Development and Flight Testing of a Flight Control Law for Autonomous Operations Research on the RASCAL JUH-60A

Abstract

A critical element of rotorcraft autonomy is a flight control system that can operate harmoniously with the various autonomy components that depend on it. This is particularly true for highly interactive components, such as obstacle field navigation (OFN), where the vehicle navigation course is constantly being altered as more terrain information is gathered. This paper describes the development, integration, and flight-testing of an autonomous flight control system (AFCS) on a JUH-60A research helicopter. Flight-test results include control law validation using frequency domain analysis and performance characteristics using both ADS-33E mission task elements and path-error measurements. These performance data are then used to configure a risk minimizing OFN algorithm with the AFCS. The integrated OFN algorithm and AFCS are demonstrated in flight by navigating autonomously through 23 mi of mountainous terrain.

Autonomous Black Hawk in Flight: Obstacle Field Navigation and Landing‐site Selection on the RASCAL JUH‐60A

“…The geometric planner uses a parameter for minimum safe distance from the center of gravity of the helicopter. The path‐error measurements from ARP‐RASCAL Phase 1 (Takahashi et al., ) were used to determine a safety margin of 40 m in the horizontal and 30 m in the vertical direction. Table presents a summary of parameter changes relative to the RMAX.…”

“…Turn‐Climb maneuver path‐error results from ARP‐RASCAL Phase 1 normalized by rotor diameter versus velocity; flight and simulation (Takahashi et al., ).…”

“…Decel‐Turn‐Accel path error versus acceleration results from ARP‐RASCAL Phase 1; flight and simulation (Takahashi et al., ).…”

“…This is being accomplished using the Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) JUH‐60A Black Hawk (Figure ) (Moralez et al., ; Turner, 2001). The first phase of the effort, namely development of the autonomous flight control system (AFCS), was presented at the 2012 AHS Forum (Takahashi et al., ). This paper describes the next phase, which is the development and testing of OFN and SLAD on RASCAL.…”

“…This paper describes the next phase, which is the development and testing of OFN and SLAD on RASCAL. This paper, along with Takahashi et al (), shows the process of porting the autonomous flight software from the RMAX platform to the full‐scale helicopter. Only 28 flight hours were spent in the run‐up to the first OFN and SLAD tests on RASCAL; the small number of hours demonstrates how successful this process has been.…”