Modeling and Incremental Nonlinear Dynamic Inversion Control of a Novel Unmanned Tiltrotor

Automatic control of convertible fixed-wing drones with vectorized thrust

“…Note that i) this model encompasses the zero force assumption commonly made in the case of VTOL vehicles moving slowly (c 0 = c 0 = 0, O(v a ) = 0), and ii) the non-dependence of this model upon the tilt angle θ is equivalent to assuming that modifications of the thrust direction do not (little, in practice) affect the aircraft aerodynamics. One easily verifies that this model is also compatible with the general relations (5) and (6), in particular when the lateral airspeed vanishes. In this latter case (7)…”

“…This transition is typically performed by implementing an ad hoc scheduling policy, when the aircraft moves horizontally and reaches a certain airspeed, either during an acceleration phase (hovering to cruising) or during a deceleration (cruising to hovering). A common practice is to modify the thrust tilt angle in relation to the airspeed [1], [4]- [6]. Taking advantage of the thrust tilting degree of freedom to minimize the thrust intensity is evoked in [7] as a perspective worth to be investigated.…”

Survey on Flight Control Technology for Large-Scale Helicopter

“…However, the high sensitivity to model uncertainties is the main shortcoming of the NDI [58], which motivates the development of INDI. In the past few years, many achievements have been applied to solve flight control problems for fixed-wing UAV [59], spacecraft [60], large-scale helicopter [61], tiltrotor UAV [62], quadrotor MAV [63], and so forth. According to Figure 5, the INDI control architecture implements an RC mode using Apache's limited authority setting.…”

Optimal control of thrust-vectored VTOL UAV in high-manoeuvering transition flight

“…In recent years, advances in the field of automatic control and the increasing popularity of UAV platforms have revitalised research activities on VTOL UAVs, although very few programs have evolved to actual production and flight test of a prototype (1) . The problem of transition manoeuvers has been studied based on different type of UAVs, such as fixedwing aircraft equipped with vectored thrust and lift fan (1,2) , tilt-rotor aircraft (2)(3)(4) , tail-sitter (5) , ducted-fan VTOL aircraft (6) , and tilt-wing aircraft (7,8) . The research of thrust-vectoring attitude/position control of quadrotor UAVs with two orthogonal tilting axes are worth mentioning.…”

“…Due to the redundancy of the effectors governing the aircraft during the transition flight, control allocation methods have been considered. At present, various control allocation methods in aircraft applications have been widely used, such as pseudo-inverse (11) , daisy chaining (1) , direct control allocation (12) , optimisation-based control allocation methods (13,14) and so on. Most research assumed the control model is globally or locally linear.…”