What is this?

This project is a rapid and simple example of how to start a background process for listening to HTC Vive Lighthouse tracking data. It was mostly written to serve as example code for the OpenVR Quick Start Guide. The project interfaces with Valve's OpenVR SDK. It was developed cross platform, so the project should compile on both Windows and Linux systems. If you find that this is not the case, open an issue or contact the developer.

Make sure to see this entry on the VR Controls repository's troubleshooting guide if you are having issues trying to interface with OpenVR/this project on Linux.

How do I run it?

First, complete the Vive Setup Guide to ensure proper hardware/software setup of the HTC Vive/SteamVR/OpenVR SDK.

After the setup is complete, this project needs to be built from source. Follow the step by step guide below to compile the project.

How do I compile it?

Make sure g++ and python are installed. If using cygwin for Windows (recommended), these packages may need to be installed from the cygwin installer.

Have openvr cloned somewhere convenient

The following script should properly build and run the project:

# Install Steam and SteamVR

git clone https://github.com/osudrl/OpenVR-Tracking-Example.git ViveTrack
cd ViveTrack
python build.py ~/path/to/openvr/
bash build/compile.sh

# Start up SteamVR and connect the Vive

./build/track

More information about compiling this project can be found on the Compile Guide.

How do I play it?

Coordinates Only

The easiest way to ensure that the controllers and HMD are tracking properly is to have the program print the coordinates it sees for the devices. When running the tracking example, to have it only print the coordinates of the devices use the -c option.

bash build/compile.sh
./build/track -c

Coordinates Visualized in Vpython

1. Install vpython on conda

• conda install -v vpython vpython

2. To run, use ./build/track -c | python mirror-coords.py.

Opstacle-sensing game

However, to further demonstrate the tracking potential of the Vive system, the bulk of the code on this branch is for a tool where the user draws around obstacles in the room using the Vive controllers so that, when in sensing mode, the controllers can rumble when nearby the obstacles as a "warning".

Defining a cylinder around a real-world obstacle

As of now, the only shapes that can be used for collision testing are cylinders with a height in the direction of the y-axis. Here are the steps within the program to define an obstacle (cylinder):

1. Enter DrawingMode. You can toggle between DrawingMode and SensingMode with the ApplicationMenu button above the trackpad. You have entered DrawingMode when the controller rumbles breifly after pressing the ApplicationMenu button.
2. The next step defines a 2D circle in the xz plane. Hold down the trigger with the tip of the controller touching one edge of your obstacle and release while touching the opposide edge of the obstacle. The distance between the two points will be the cirle's diameter and the midpoint betwen the two will become the center of the circle.

3. By default, the y-axis bounds of the cylinder extend forever in both directions.

4. Define vertical boundaries by holding down the grip button with the controller level to the top of the obstacle and releasing level with the bottom of the obstacle.

5. Switch to SensingMode by pressing the ApplicationMenu button, and test to see if the controllers will rumble if nearby the obstacle.

Extending vertical bounds infinitely in one direction

Often, the obstacles you might want to test with are on the floor and don't have any empty space under them. To define the obstacle with infinite depth going downwards so that you don't have to rub your Vive controllers on the ground to properly define the obstacle, use the following control:

1. Follow steps 1 & 2 above.
2. Hold down the grip while the controller is level with the top of the obstacle.
3. Lower the controller an arbitrary distance below where the grip was originally heald.
4. Release the grip and rapidly press and release the grip again to extend the boundary forever in that direction.

Drawing multiple cylinders

With the current implementation, up to ten different cylinders can be drawn around obstacles. While in DrawingMode, the controller will occasionally rumble the current index of cylinder that is being edited (starting with one). To move to the next cylinder, press the right side of the touchpad. To edit a previous cylinder, press the left side.

When moving to different cylinder, the controllers should vibrate the current index that has been selected.

Controls Summary

All of the following controls (except toggling modes with the ApplicationMenu button) only work in DrawingMode.

Button	Function
Application Menu	Toggle from DrawingMode to SensingMode and back
Trigger	Hold to define or reset the circle that is a cross-section of the cylinder in the xz plane
Grip	Hold to define the vertical bounds of the current cylinder
Trackpad (left)	Switch work to the previous cylinder
Trackpad (right)	Switch work to the next cylinder
Trackpad (up)	Press to vibrate the index of the cylinder currently being worked on
Trackpad (down)	Reset/delete the cylinder at the current index

Troubleshooting:

See the Vive troubleshooting guide for Vive/SteamVR issues that were solved.

Feedback

Written by Kevin Kellar for Oregon State University's Dynamic Robotics Laboratory. For issues, comments, or suggestions with this guide, contact the developer or open an issue.