Federal Aviation Administration
Principal Investigator and Technical Lead
1 August 2015 – 30 June 2016
Total award $63,679
This project seeks to exploit derived angle-of-attack (AOA, ##\alpha##) and flightpath angles (##\gamma##) from low cost Attitude Heading Reference System (AHRS) COTS systems found in GA aircraft. The feasibility of derived AOA will be evaluated for use cases of displays, envelope protection, and fly-by-wire flight control systems. It is expected that the results of this work will be a) recommended minimum performance standards for the algorithm and AHRS device, and b) the criteria for each use case when using AHRS that can be codified into a standard or a circular. The aircraft considered will be Part 23 aircraft (such as C-172, Cirrus SR-22, Lancair 350 and light jets). In addition, hybrid aircraft (Part 23 and part 27) may be considered. The COTS AHRS to be evaluated are those typically found in aircraft and will include 3 systems, 1 of each from the following categories. 1) Installed AHRS (such as Garmin, Aspen, Avidyne) 2) Portable AHRS (such as iLevil, Stratus, Sagetech) 3)Low Cost AHRS typically found on UAV’s (such as Pixhawk, Airware). Phase I will consist of an offline simulation study in the context of intended function, and benchmarks of existing sensors. The simulation engine which will generate inputs to the algorithms is XPlane 10, used in the VSCL Engineering Flight Simulator. The initial use will be an AHRS modeled as a fully integrated input-output sensor system.
TECHNICAL OBJECTIVES
The proposed work seeks to understand how the various COTS AHRS component characteristics affect the usability of derived AOA solutions by conducting a simulation study which will investigate:
- Sensor Accuracy
- Dynamic response
- Error analysis
- Sensitivity of derived AOA from equations
- Parameters
- GPS update rate
- Vertical airmass motion (steady-state and gust)
Working with me on this program are Research Assistants:
- Madison Treat, M.S. student