Authored by Matthew Hartman [MSFT]
The HMD Exerciser Kit provides
- USB Plug/Unplug/Multiplexing
- HDMI Plug/Unplug/Multiplexing
- IR User Presence Detection Spoofing
- Independent Display Brightness/Color Detection
- 2x Servo Control with Independent Servo Power
- HMD Audio Level Monitoring
- USB Voltage/Current Polling
The setup is flexible and can be designed to meet your specific test requirements. Here’s an example of how we used the HMD Exerciser Kit in our lab. In this configuration, we have also have the two motion controllers and the HMD on turntables for movement/FOV testing.
HMD Exerciser Kit Hardware
The kit includes two main components. The HMD Exerciser (left) and the HMD Board (right).
The HMD Exerciser is the main unit for all the connections to the HMD and PC. It handles all of the measurements, multiplexing, and PC communication. More details about the components that make up the HMD board are available in the Documentation.
The HMD Board contains the hardware that interacts with the HMD’s displays and presence sensor. The two TCS34725 color sensors are placed to line up with each display. This allows independent brightness/color measurement. The IR photodiode and LED match the typical placement of IR user presence sensors. They are used in combination to spoof user presence or absence. The desired user presence state is controllable via software.
The HMD Board fits in a 3D printed mount which is designed to clip securely into the HMD. This mount is designed for the Acer Windows Mixed Reality HMD.
The HMD Board attaches to the HMD Exerciser using the flat ribbon cable shown above. Each HMD Exerciser can test up to two HMDs with a single PC.
Find more details in the docs here.
HMD Exerciser Kit Software
The HMD Exerciser Kit is controlled either through a command line executable or managed class. The command line utility is available in the MUTT tools, and the managed class is available in the BusIoTools Git repo. Look for more details in the Microsoft Docs.
To get started with the command line tool, identify which ports your HMD is plugged in to on the HMD Exerciser and select those ports to connect the HMD. For this example, we’ll use USB and HDMI port 1.
Next, tell the kit what port (1 or 2) your HMD Board is plugged in to. For this example, we’re using port 1.
After this command, all the display/audio/presence commands will apply to the HMD on port 1. Now we can grab the HMD’s display brightness, display color and audio level. We can also set user presence spoofing if the HMD uses IR user presence detection.
To disconnect the USB or HDMI ports, just set the port to ‘0’ in the command