A talk from the Develop Track at AWE USA 2018 - the World's #1 XR Conference & Expo in Santa Clara, California May 30- June 1, 2018. Michael Ciuffo (Synapse Product Development): Addressing the Critical Tradeoffs During VR Hardware Development General Purpose? or Application Specific? Technical limitations still make VR hardware cost-prohibitive for many, so careful consideration of the application and market must be applied very early in the development process. Audience members will acquire insight on how to avoid common pitfalls made during product conceptualization and leave with a good understanding of the strengths and weaknesses of outside-in optical tracking technologies. This is a pragmatic approach to addressing the critical tradeoffs during VR hardware development. http://AugmentedWorldExpo.com

1. Assessing Critical Tradeoffs During VR
Hardware Development
Michael Ciuffo

3. Involvement in VR
● Valve/Synapse, SteamVR Tracking, the HTC Vive, and you (the license)...
● Outline the story
○ Synapse started working with Valve on their VR system in Oct, 2014
○ Collaborated on base stations leading up to the developer release in June, 2015
○ HTC was already integrating the tech into the HTC Vive which was released in April,
2016
○ Valve announced royalty free licensing of SteamVR Tracking in Aug, 2016
○ Developed the SteamVR Tracking reference design released in Sept, 2016
○ Organized and hosted SteamVR Tracking training courses Sept, 2016 - Today
○ Continue to develop firmware and assist partners integrating SteamVR tracking into
their products
Synapse Confidential

4. Common VR Pitfalls
● VR hardware is difficult to “Tack-on” to an existing design.
● VR-centric design is critical to reducing cost.
● Adding VR tracking to a product will typically require a change
to its industrial design.

5. Development process
Simulate Prototype Build

6. Evaluating Tracking Performance
https://partner.steamgames.com/vrlicensing

7. Common VR Pitfalls
● VR hardware is difficult to “Tack-on” to an existing design.
● VR-centric design is critical to reducing cost.
● Adding VR to a product will typically require a change to its
industrial design.

8. The Universal Tracking Puck

12. Case Study: “Blaster” VR Accessory
https://www.thingiverse.com/thing:2331113

13. https://www.thingiverse.com/thing:2331113

16. https://www.thingiverse.com/thing:2331113

18. Tracker on side
Tracker on tip

19. Optical Tracking Performance Vs Speed
● SteamVR base stations only update every 60Hz
● Dramatic motion may only get a few updates over sweep
● Inertial Measurement Unit (IMU) fills the gaps with “Dead
Reckoning”

20. Physics!
User sweeps 0.8m long blaster 90
degrees from patrol ready to firing
stance in 200ms.
Vtracker = 0.5 x π x 0.8m / 0.2s = 6.3m/s
atracker = (6.3m/s)2 / 0.8m = 50m/s2
50m/s2 = 5.1g Minimum!
0.8m
https://www.thingiverse.com/thing:2331113

21. MPU 6500 Datasheet

22. How do you avoid clipping the IMU?
● Move the IMU somewhere else
● Buy a better IMU

23. Vtracker = 0.5 x π x 0.3m / 0.2s = 2.36m/s
atracker = (6.3m/s)2 / 0.3m = 18.5m/s2
18.5m/s2 = 1.8g
0.3m
https://www.thingiverse.com/thing:2331113
Move the IMU

24. Buy a better IMU
MPU6500 ADXL357
Range ±8 ±40
Resolution 4096 LSB/g 12,800 LSB/g
Package size 3x3mm 6x6mm
Voltage 1.8-3.3V 2.5-3.6V
Maximum Bandwidth 1kHz 3.9kHz

25. Buy a better IMU
MPU6500 ADXL357
Range ±8 ±40
Resolution 4096 LSB/g 12,800 LSB/g
Package size 3x3mm 6x6mm
Voltage 1.8-3.3V 2.5-3.6V
Maximum Bandwidth 1kHz 3.9kHz
Cost (@5000 units) $3.51 $50

26. Common VR Pitfalls
● VR hardware is difficult to “Tack-on” to an existing design.
● VR-centric design is critical to reducing cost.
● Adding VR to a product will typically require a chance to its
industrial design.

27. So what do you do?
Integrate VR design principles into your product.

28. ● Best coverage of sensors
● Most flexibility with IMU placement
https://www.thingiverse.com/thing:2331113
Integrate Sensors

29. ● Device shape may not facilitate
ideal sensor placement
https://www.thingiverse.com/thing:2331113
Tracking Trouble

30. ● Modify the physical appearance of
the device to accommodate sensor
placement
https://www.thingiverse.com/thing:2331113
Modify Industrial
Design

31. ● Better VR tracking shapes allow for
better tracking performance
https://www.thingiverse.com/thing:2331113
Modify Industrial
Design

32. Common VR Pitfalls
● VR hardware is difficult to “Tack-on” to an existing design.
● VR-centric design is critical to reducing cost.
● Adding VR to a product will typically require a change to its
industrial design.

33. Tracker on blaster tip
Integrated Design

34. Closing Tips
● Acquaint your design team with VR design principles early
● Allow mechanical and electrical engineers to work closely to
keep manufacturing costs down
● Simulate often
● Prototype early

35. Next Steps
● SteamVR Tracking License
● SteamVR Tracking Class
Synapse Confidential