HexVIO cuts power use for real-time stereo-inertial tracking
HexVIO: Towards All-Day Stereo-Inertial Tracking Through Commodity DSPs
RoboticsComputer Vision and Pattern Recognition
Summary
Devices like smartphones and XR gadgets need to know where they are in space to work well, which is usually done with visual-inertial odometry (VIO). The authors show how moving part of this process to a special chip that already exists in many devices, called a Hexagon DSP, can save a lot of battery power and make the system faster. Their approach lets such devices track their position continuously all day long while using less energy. This method could make robotics and mobile devices that rely on position tracking more efficient and user-friendly.
What this means in practice
- •For mobile device designers: Design mobile and XR devices that deliver continuous position tracking all day without overheating or draining batteries.$Commercial implications: Enables commercially viable smartphones and XR products that sustain real-time tracking with reduced power usage leveraging existing DSP hardware.
- •For robotics developers: Build robots that perform stereo-inertial localization over long periods by offloading visual processing to embedded DSPs, reducing system load.
Authors
Patrick Wolf, Mateo de Mayo, Daniel Cremers
Abstract
The ability of a device to localize itself within its surroundings is a fundamental prerequisite for spatial computing. Visual-inertial odometry (VIO) has proven to be a cost-effective and accurate solution for this task. Robots, wearables, XR devices, and drones can benefit significantly from efficient implementations of VIO since they allow for cooler, lighter, and cheaper devices with longer battery life and a better user experience. In this work, we propose to enhance the efficiency of a VIO system by leveraging the Hexagon DSP, a commodity co-processor present in many modern smartphones and XR devices. Our approach offloads the visual frontend of a stereo-inertial odometry system to the DSP while keeping the backend on the main CPU. By optimizing the implementation for the DSP architecture, we achieve significant reductions in power consumption and latency compared to CPU-only execution. Our system, HexVIO, demonstrates a 67% reduction in power consumption or an 86% increase in throughput on a commodity smartphone, with the ability to sustain long-term real-time 30 fps tracking for 0.83 W, corresponding to ~18 hours of tracking on the testing device. These results highlight the potential of commodity DSPs for enabling all-day visual-inertial tracking in robotics and mobile devices.