Morten Ottestad

• Sanfilippo, Filippo; Økter, Martin Bjaadal; Dale, Jørgen; Hua, Minh Tuan & Ottestad, Morten (2024). Revolutionising Prosthetics and Orthotics with Affordable Customisable Open-Source Elastic Actuators. In NN, . (Eds.), International Conference on Automation, Robotics and Applications (ICARA). Institute of Electrical and Electronics Engineers (IEEE). ISSN 9798350394252. p. 57–63. doi: 10.1109/ICARA60736.2024.10553120. Full text in Research Archive Show summary

  Collaborative robots, also known as cobots, have become progressively popular as they are designed to safely work alongside humans or in shared environments. The adoption of compliant actuators, which avoid damage in the event of an unintentional collision, is an important feature of their design. In prosthetic and orthotic applications, the use of compliant actuators, which minimise damage in the case of an inadvertent contact, is critical to ensuring safety and comfort for the user. In dynamic settings, elastic actuators are preferred over rigid ones, however most compliant cobots are currently too expensive or complex to construct for prosthetic and orthotic applications. To address this challenge, this study presents a low-cost sensorised elastic actuator design for prosthetics and orthotics. This is presented as an educational framework. The design is modular and can be quickly customised using 3D printing technology, allowing for efficient and cost-effective fabrication. Both the hardware and software are open-source, enabling easy access for students, researchers and practitioners. The design also allows for the introduction of impedance and admittance control techniques, providing even greater versatility to the system.

• Sanfilippo, Filippo; Økter, Martin Bjaadal; Dale, Jørgen; Hua, Minh Tuan; Zafar, Muhammad Hamza & Ottestad, Morten (2024). Open-source design of low-cost sensorised elastic actuators for collaborative prosthetics and orthotics. HardwareX. 19. doi: 10.1016/j.ohx.2024.e00564. Full text in Research Archive
• Górski, Filip; Łabudzki, Remigiusz; Żukowska, Magdalena; Sanfilippo, Filippo; Ottestad, Morten & Zelenay, Martin [Show all 8 contributors for this article] (2023). Experimental Evaluation of Extended Reality Technologies in the Development of Individualized Three-Dimensionally Printed Upper Limb Prostheses. Applied Sciences. 13(14). doi: 10.3390/app13148035. Full text in Research Archive Show summary

  This paper presents results from experimental studies that assess the utilization of virtual, augmented, and mixed reality (VR, AR, MR) at different stages of developing personalized 3D printed upper limb prostheses for adult patients. The prostheses are designed automatically using the AutoMedPrint system, leveraging 3D scans as described in various prior publications. Various stages of development of the prosthesis are made as applications of different extended reality technologies. An assembly instruction is implemented as an immersive VR application, a configurator is designed as AR application and a configurator and try-on application is prepared and deployed in MR. The applications are tested by an international group of experts during a scheduled experiment. The experts then participate to surveys and comparatively evaluate the potential of all the XR technologies. The paper presents the development of these applications, provides a detailed account of the experimental process, including the rankings of XR technologies for different applications throughout the lifecycle of a prosthetic device.

• Borge, Jørgen; Wad, Martin Sauar; Økter, Martin Bjaadal; Ottestad, Morten; Rudolfsen, Morten H. & Zhou, Jing (2022). Design and Implementation of Mechatronics Home Lab for Undergraduate Mechatronics Teaching, 2022 IEEE 17th International Conference on Control & Automation (ICCA). IEEE (Institute of Electrical and Electronics Engineers). ISSN 9781665495721. p. 291–296. doi: 10.1109/ICCA54724.2022.9831876. Full text in Research Archive Show summary

  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 exercises and problem-based learning. This paper presents the design and implementation of a mechatronics home lab to support undergraduate mechatronics teaching. The purpose is to support theoretical teaching in mechatronics with a low-cost, 3D-printable platform where the students can experiment and practice instrumentation and control theory with a practical problem-based approach. Five projects were introduced for experiment implementation of the developed home lab. Throughout these experiments, it is intended to facilitate the understanding of theories and concepts in mechatronics, and enhance the ability to design and implementation of experiments, the collection and analysis of data, and the conducting of simulation in MATLAB.

