0000000000377018
AUTHOR
Morten Ottestad
Improving Separation of Oil and Water With a Novel Coalescing Centrifugal Pump
Summary A novel centrifugal pump that increases oil-droplet sizes in produced water has been developed. This paper investigates a concept of pumping-pressure optimization, with respect to downstream separation efficiency, for the new pump. The investigation shows that the coalescing centrifugal pump always increased the separation efficiency of a downstream hydrocyclone. Furthermore, it is shown that the pumping pressure can be adjusted to maximize the improvement. Experimental results demonstrate how pumping conditions that minimize the volume fraction of droplets with a diameter smaller than the cut size of the hydrocyclone maximize the separation efficiency. Finally, it is demonstrated h…
Teaching Motion Control in Mechatronics Education Using an Open Framework Based on the Elevator Model
Universities and other educational institutions may find it difficult to afford the cost of obtaining cutting-edge teaching resources. This study introduces the adoption of a novel open prototyping framework in the context of mechatronics education, employing low-cost commercial off-the-shelf (COTS) components and tools for the motion control module. The goal of this study is to propose a novel structure for the motion control module in the engineering mechatronics curriculum. The objective is to foster a new teaching method. From a methodology perspective, students are involved in a series of well-organised theoretical lectures as well as practical, very engaging group projects in the lab.…
Experimental validation of a quaternion-based attitude estimation with direct input to a quadcopter control system
This paper presents a method to calculate the attitude quaternion of a quadcopter with few calculations. The quaternion calculation is based on accelerometers and gyroscopes from an Inertial Measurement Unit (IMU). The quaternion from the accelerometer is calculated as the shortest rotation arc from the gravity vector in the navigation frame. The quaternion from the gyroscope is calculated based on equations of the quaternion derivative. A complementary filter is combining the two quaternions with a componentwise comparison. The attitude estimation is calculated without any trigonometric functions. The quaternion is directly used as an input to the attitude controller. The attitude controll…
Automatic Operation and Control of a Novel Coalescing Centrifugal Pump for Improved Oil/Water Separation
Summary In this paper we present the development and implementation of automatic operation and control for a pump/hydrocyclone produced-water-treatment system to maximize oil/water-separation efficiency. A so-called perturb-and-observe (P&O) algorithm is adapted for a novel centrifugal pump to continuously optimize the point of operation. The novel pump coalesces and increases the size of oil droplets in the produced water, resulting in a unique relationship between the coalescing effect and the point of operation, and allowing for the successful implementation of the P&O algorithm. The algorithm was implemented in two different setups, one measuring the droplet-size distribution be…
Robust adaptive backstepping control design for a Nonlinear Hydraulic-Mechanical System
The complex dynamics that characterize hydraulic systems make it difficult for the control design to achieve prescribed goals in an efficient manner. In this paper, we present the design and analysis of a robust nonlinear controller for a Nonlinear Hydraulic-Mechanical (NHM) System. The system consists of an electrohydraulic servo valve and two hydraulic cylinders. Specifically, by considering a part of the dynamics of the NHM system as a norm-bounded uncertainty, two adaptive controllers are developed based on the backstepping technique that ensure the tracking error signals asymptotically converge to zero despite the uncertainties in the system according to the Barbalat lemma. The resulti…
Variable Step Size P&O Algorithms for Coalescing Pump/Deoiling Hydrocyclone Produced Water Treatment System
This paper presents three variable step size P&O algorithms for optimizing the separation efficiency of a coalescing pump/deoiling hydrocyclone produced water treatment system. By continuously adjusting the pumping pressure, and subsequently the coalescing effect, the algorithms are used to minimize the oil concentration downstream the hydrocyclone. Due to the variable step size, the algorithms react rapidly to changes in the upstream produced water characteristics, at the same time as they reduce (or eliminate) steady-state oscillations. Based on both simulation and experimental testing, the study discusses advantages and disadvantages of the algorithms.
Multicopter UAV design optimization
Designing and selecting hardware for a multirotor can be challenging in order to get the best flight performance out of the system. In addition to selecting the hardware, the number of actuators can also be altered. For a 4 actuator (quadrotor) setup, one set of hardware can give the optimal design, while for a 6 actuator setup (hexarotor) the same hardware may not necessarily give the same response. In this paper we present a design optimization process of a multirotor, where the hardware is selected from a set of low-cost off-the-shelf standard RC hobby parts. Constraining the problem to a given hardware ensures existence of the selected hardware, and the design can be implemented. Also t…
Investigating the User Experience of Virtual Reality Rehabilitation Solution for Biomechatronics Laboratory and Home Environment
Virtual reality (VR) technology is a promising tool in physical rehabilitation. Research indicates that VR-supported rehabilitation is beneficial for task-specific training, multi-sensory feedback, diversified rehabilitation tasks, and patient motivation. Our first goal was to create a biomechatronics laboratory with a VR setup for increasing immersion and a motion platform to provide realistic feedback to patients. The second goal was to investigate possibilities to replicate features of the biomechatronics laboratory in a home-based training system using commercially available components. The laboratory comprises of a motion platform with 6-degrees-of-freedom (Rexroth eMotion), fitted wit…
Design and Implementation of Mechatronics Home Lab for Undergraduate Mechatronics Teaching
Author's accepted manuscript © 2022 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. The field of mechatronics is a multidisciplinary field of engineering, where the combination of physical components and theory from several engineering fields is applied to build complex machines. Mechatronics education is an active learning process through practical laboratory exercis…
Improving Separation of Oil and Water Using a Novel Coalescing Centrifugal Pump
Abstract A novel centrifugal pump, which increases oil droplet sizes in produced water, has been developed. This paper investigates a concept of pumping pressure optimization with respect to downstream separation efficiency, for the new pump. The investigation shows that the coalescing centrifugal pump always increases the separation efficiency of a downstream hydrocyclone. Furthermore, it is seen that the pumping pressure can be adjusted to maximize the improvement. Experimental results demonstrate how pumping conditions, which minimize the volume fraction of droplets with a diameter smaller than the cut size of the hydrocyclone, maximize the separation efficiency. Finally, it is exemplifi…
Data gathering and mathematical modelling for pitch stabilisation of a high speed catamaran
This paper deals with the data gathering phase for a 21-foot long planing catamaran. The boat experiences a take-off phenomenon at high speed which needs to be countered. An overview of stability problems in high speed hydroplanes is described with possible solutions recommended. A subsequent gathering of data using laser scanning and computational fluid dynamics (CFD) analysis of the boat are described. The paper ends with a look at the initial developments of stabilising systems for the boat.
Experimental study on the influence of controller firmware on multirotor actuator dynamics
In this paper the dynamic response of a propeller actuator commonly used in hobby unmanned aerial vehicles is studied experimentally. It is shown that the choice of electronic speed controller firmware has a significant effect on the overall actuator dynamics. Six different scenarios are tested: 1+2) Rising/falling step response with the standard firmware of the Hobbyking F30a, 3+4) Rising/falling step response with firmware from Simon Kirby/GitHub and 5+6) Rising/falling step response with firmware from Simon Kirby/GitHub including complementary Pulse-Width-Modulation (PWM) switching. Experimental results show a significant difference in actuator dynamics depending on the chosen firmware. …