The new Intel RealSense Tracking Camera T265 was designed for applications such as robotics, drones, and augmented/virtual reality (AR/VR). This US$199 piece of hardware uses proprietary visual inertial odometry simultaneous localization and mapping, can be already pre-ordered, and shipments will begin at the end of February.
https://www.notebookcheck.net/Intel-intros-the-RealSense-Tracking-Camera-T265-for-autonomous-devices.397641.0.html