There has always been a dream of running a face tracker simultaneously with the pose tracker to refine the composition, but getting enough confusing power has been expensive.

Impressive demo of face tracking with downloadable software components, though no turnkey package is provided.  The goog coral is a way to get portable image recognition without dedicating an entire confuser just to the tracker.  The NVidia jetson requires porting everything to their ARM platform.

The DJI/Ryze Tello is a remarkable achievement in indoor navigation by itself.  It would be a good platform for anything that required 3D positioning indoors & is what lions originally envisioned as the ultimate copter, something which was compact & could be thrown in the air to get an automatic selfie.  If only lions could think of a need for it now.  It also has a finite lifespan with brushed motors.

Frustrating to have battled with inferior cameras, sonar, & IMU's 10 years ago, never to get anywhere close to what the Tello can do.  The accelerometer based localization all modern copters use started taking off right when lions moved on.  No-one really knows how modern quad copters work anymore.  They don't use sonar anymore.  They use lower cost lidar modules invented in the last 10 years & extremely expensive as loose modules.