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A method to generate vehicle maneuvering forces from a propulsor alone has been applied to a generic undersea vehicle. Open and ducted post-swirl propulsors were configured with an upstream rotor and downstream stator row. During normal operation, the downstream stator blades are all situated at the same pitch angle and generate a roll moment to counter the torque produced by the rotor. By varying...
A hybrid aerial vehicle (HAV), featured combination of a quadrotor system and a fixed-wing system, is one of the most promising configurations having both a vertical take-off and landing (VTOL) capability and high cruise performance. In this paper, a HAV has been designed and prototyped to analyze the performance of the HAV. The specifications of the HAV are summarized. The aerodynamic coefficients...
This paper presents fuzzy self-tuning PID controller for controlling the altitude of the quadrotor. Although the PID controllers have many advantages, it has a limitation that the main term gains called proportional gain, integration gain, and derivative gain have to be tuned manually. One of a solution to manage its limitation is adding the special feature called self-tuning. So, a fuzzy self-tuning...
Unmanned aerial vehicles (UAV) can potentially carry out a wide range of tasks and operate in hazardous conditions. Some tasks require complex and precise aircraft movements in the presence of external disturbances. In this paper, a design of non-flat multirotor configuration (NFH6) is presented. Through dynamic model, it is shown that flat multirotor configurations share inherent underactuated condition...
The underactuation of the standard quadrotor(four independent control input versus six output) is a serious problem which can be solved by tilting four rotors. The steering wheel is installed on each axle of the original quadrotor so that the quadrotor turns into an actuation system(eight-input versus six-output). In this paper, the dynamic model of the tilt-quadrotor is established, and the validity...
Quadrotors are becoming a major platform for both industrial and research activities, increasing the requirements for precise and dynamic control. Best control can be achieved by directly controlling the individual rotor thrust forces, which, during flight, can only be estimated. An identification of the thrust generation mechanism, and subsequent exploitation of this relation in the quadrotor's command...
This paper presents the design of the Interacting-BoomCopter (I-BoomCopter) unmanned aerial vehicle (UAV), designed specifically for environmental interactions. The novel design consists of a horizontally mounted four-blade reversible propeller on a front boom that is attached to a standard tri-rotor UAV configuration. A custom end-effector and force sensor is placed at the end of the front boom for...
The goal of Piccolissimo is to create a small, simple, and self-powered flying vehicle. Piccolissimo has just one motor and two rigid bodies, which are propellers that spin in opposite directions. The mass distribution and relative rotor speeds are designed to maintain passive stability in hover. Cartesian velocity control is obtained by introducing an asymmetry in the rotation axis of the two rotating...
Standard hexarotors are often mistakenly considered ‘by definition’ fail-safe multi-rotor platforms because of the two additional propellers when compared to quadrotors. However this is not true, in fact, a standard hexarotor cannot statically hover with ‘only’ five propellers. In this paper we provide a set of new general algebraic conditions to ensure static hover for any multi-rotor platform with...
The concept of utilizing the Coandia effect to produce stable flight in saucer type Aerial Vehicles (AV) was first conceived in 1935 by Henri Marie Coanda. Coanda's proposed AV design remained a relatively unexplored curiosity for decades until the recent surge in popularity of small Unmanned Aerial Vehicles (UAV) revitalized interest in the topic. Coandä effect UAV offer some distinct advantages...
In contrast to the conventional underactuated quadrotor, an over-actuated tilt-rotor quadcopter equipped with four tilting rotors can fly the arbitrary position trajectory while maintaining the desired attitude. We study the translational and rotational dynamic model for the tilt-rotor quadcopter associated with disturbances and uncertainties. Using the tilting rotors, we design two sliding mode controls...
Usually, robot is designed by using only one locomotion mechanism, such as walking, hopping, and jumping. The reason, among others, are simplicity, saving energy, and focus on single task and mission. This paper deal with design and implementation of multimodal flying and crawling robot by using adaptive morphology. The aim of this development is to provide robot platform that could achieve multiple...
In this paper, an evaluation approach of recoverable performance for post-fault quadrotors is investigated. Both propeller faults and failures are considered, such as loss of partial propeller effectiveness and loss of one or more propellers. The main contribution is to propose a method to compute recoverable set for different faulty conditions using sum of squares (SOS). The recoverable set is an...
Advancements in control theory and the miniaturization of microelectronics has led to significant improvements in the aerial characteristics and performance of single rotor aerial crafts. These single rotor aerial crafts are of particular interest as they can be considered true hybrids between traditional fixed-wing crafts and the maneuverable multi-rotor platforms, allowing both VTOL capabilities...
Many articles have been written on unmanned flying vehicle with multiple rotors. Manipulation of rotor speed is the basic approach for controlling the object. This article considers state feedback approach for controlling rotor speed fixed on one end of a lever of which central point is fixed as pivot point and the other end of the lever has some passive counterweight. Our goal is to balance the seesaw...
Conventional quadrotor UAVs have crucial underactuation limitations. This appears in the coupling between the roll angle and the movement in y-direction, and between the pitch angle and the movement in x-direction. The quadrotor capability of hovering with either roll or pitch angle is restricted due to these limitations. In this paper, a novel design modification is proposed in order to increase...
This paper focuses on a convertible unmanned aerial vehicle (CUAV) whose main characteristics is to perform hover flight for launch or recovery, and horizontal mode during cruise. The dynamic model is obtained using the Newton-Euler approach and it considers the aerodynamic effects. An adaptive backstepping control, based on quaternions, is proposed for the complete operation of the CUAV. The closed-loop...
This paper presents aerodynamic analysis of an unmanned small-scaled gyroplane with a rotor having cyclic pitch system. A comprehensive nonlinear model is derived for it which involves force and moment generation mechanism for the flying vehicle. The nonlinear model is linearized with approximations and deduced on a prescribed flight condition. Our gyroplane dynamic modal response is further reconfigured...
This paper presents a transition-flight mathematical model of a civil tilt-rotor VTOL unmanned aerial vehicle (UAV) TURAC. Forces and moments acting on the UAV body are calculated using Newton's second law. Aerodynamic effects of free airstream and propeller airstream are defined separately. CFD analyses are performed to specify aerodynamic coefficients for transitional flight regime. The trim point...
Single Rotor based Vertical Take Off and Landing systems are more prone to stability issues than normal aircraft. The main factors causing instability are anti torque, pitching and rolling. Anti torque, which causes the body of the aircraft to turn in the opposite direction to the rotor, is generated as the engine turns the rotor against the air. Pitching and rolling, on the other hand, can be caused...
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