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This paper presents an extended kinematics and dynamics of the articulated tracked vehicles (ATV) used in many applications. The velocity of the front and the rear vehicle are firstly analysed and the kinematics of ATV is built, according to which the steer radius and the track velocity can be obtained. Then we analyse the force and moment acting on the ATV running on the firm ground and the soft...
This paper presents the control framework under development within the DexROV Horizon 2020 project, for the execution of maintenance and inspection tasks by a semi-autonomous ROV. The work exploits a task priority based kinematic inversion developed by the authors, extending it to encompass also a force regulation task. A way to manage transitions between the different DexROV missions is also given...
Conventional motion planners for wheeled vehicles often attempt to prevent wheel slipping or even assume no-slipping condition. However, in some practical situations slipping can be useful. The purpose of this work is construct a motion planning strategy for tail-slide vehicles where the rear wheel is slipping. First we develop a dynamic model of a four-wheeled vehicle by combining an extended 2D-model...
To investigate aeroelastic effects of model flexible wings on aerodynamic performance in forward flapping flight, a monolithic approach and a MATLAB program were established and built based on the Peter's unsteady flow theory and finite element analyses. The kinematic parameters, including flapping stroke angle, flapping frequency and forward velocity were studied to investigate the effect on aerodynamics...
A homing control law for a quadrotor is presented to drive the vehicle towards a moving target at constant longitudinal velocity. The vehicle is driven to the homing point through force control with an inner-outer loop control strategy. For the outerloop, the position and velocity features are exploited to derive a control law that directs the vehicle to the homing target while ensuring it never collides...
Here we present a suite of theoretical, computational, and experimental studies culminating in the first aerial and aquatic capable insect-scale robot. We develop a computational fluid dynamics (CFD) simulation to model fluid-wing interaction in air and water. From CFD and a system dynamics analysis we predict that a multi-modal flapping strategy will enable locomotion in both air and water for a...
This paper mainly deals with the maneuverability capabilities of the propeller-fin-driven underwater vehicle. The nonlinear dynamic model is firstly set up, numerical simulations of kinematic behaviors in the horizontal plane, vertical plane and three-dimensional space are performed respectively to verify the nonlinear dynamic model. Then, Z-shaped steering method with a positive and identical negative...
In this paper, nonlinear controllers are designed for an accurate path-following of a track vehicle towing an active implement, which is steered and driven, in off-road terrains like farms where longitudinal and lateral slips at front tracks and rear steerable wheels are inevitable. These controllers are based on path offset values and a partial dynamic model. The controller is designed to minimize...
Within the framework of the Italian national project MARIS (Marine Autonomous Robotics for InterventionS), in this paper a control law based on a virtual decomposition approach for underwater vehicles carrying a n-degrees-of-freedom manipulator is presented. The control law, already known in the literature, has been customized for the specific set-up of MARIS. Being based on the Newton-Euler formulation,...
The determination of dynamic forces acting on a Flapping Wing Micro Aerial Vehicle (FWMAV) is a challenging task due to the unsteady nature of force generation mechanisms. To assure a proper force identification in future researches, this work compares two different methods to obtain the longitudinal forces acting on FWMAVs and discusses their applicability regions. The methods were 1) calculation...
Because of its comprehensive and flexible sporty performance, omni-directional mobile platform is widely used in industrial production, daily life as well as military fields. Disposed on four terminals of the vehicle body, each wheel's movement is controlled by an independent motor respectively. In this paper, we provide a structural analysis and motion resolving solution to the platform based on...
In this paper, inspired by Lagrangian mechanics, a marine craft is regarded as a mechanical system subject to both holonomic and nonholonomic constraints. Then, the forces that secure fulfilment of the constraints are derived. The proposed method is used to design a controller which makes the craft converge to straight-line paths with an exponential rate. A method to handle underactuation in sway...
With mathematical model of a double track vehicle the mechanism for which suspension bushing stiffness affects on vehicle steady-state yaw response behavior is explained. A vehicle model including front McPherson suspension, rear multilink suspension, power transmission system, steering system, tires and body etc. is built by ADAMS/CAR. With the ADAMS/CAR vehicle model, influence of lateral and longitudinal...
According to the difference between electric vehicles and traditional vehicles, the transmission system of electric vehicles needs corresponding changes to meet requirements of electric vehicles. This paper studied on the integration of double trailing arm suspension and electric engine. The structure of the system was analyzed in detail. And the UG models were established. The transmission strategy...
Biological Inspiration for the design of flapping wing vehicles has been the source of numerous design efforts in the field of Micro Aerial Vehicle (MAV) development. For flapping flight in small birds and insects, high lift generation is typically a result of unsteady fluid flow phenomena. Our previous studies have conceptualized and demonstrated how a dragonfly inspired Quad-Winged Vehicle (QV)...
In order to realize stable lateral motion of the supercavitating vehicles in horizontal plane. First based on supercavitating vehicle dynamic characteristics and motion state analysis, using fuzzy logic method to the analysis on planing force, improvement kinematics equation of supercavitating vehicle on horizontal plane. Second useing state variable feedback exact linearization method to linearize...
The paper is concerned with a vehicle where each front wheel is equipped with a steering equipment. Aim of the paper is to analyze the behavior of the resulting driving apparatus during the steering maneuver in order to subsequently develop a suitable control system. The analysis is carried out in two stages, termed kinematic and dynamic. The kinematic analysis describes the steering maneuver when...
The article proposes a feedback control system for path following in presence of obstacles that is an extension of previous work and is made of two components: (i) a sensor-based, real-time model that generates and periodically updates the path on-line in order to avoid both known and unforeseen obstacles, and (ii) a feedback-control model that is capable of driving a unicycle vehicle along the collision...
Hydrodynamics of underwater supercavitating vehicles are characterized by coupling relationship between body and cavitation. While maneuvering, supercavitating vehicle depends on a bank-to-turn strategy for making a turn, and could not be described exactly by the kinematic model built under the condition of straight line navigation. Based on cavitation theory of unattached expansion, the paper establishes...
The world's first robotic insect capable of vertical takeoff was developed and demonstrated by the Harvard Microrobotics Lab. This vehicle consisted of a single power actuator that drove both wings symmetrically. In this case, there was no method to generate body torques, only lift could be modulated. The Harvard Microrobotics Lab has modified this configuration to include not only a single power...
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