System Identification of an S500 Quadrotor UAV

Abstract

The S500 is a kit-built quad-rotor aircraft measuring 500 mm diagonally from motor to motor and weighs 3 pounds with a 3-cell 5200 mAh battery installed. The aircraft is flight tested to obtain longitudinal and lateral-directional models of the bare airframe using frequency-response system identification. Frequency sweeps are flown in longitudinal, lateral, collective, and pedal inputs in the stabilize flight mode of PX4 autopilot. The frequency responses are used to identify the longitudinal and lateral-directional state-space models of the vehicle in hover with the cost functions, Cramer-Rao bounds, and insensitivity of both models within acceptably low bounds. The models reveal an unstable oscillatory mode in longitudinal and lateral-directional motion, as is typical for rotorcraft in hover. The models show good agreement with the frequency data and time-domain doublet data and are suitable for future control development on the S500 quad-rotor.

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Document Details

Document Type
Technical Report
Publication Date
May 31, 2023
Accession Number
AD1202345

Entities

People

  • Judson T. Babcock

Tags

DTIC Thesaurus Topics

  • Accuracy
  • Air Force
  • Aircrafts
  • Airframes
  • Automatic Pilots
  • Control Systems
  • Flight Control Systems
  • Frequency
  • Frequency Domain
  • Frequency Response
  • Helicopters
  • Multiple Input Multiple Output
  • Rotary Wing Aircraft
  • Simulations
  • Time Domain
  • Transfer Functions
  • Vehicles

Readers

  • Aviation Science / Aeronautics.
  • Control Systems Engineering.
  • Electrical Engineering

Technology Areas

  • Space
  • Space - Hall-Effect Thruster
  • Space - Spacecraft Maneuvers