• Sanfilippo, Filippo; Økter, Martin Bjaadal; Eie, Tine Cecilia & Ottestad, Morten (2022). An Open Framework for teaching Motion Control for Mechatronics Education, 2022 7th International STEM Education Conference (iSTEM-Ed). IEEE (Institute of Electrical and Electronics Engineers). ISSN 9781665498210. doi: 10.1109/iSTEM-Ed55321.2022.9920788. Full text in Research Archive Show summary

  This paper proposes the introduction of a novel open prototyping framework that involves using low-cost commercial off-the-shelf (COTS) components and tools for the module of motion control, within mechatronics education. The goal of this study is to propose a novel structure for the motion control module in the engineering mechatronics curriculum. This is accomplished by integrating students in a series of well-organised theoretical lectures as well as hands-on, highly engaging labora-tory group projects. Surface learning parts and deep learning sections are combined frequently to encourage learners to grasp, make connections, and expand their knowledge. The structure of the course as well as the key topics are discussed. The proposed open framework, which consist of an elevator model, is presented in details.

• Sanfilippo, Filippo; Økter, Martin Bjaadal; Eie, Tine Cecilia & Ottestad, Morten (2022). Teaching Motion Control in Mechatronics Education Using an Open Framework Based on the Elevator Model. Machines. 10(10). doi: 10.3390/machines10100945. Full text in Research Archive Show summary

  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. To help students understand, draw connections, and broaden their knowledge, the methods of surface learning and deep learning are frequently mixed thoroughly. The structure of the course as well as the key topics are discussed. The proposed open framework, which consists of an elevator model, is presented in details. Students’ early evaluation indicates that the course organisation and subjects are successful and beneficial.

• Madshaven, Julie Madelen; Markseth, Tonje Fjeldstad; Jomås, David Bye; Isabwe, Ghislain Maurice Norbert; Ottestad, Morten & Reichert, Frank [Show all 7 contributors for this article] (2021). Investigating the User Experience of Virtual Reality Rehabilitation Solution for Biomechatronics Laboratory and Home Environment. Frontiers in Virtual Reality. 2. doi: 10.3389/frvir.2021.645042. Full text in Research Archive
• Husveg, Rune; Husveg, Trygve; Teeffelen, Teeffelen van; Ottestad, Morten & Hansen, Michael Rygaard (2020). Variable step size p&o algorithms for coalescing pump/deoiling hydrocyclone produced water treatment system. MIC Journal: Modeling, Identification and Control. ISSN 0332-7353. 41(1), p. 13–27. doi: 10.4173/MIC.2020.1.2. Full text in Research Archive
• Husveg, Rune; Husveg, Trygve; Teeffelen, Niels van; Ottestad, Morten & Hansen, Michael Rygaard (2019). Automatic operation and control of a novel coalescing centrifugal pump for improved oil/water separation. SPE Production & Operations. ISSN 1930-1855. 34(3), p. 508–519. doi: 10.2118/195591-PA. Full text in Research Archive
• Husveg, Rune; Husveg, Trygve; Teeffelen, Niels van; Ottestad, Morten & Hansen, Michael Rygaard (2018). Improving Separation of Oil and Water With a Novel Coalescing Centrifugal Pump. SPE Production & Operations. ISSN 1930-1855. 33(04), p. 857–865. doi: 10.2118/188772-PA. Full text in Research Archive
• Husveg, Rune; Husveg, Trygve; Teeffelen, Niels van; Ottestad, Morten & Hansen, Michael Rygaard (2017). Improving Separation of Oil and Water Using a Novel Coalescing Centrifugal Pump, SPE Abu Dhabi International Petroleum Exhibition & Conference. Society of Petroleum Engineers. ISSN 9781613995631. doi: 10.2118/188772-MS. Full text in Research Archive
• Magnussen, Øyvind; Ottestad, Morten & Hovland, Geir Edvin (2015). Multicopter design optimization and validation. MIC Journal: Modeling, Identification and Control. ISSN 0332-7353. 36(2), p. 67–79. doi: 10.4173/mic.2015.2.1. Full text in Research Archive
• Magnussen, Øyvind; Hovland, Geir; Ottestad, Morten & Kirby, Simon (2014). Experimental Study on the Influence of Controller Firmware on Multirotor Actuator Dynamics. In NN, NN (Eds.), 2014 IEEE International Symposium on Robotic and Sensors Environments (ROSE). Curran Associates, Inc.. ISSN 9781479949250. doi: 10.1109/ROSE.2014.6952992. Full text in Research Archive
• Magnussen, Øyvind; Hovland, Geir & Ottestad, Morten (2014). Multicopter UAV Design Optimization, 2014 IEEE/ASME 10th International Conference on Mechatronic and Embedded Systems and Applications(MESA). IEEE (Institute of Electrical and Electronics Engineers). ISSN 9781479922802. doi: 10.1109/MESA.2014.6935598. Full text in Research Archive
• Magnussen, Øyvind; Ottestad, Morten & Hovland, Geir (2013). Experimental Validation of a Quaternion-based Attitude estimation with Direct Input to a Quadcopter Control System, Unmanned Aircraft Systems (ICUAS), 2013 International Conference On. IEEE (Institute of Electrical and Electronics Engineers). ISSN 9781479908172. p. 480–485. doi: 10.1109/ICUAS.2013.6564723. Full text in Research Archive Show summary

