research and testing facility that we did work for.  This particular test they needed to measure the velocity of the golf ball coming off of the head of one of their new golf clubs as well as count the number of hits the golf club makes before wearing out.  Fatigue testing is the technical term.  The engineer set to work building the VeloBox.  Designing the circuits, laying out the board and writing the firmware in C and the software control program in C++, the VeloBox was used as a test apparatus controller that triggered at the launch of a golf ball.  Velocity was measured as the golf ball cut the laser beam and the data collected and stored on a micro SD card.  Capacitance touch buttons were the added “touch”.

Here are the specifications if you’re interested:

Header Pinout

Pin Signal Direction
1 Laser Signal #1 Input
2 Laser Ground Output
3 Laser Power  (+12VDC) Output
4 Laser Signal #2 Input
5 Power (+12VDC) Input
6 Power Ground Input
7 Trigger Signal #2 Output
8 Trigger Ground Output

Velocity Measurements

While the system is powered it will display ball velocity and ball count. To zero the ball count while not in record mode press the STOP button.

Record Mode

Press the RECORD/PAUSE button to start logging the Ball Count, Laser Cut Time, and the Ball Velocity to file.  The current filename will be displayed in the lower right hand corner of the display.

The Ball Count will automatically zero when Record Mode is first entered.  The filename will auto increment with each new record session.

 

Pause Mode

Press the RECORD/PAUSE during recording to enter the paused state.  In this state ball velocities are measured and displayed but not recorded in the file.

Stop Mode

Press the STOP button while in record mode or pause mode to end the recording session and close the file.

Configuration

Located on the micro-SD card is a file called config.txt.  This file contains the necessary information to setup the Velocity Measurement Box for operation.  It contains the following information:

Example Configuration Setting Units Precision Description
1.2345 Laser Spacing in x.xxxx The distance between the laser beams
2.5 Trigger Velocity mph x.x Above this threshold the outputs fire
10 Signal #1 Delay Time ms x Delay for x ms then raise the output signal #1
5 Signal #2 On Time ms x Delay for x ms then lower the output signal #1
10 Signal #2 Delay Time ms x Delay for x ms then raise the output signal #2
5 Signal #2 On Time ms x Delay for x ms then lower the output signal #2
1 Laser Trigger Edge 0 or 1 Measures on this Edge (0=Falling, 1=Rising)

The “VeloBox V1.0.exe” software contains a useful tool in the Configuration section to modify this file.  Follow these steps to update the configuration:

  1. Attach the box to USB and allow it to connect
  2. Run the VeloBox V1.0.exe” software
  3. Click the Open button and locate the config.txt file on the newly acquired mass storage device (note: depending on your system the drive letter may be different)
  4. Click Open
  5. Using the edit boxes modify the values you wish to change
  6. Click the Save button
  7. Detach from USB and Re-Power the Velocity Measurement Box – The new settings will be read and initialized into the box.

To Download the Datafiles

  1. Connect the Velocity Measurement Box to USB
  2. The box will show up as a USB attached mass storage device (like a thumb drive).
  3. Copy / Delete / Open any of the desired .csv files

 To Load New Firmware

  1. Connect the Velocity Measurement Box to USB
  2. Start the “VeloBox V1.0.exe” Software and allow the USB to connect
  3. Click the “Prepare for Bootload” button
  4. Wait until the USB detects the detachment of the USB device
  5. Start the “HIDBootloader.exe” software and allow the USB to connect
  6. Click the “Open Hex File” button and select the desired file to download.
  7. Click the “Program/Verify” button
  8. When the programming is complete – Click the “Reset Device” button
  9. The USB device will detach from the HIDBootloader software and then re-attach to the VeloBox software.