ANTI-SWAY TRACKING CONTROL OF OVERHEAD CRANE SYSTEM BASED ON PID AND FUZZY SLIDING MODE CONTROL

The paper presents a PID – Fuzzy Sliding Mode control (PID-FSMC) algorithm for overhead crane system to guarantee anti-sway trajectory tracking of the nominal plant. The proposed PID-FSMC law guarantees the closed-loop asymptotical stability as well as improveS the transient response of the load sway dynamics when the trolley is moving. The simulation results confirm the propriety of the proposed controller and show great promise of the controller application in practice

Efficient control of a nonlinear double-pendulum overhead crane with sensorless payload motion using an improved PSO-tuned PID controller

This paper proposes an efficient PID control of a highly nonlinear double-pendulum overhead crane without the need for a payload motion feedback signal. Optimal parameters of the PID controllers are tuned by using an improved particle swarm optimisation (PSO) algorithm based on vertical distance oscillations and potential energy of the crane. In contrast to a commonly used PSO algorithm based on a horizontal distance, the approach resulted in an efficient performance with a less complex controller. To test the effectiveness of the approach, extensive simulations are carried out under various crane operating conditions involving different payload masses and cable lengths. Simulation results show that the proposed controller is superior with a better trolley position response, and lower hook and payload oscillations as compared to the previously developed PSO-tuned PID controller. In addition, the controller provides a satisfactory performance without the need for a payload motion feedback signal

Real-Time Motion Compensation in Ship-to-Ship Load Handling

DoktorgradsavhandlingLike the automotive industry, the maritime industry is facing a higher demand for autonomous offshore operations. It is therefore in the author’s belief that the marine industry has to develop and implement new technology for both existing and new products to meet the increased autonomy demand. This thesis aims at presenting a unified understanding of the motions and the accompanying load handling issue in ship-to-ship operations. The ship-to-ship kinematics is modeled and a crane operator assistant is developed as a possible solution to increase the so-called weather window of ship-to-ship load transfers. The weather window is today determined by the significant wave height, and the current limitation of such operations is at 2.5m significant wave height. Proposing new methods capable of assisting the crane operator when transferring the load from one ship onto another is believed to further relax the weather window criteria, as well as increasing both the safety and efficiency of the operation itself. A novel ship-to-ship estimation algorithm using the well known Extended Kalman Filter (EKF) is developed and experimentally investigated in the Norwegian Motion Laboratory. In addition to the ship-to-ship observer, an observer for measuring the suspended load motions is developed. These estimators are used to form the novel crane operator assistant presented at the end of this thesis. The presented assistant consists of a wire-length assistant and an anti-swing assistant, which both aim at assisting the crane operator in ship-to-ship load transfers by adjusting the crane operator inputs slightly in real-time. The expected outcome is increased repeatability and efficiency, as well as reduced risk in general. The developed methods are described using a common and consistent mathematical notation for both the observers and the kinematic control systems. The appended papers at the end of this thesis have experimentally investigated and validated the proposed methods using several experiments which have been carried out in the Norwegian Motion Laborator

Electronic/electric technology benefits study

The benefits and payoffs of advanced electronic/electric technologies were investigated for three types of aircraft. The technologies, evaluated in each of the three airplanes, included advanced flight controls, advanced secondary power, advanced avionic complements, new cockpit displays, and advanced air traffic control techniques. For the advanced flight controls, the near term considered relaxed static stability (RSS) with mechanical backup. The far term considered an advanced fly by wire system for a longitudinally unstable airplane. In the case of the secondary power systems, trades were made in two steps: in the near term, engine bleed was eliminated; in the far term bleed air, air plus hydraulics were eliminated. Using three commercial aircraft, in the 150, 350, and 700 passenger range, the technology value and pay-offs were quantified, with emphasis on the fiscal benefits. Weight reductions deriving from fuel saving and other system improvements were identified and the weight savings were cycled for their impact on TOGW (takeoff gross weight) and upon the performance of the airframes/engines. Maintenance, reliability, and logistic support were the other criteria

The 15th Aerospace Mechanisms Symposium

Technological areas covered include: aerospace propulsion; aerodynamic devices; crew safety; space vehicle control; spacecraft deployment, positioning, and pointing; deployable antennas/reflectors; and large space structures. Devices for payload deployment, payload retention, and crew extravehicular activities on the space shuttle orbiter are also described

Cumulative Index to NASA Tech Briefs, 1963 - 1966

Cumulative index of NASA Tech Briefs dealing with electrical and electronic, physical science and energy sources, materials and chemistry, life science, and mechanical innovation

Proceedings of the 8th Annual Summer Conference: NASA/USRA Advanced Design Program

Papers presented at the 8th Annual Summer Conference are categorized as Space Projects and Aeronautics projects. Topics covered include: Systematic Propulsion Optimization Tools (SPOT), Assured Crew Return Vehicle Post Landing Configuration Design and Test, Autonomous Support for Microorganism Research in Space, Bioregenerative System Components for Microgravity, The Extended Mission Rover (EMR), Planetary Surface Exploration MESUR/Autonomous Lunar Rover, Automation of Closed Environments in Space for Human Comfort and Safety, Walking Robot Design, Extraterrestrial Surface Propulsion Systems, The Design of Four Hypersonic Reconnaissance Aircraft, Design of a Refueling Tanker Delivering Liquid Hydrogen, The Design of a Long-Range Megatransport Aircraft, and Solar Powered Multipurpose Remotely Powered Aircraft

Advanced Strategies for Robot Manipulators

Amongst the robotic systems, robot manipulators have proven themselves to be of increasing importance and are widely adopted to substitute for human in repetitive and/or hazardous tasks. Modern manipulators are designed complicatedly and need to do more precise, crucial and critical tasks. So, the simple traditional control methods cannot be efficient, and advanced control strategies with considering special constraints are needed to establish. In spite of the fact that groundbreaking researches have been carried out in this realm until now, there are still many novel aspects which have to be explored