  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 controller is a PD controller running at 400Hz. A model of the quadcopter in Matlab verified that the control system worked as intended. The estimator was verified with a Stewart platform, by mounting the quadcopter on top of it and comparing the angles from the Stewart platform with the angles from the filter. Finally the algorithms were implemented on a quadcopter controller board, and the attitude estimator were compared with the attitude estimation from a high-end IMU from MicroStrain. The complete control system was also tested on a 8-bit microcontroller running at 16 MHz. The relatively slow processor on the microcontroller was also able to do every calculations within 2.5ms.

• Ottestad, Morten; Nilsen, Nicolai & Hansen, Michael Rygaard (2012). Reducing the Static Friction in Hydraulic Cylinders by Maintaining Relative Velocity Between Piston and Cylinder, 2012 12th International Conference on Control, Automation and Systems, Proceedings. IEEE (Institute of Electrical and Electronics Engineers). ISSN 9788993215045. p. 764–769. Full text in Research Archive Show summary

  This paper is concerned with friction in hydraulic cylinders and it’s influence on the performance of hydralically actuated system. A method for the elimination of stiction in hydraulic cylinders is presented and experimentally verified. The method utilizes the rotational degree of freedom between the piston and the cylinder to add relative velocity at the contact surfaces between piston and cylinder when the main axial motion is zero. For modeling purposes an augmentation of the Stribeck friction force equation is introduced that reflects the influence of the added motion. The possible impact of stiction elimination on the performance of heave compensation equipment is discussed and examplified via time domain simulations.

• Ottestad, Morten; Nilsen, Nico & Hansen, Michael Rygaard (2011). A Method for Friction Control in Hydraulic Cylinders. In Singh, Maneesh; N., Rao Raj B. K. & Liyanage, Jayantha Prasanna (Ed.), Proceedings of the 24th International Congress on Condition Monitoring and Diagnostics Engineering Management (COMADEM2011). COMADEM International. ISSN 9780954130725. p. 817–823. Full text in Research Archive Show summary

  This paper is concerned with friction in hydraulic cylinders and its influence on the performance of hydralically actuated system. A method for friction control is presented. The basic idea in the proposed method is that the absolute value of the relative velocity between piston and cylinder rather than just the longitudinal relative velocity determines to what degree the zero-velocity stiction is eliminated. A test rig has been designed that is capable of introducing a rotational motion of the piston without introducing additional shear forces, i.e., via a force couple. The results clearly show that the stiction part of the frictional force is eliminated when the rotational motion is controlled so that it appears simultaneously with zero relative velocity in longitudinal direction. The experimental data has made it possible to develop a friction model that describes the friction in a hydraulic cylinder that covers any combination of longitudinal and rotational relative velocity.

• Gu, Peter; Gundersen, R.; Kalvik, a.o.; Salvesen, r.; Karimi, Hamid Reza & Ottestad, Morten (2011). Data gathering for pitch stabilization of a high speed catamaran. In Macha, E. & Pawliczek, R. (Ed.), MECHATRONIC SYSTEMS AND MATERIALS 2010. Warsaw University of Technology. ISSN 9788360691786. p. 69–80. Full text in Research Archive
• Hansen, Michael Rygaard & Ottestad, Morten (2011). Friction Compensation in Hydraulic Cylinders. In Singh, Maneesh; N., Rao Raj B. K. & Liyanage, Jayantha Prasanna (Ed.), Proceedings of the 24th International Congress on Condition Monitoring and Diagnostics Engineering Management (COMADEM2011). COMADEM International. ISSN 9780954130725. p. 1225–1232. Full text in Research Archive Show summary

