Motion compensated offshore knuckle boom crane: A mechanical feasibility study

To overcome the problem of wave-induced vessel motions on the crane tip, technologies have been developed to compensate for these motions. Most vessels nowadays, are equipped with dynamic positioning systems, these systems reduce the yaw, surge and sway movement of the vessel. This leaves, the motions roll, pitch and heave uncompensated. To...

Realtime Data-driven Learning and Model Predictive Control using Gaussian Processes for Dynamical Systems

Nowadays, machine learning (ML) methods rapidly evolve for their use in model-based control applications. Model-based control requires an accurate model description of the dynamical system to reassure the performance of the controller. Conventionally, this model description is retrieved from first-principles modelling which can be problematic if...

Identification of a dynamic center line model and its implementation in FLORIDyn: A comparison between MOESP and DMDc system identification

Wind energy plays an essential role in the transition to a sustainable future and wind turbines allow us to utilize it. Wind turbines are often installed in close proximity to make the best use of the given space and to save costs. This also has the disadvantage that the turbines influence each other due to wakes. This is where wind farm control...

Experimental Closed-Loop Excitation of Nonlinear Normal Modes on an Elastic Industrial Robot

Adding elastic elements to the mechanical structure should enable robots to perform efficient oscillatory tasks. Still, even characterizing natural oscillations in nonlinear systems is a challenge in itself, which nonlinear modal theory promises to solve. Therein eigenmanifolds generalize eigenspaces to mechanical systems with non-Euclidean...

Feedback Regulation of Elastically Decoupled Underactuated Soft Robots

The intrinsically underactuated and nonlinear nature of continuum soft robots makes the derivation of provably stable feedback control laws a challenging task. Most of the works so far circumvented the issue either by looking at coarse fully-actuated approximations of the dynamics or by imposing quasi-static assumptions. In this letter, we...

Dynamics of an Organic Rankine Cycle for OTEC: Performance analysis of the transient regions

The global energy demand is growing, while climate change is demanding a sustainable way of generating this energy. Ocean Thermal Energy Conversion (OTEC) can be a part of the solution for this problem. OTEC generates electricity by using the temperature difference between the surface water of the ocean and the water at 1000 meters depth as a...

Challenges and solutions for sensor-based incremental nonlinear control of hydraulically actuated parallel robots

Incremental Nonlinear Dynamic Inversion has shown increases in performance and robustness to model mismatches and uncertainties in hydraulic control as compared to other model-based controllers. This work will expand on hydraulic Incremental Nonlinear Dynamic Inversion force control and discuss three of its challenges and accompanying solutions....

Design and characterization of variable stiffness structural joints

This paper presents design and characterization of a new type of structural joint which can vary its stiffness through actuation. Stiffness variation is employed to control the dynamic response of frame structures equipped with such joints. The joint is made of a shape memory polymer (SMP) core which is reinforced by an SMP-aramid composite...

Integrated Control System for Frequency and Voltage Support via Type-3 Wind Turbines equipped with Energy Storage System

During previous centuries, humanity had relied on fossil fuels to generate the demanded energy. Nowadays, the extensive use of oil, gas and coal for energy production is becoming a major problem which concerns modern society. Global warming and climate change are the biggest challenges the scientific community has faced. The main factor which...

Robust Non-linear Control for Winged Re-entry Vehicles: Analysis of Control Concepts

An analysis of attitude controller concepts, including four attitude flight controllers, for the re-entry of the HORUS-2b. The four concerning attitude flight controller concepts are the benchmark Linear Quadratic Regulator (LQR), Model predictive Controller, Incremental Non-linear Dynamic Inversion (INDI) and Sliding Mode Controller. Each...

Multibody Approach to Controlled Removal of Large Space Debris with Flexible Appendages

The space environment is ever-changing with space structures getting larger and the orbits getting increasingly crowded with time. This creates a need for removal of large defunct satellites to avoid the disastrous Kessler syndrome, which poses a major threat to the future of space exploration. This research examines the dynamics and control...

Propulsion System Effects on the Controllability of a Second-Stage Spaceplane

Spaceplanes are the future of space travel and launching objects into space. They are fully reusable, and provide a lot of flexibility to a mission. This thesis focuses on the propulsion system and its impact on the stability and control of a spaceplane. The main research question is: "Which parameters and deficiencies in the propulsion system...

Attitude modeling of the DelftaCopter: a system identification approach

Previous years have seen a rise in the use of Unmanned Aerial Vehicles (UAVs). Reaching a large endurance and range while being able to perform Vertical Take-Off and Landing (VTOL) landings allows a broad range of applications. For this purpose the DelftaCopter (DC) was developed, a tilt-body tailsitter UAV. It hovers using a single helicopter...

Optimal design of circular baffles on sloshing in a rectangular tank horizontally coupled by structure

Parametric studies on the optimization of baffles on vibration suppression of partially filled tanks coupled by structure have been widely conducted in literature. However, few studies focus on the effect of the position of the baffles on fluid flow stratification and dampening the motion. In the present study, a numerical investigation, an...

Vehicle-class Specific Control of Freeway Traffic

The increase of mobility of the past decades has led to substantial congestion on the freeways. Traffic jams emerge both on a daily basis at the same location, as well as during accidents when a part of the freeways is temporarily blocked. In those cases, traffic management centers intervene into traffic in order to reduce or even dissolve...