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Transactions on Engineering and Computing Sciences - Vol. 12, No. 3

Publication Date: June 25, 2024

DOI:10.14738/tecs.123.17047.

Zosimovych, N. (2024). Hierarchical Flight Control System for Tilt-Rotor Drones. Transactions on Engineering and Computing

Sciences, 12(3). 73-87.

Services for Science and Education – United Kingdom

Hierarchical Flight Control System for Tilt-Rotor Drones

Nickolay Zosimovych

Aerospace Department, National Aviation University NAU, Ukraine

ABSTRACT

This paper presents a hierarchical flight control system for tilt-rotor drones. The

offered approach performs high-level mission goals by gradually confirming them

into machine-level instructions. The learned data from numerous sensors is spread

backside to the greater levels for sensitive decision making. Each vertical take-off

and landing drone are linked through regular wireless communication rules for

accessible multi-agent facility. The proposed flight control system has been

effectively employed on several small tilt-rotor drones and validated in some

applications. Solutions from waypoint navigation, a probabilistic chase-evasion

competition and vision-based object chasing show the capability of the

recommended method for intelligent flying drones.

Keywords: Tilt-rotor drone (TRD), vertical take-off and landing (VTOL), control, vehicle

control language (VCL), vision, strategy, inertial navigation system (INS), global

positioning system (GPS).

INTRODUCTION

Implementation of smart drones has been done potential because of hi-tech innovations in

different areas such as artificial intelligence, flying robotics, wireless communication, and

control systems. There is small skepticism that intelligent drones will be employed to

autonomously run missions, or embedded in numerous structures, and spread our abilities to

identify, mind and action, or replace human attempts in applications where individual action is

threatening, unproductive and/or even impossible.

Fig. 1: Tilt-Rotor Bayraktar DİHA Unmanned Aerial Platform (Turkey) [3]

A flying plane in the sky Description automatically generated

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Transactions on Engineering and Computing Sciences (TECS) Vol 12, Issue 3, June - 2024

Services for Science and Education – United Kingdom

Supporting to this impression, proposed study objects to establish numerous autonomous

negotiators into integrated and intelligent structures with condensed reasoning and control

intricacy, open-mindedness, adaptivity to variations in mission and situation, modularity, and

scalability to achieve intricate assignments competently.

Tilt-Rotor vertical take-off and landing (VTOL) or tilt-rotor drones (TRDs) have got distinctive

flying abilities such as hover, vertical take-off/landing, and sideslip, which cannot be attained

by traditional fixed-wing airplanes [1, 2]. These multipurpose mission modes are effective for

numerous circumstances as well as reconnaissance, ground target tracking, and tasks with

restricted launching space such as a ship deck or in situations that need repeated landings and

take-offs (Fig. 1) [3]. These types of drones integrating are helicopter technology as fixed-wing

aircraft technology.

The last time has seen astonishing advancement in TRD study including design and modeling

[4-7], modern control theory [8-9], and avionics [10-11]. But the recent level still drops quickly

by applying results to most actual applications and utilizing the detailed abilities of the

rotorcraft. Our research has been focused on enhancing the performance of TRDs as

participants of a networked intelligent group containing numerous heterogeneous drones. To

reach this goal, it is important that every mission control system be able with well-capable

autonomy, i.e., abilities to independent sense, mind, plan, and act in expertise with other drones

or ground/ water-based robots or environments. This article shows the combination of a

hierarchical flight management system (FMS) for TRDs that offers autonomy as permitting

management among all team participants. The proposed paper presents three control

approaches:

1. TRD cascade PID control strategy;

2. the dynamic control allocation strategy (from Ref. [7]), so it adapts to a potential drone

configuration change;

3. multi-functional hierarchical FMS strategy [12].

Fig. 2: TRD Cascade PID Control Strategy [6]

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Zosimovych, N. (2024). Hierarchical Flight Control System for Tilt-Rotor Drones. Transactions on Engineering and Computing Sciences, 12(3). 73-87.

URL: http://dx.doi.org/10.14738/tecs.123.17047

Fig. 3: TRD Control Strategy with Dynamic Control Allocation [6]

After determining the TRD dynamic model and calibration of the appropriate aerodynamic

coefficients, for the TRD control, the state variables are operated by a PID controller, and Fig. 2

appears the block diagram of the control strategy. Forces and moments due to rotors and wind

aerodynamics are computed independently.

The general control structure contains two cascade PID controllers, which accept errors from

speed and attitude and provide consistent control amounts [5]. The control of TRD is reached

by applying the negative feedback [13].

Additionally, the current drone controller offers the off-the-shelf controller for namely this type

of drone, it normally needs to load up the appropriate files to represent the required control

pull to every single actuator input, which can only carry the drone with a fixed structure. In its

place, we employed a possible drone structure change (such as an actuator failure).

Consequently, the control diagram becomes like on Ref. [7] (Fig. 3).

So, we use up a multi-differential controller as a non-linear model predictive tracking controller

(Fig. 4).

The former has been successfully validated in various scenarios, as mentioned on Ref. [7]. The

last is especially efficient in focusing on nonlinearity, coupling, input, and state saturations.