  This paper is concerned with friction compensation of hydraulic cylinders. A simplified model of an offshore drilling heave compensator is used as design study. The heave compensator includes the typical characteristics encountered in offshore motion control of hydraulically actuated equipment: wave induced heave motion, friction in one or more main hydraulic cylinders and a combination of fixed and heave motion references. A friction compensation scheme is proposed that estimates a friction force from cylinder travel and velocity feedback. Further, any main cylinder force variations caused by the passive compensation system is included in the active compensation force. The control element is a servohydraulic system consisting of two double acting hydraulic cylinders, a high response servo valve and a constant pressure supply. The servo valve inner position feedback loop is modeled as second order system and the compensation force feedback loop is managed by a PI-controller that computes the spool reference opening from the deviation in reference and actual compensation force. A special purpose time domain simulation model is used to examine the importance of friction estimation and valve bandwidth. A Stribeck function is used to simulate the actual friction of the main hydraulic cylinder.

• Gu, Peter; Gundersen, R.; Kalvik, a.o.; Salvesen, r.; Karimi, Hamid Reza & Ottestad, Morten (2011). Data Gathering and Mathematical Modeling for Pitch Stabilization of a High Speed Catamaran. International journal of Modeling, identification and control. ISSN 1746-6172. 14(3), p. 149–158. doi: 10.1504/ijmic.2011.042651. Full text in Research Archive Show summary

  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.

• Ottestad, Morten; Haland, Kjell Olav & Hansen, Michael Rygaard (2010). A model based approach to design of passive and active heave compensation of crown mounted drilling equipment. Proceedings of the IASTED International Conference on Modelling, Identification, and Control (MIC). ISSN 1025-8973. p. 128–135. Full text in Research Archive Show summary

  The current work is on passive and active heave compensation of offshore drilling equipment. The main purpose of heave compensation while drilling from vessels or semisubmersible platforms is to maintain the drilling operation unaffected by the wave induced motion. Specifically, this paper deals with the problem of bit-lift-off, i.e., the situation where the drillbit looses contact with the formation. The investigated system is of an existing crown mounted compensator and the passive heave compensation scheme is described including the usefulness of force equalizing cylinders. Also, an approach to the design of a controller for the active heave compensation system is put forward that is based on the sensor signals available. A detailed model of the crown mounted compensator is developed that includes mechanics, hydraulics and pneumatics. It is developed in the commercial modeling environment of SimulationX? and used together with a worst case scenario as evaluation tool for the proposed control scheme.

• Choux, Martin; Karimi, Hamid Reza; Hovland, Geir; Hansen, Michael Rygaard; Ottestad, Morten & Blanke, Mogens (2009). Robust Adaptive Backstepping Control Design for a Nonlinear Hydraulic-Mechanical System, Proceedings of the 48th IEEE Conference on Decision and Control, Shanghai. IEEE (Institute of Electrical and Electronics Engineers). ISSN 9781424438723. p. 2460–2467. Full text in Research Archive Show summary

  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 consistes in 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 resulting controllers are able to take into account the interval uncertainties in Coulomb friction parameters and in the internal leakage parameters in the cylinders. Two adaptation laws are obtained by using the Lyapunov functional method and inequality techniques. Simulation results demonstrate the performance and feasibility of the proposed method.

View all works in NVA

• Robbersmyr, Kjell Gunnar & Ottestad, Morten (2018). Mekatronikk. Full text in Research Archive
• Knausgård, Kristian Muri & Ottestad, Morten (2018). Mobile autonome roboter i et utdanningsperspektiv. Full text in Research Archive
• Husveg, Rune; Husveg, Trygve; Teeffelen, Niels van; Ottestad, Morten & Hansen, Michael Rygaard (2017). Improving Separation of Oil and Water Using a Novel Coalescing Centrifugal Pump. Full text in Research Archive
• Husveg, Rune; Husveg, Trygve; Teeffelen, Niels van; Ottestad, Morten & Hansen, Michael Rygaard (2016). Performance of a Coalescing Multistage Centrifugal Produced Water Pump with Respect to Water Characteristics and Point of Operation. Full text in Research Archive

View all works in NVA