🌱 Tony's Memex Tony's Intertwingled Memex
Digital Garden | OER Curriculum
Home / Digital Garden / Robotics and Telemetry Tracking Actuator (Computer & Robotics Engineering)

Robotics and Telemetry Tracking Actuator (Computer & Robotics Engineering)

At an autonomous robotics flight testing facility, an automated optical tracking camera mount tracks an inspection drone performing a low-altitude survey. The robotic camera platform is anchored at ground level and rotates along an elevation pitch axis driven by a precision servo-actuator.

The drone flies along a straight, horizontal flight corridor at a constant altitude of h=300.0 metersh = 300.0\text{ meters} directly over the camera base. Real-time GPS and optical flow telemetry indicate the drone flies at a constant horizontal speed of:

v=∣dxdt∣=60.0 m/s(216 km/h)v = \left|\frac{dx}{dt}\right| = 60.0\text{ m/s} \quad (216\text{ km/h})
where x(t)x(t) represents the horizontal distance from the tracking station to the drone coordinate.

The camera elevation angle θ(t)\theta(t) (measured from the horizontal ground up to the drone line-of-sight) satisfies the trigonometric relation:

tan⁡θ=hx\tan\theta = \frac{h}{x}

  1. Formulate the time derivative relation connecting the camera's angular tracking velocity dθdt\frac{d\theta}{dt} to the drone's horizontal flight speed dxdt\frac{dx}{dt} using the Chain Rule on tan⁡θ=hx\tan\theta = \frac{h}{x}.
  2. Determine the exact angular tracking velocity dθdt\frac{d\theta}{dt} required by the servo-motor in radians per second (rad/s\text{rad/s}) and degrees per second (∘/s^\circ/\text{s}) at the instant the drone is at a horizontal distance of x=400.0 metersx = 400.0\text{ meters} approaching the station.
  3. Compute the angular velocity required when the drone is directly overhead (x→0x \to 0), and explain why robotics control engineers must design pan-tilt servo actuators with sufficient angular acceleration bandwidth to prevent gimbal lock or tracking target loss.