59 research outputs found
Concept and modelling of the electrohydraulic valve with DC and stepper motors
No full textThe article describes concept and modelling of a new type of electrohydraulic valve controlled by the combination of a stepper motor and a DC motor. The aim of this invention is to use in the proportional valve two motors with the different properties. Both motors are responsible for the movement of a valve spool. The stepper motor and the DC motor are connected to a shaft by using a bellows coupling. Transfer from rotary to linear motion is performed by use of a bolt-nut system. According to the invention, presented here valve can be used in hydraulic drive systems with high positioning accuracy requirement. The author was granted a patent no. P.421994 on the invention described in this paper
Application of the MEMS Accelerometer as the Position Sensor in Linear Electrohydraulic Drive
No full textVarious distance sensors are used as measuring elements for positioning linear electrohydraulic drives. The most common are magnetostrictive transducers or linear variable differential transformer (LVDT) sensors mounted inside the cylinder. The displacement of the actuator’s piston rod is proportional to the change in the value of the current or voltage at the output from the sensor. They are characterized by relatively low measurement noise. The disadvantage of presented sensors is the need to mount them inside the cylinders and the high price. The article presents preliminary research on the replacement of following sensors and the use of a microelectromechanical system (MEMS) accelerometer as a measuring element in the electrohydraulic drive control system. The control consisted of two phases: at first, the signal from the acceleration sensor was analyzed during the actuator movement, based on the value determined from the simplified model implemented on the controller. In the range of motion in which the dynamics were the lowest, the signal was integrated and the obtained value was used in the second phase of motion. In the correction phase, a new set point was determined. Conducting the research required building a dedicated research stand. The author conducted the simulation and experimental research
Use of the fractional order PD controller in electro-hydraulic drive
No full textThis paper presents initial research on use of the fractional order PD controller of the electro-hydraulic drive – step response in open and close loop. Test stand built based on hydraulic cylinder combined with electro-hydraulic servo valve. Control system based on PLC with touch panel. Experimental investigation is performed for different coefficient of fractional PD regulator. The aim was to check power of s denominator changes impact in PD controller. Performed test stand allowed to conduct further comprehensive investigations use of the fractional order controller in electro-hydraulic drives.W artykule opisano wstępne badania dotyczące zastosowania regulatora niecałkowitego rzędu w napędzie elektrohydraulicznym. Jako obiekt badań posłużył siłownik hydrauliczny połączony z serwozaworem. Układ sterowania zbudowano w oparciu o sterownik PLC z panelem dotykowym. Napęd poddano testom z zamkniętą i otwartą pętlą sprzężenia zwrotnego. Przebadano wpływ zmiany wartości poszczególnych parametrów regulatora niecałkowitego rzędu, w tym stopnia części różniczkującej
Investigations of Electronic Controller for Electrohydraulic Valve with DC and Stepper Motor
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Author Correction: The effect of national protest in Ecuador on PM pollution (Scientific Reports, (2021), 11, 1, (17591), 10.1038/s41598-021-96868-6)
No full textIn the original version of this Article Rasa Zalakeviciute, Katiuska Alexandrino, Danilo Mejia, Marco G. Bastidas, Nora H. Oleas, Diana Gabela, Phuong Ngoc Chau, Santiago Bonilla-Bedoya & Yves Rybarczyk were incorrectly affiliated with ‘Secretariat of the Environment, Quito, Ecuador’. In addition, Valeria Diaz was incorrectly affiliated with ‘Research Center for the Territory and Sustainable Habitat, Universidad Tecnológica Indoamérica, Machala y Sabanilla, 170301, Quito, Ecuador’. The correct affiliations are listed below: 1. Grupo de Biodiversidad Medio Ambiente y Salud (BIOMAS), Universidad de Las Américas, calle José Queri y Av. de los Granados / Bloque 7, 170125, Quito, EC, Ecuador Rasa Zalakeviciute, Katiuska Alexandrino, Marco G. Bastidas & Diana Gabela 2. Facultad de Ciencias Químicas de La Universidad de Cuenca, Cuenca, Ecuador Danilo Mejia 3. Centro de Estudios Ambientales (CEA) de la Universidad de Cuenca, Cuenca, Ecuador Danilo Mejia 4. Centro de Investigación de la Biodiversidad y Cambio Climático (BioCamb) e Ingeniería en Biodiversidad y Recursos Genéticos, Facultad de Ciencias de Medio Ambiente, Universidad Tecnológica Indoamérica, Machala y Sabanilla, 170301, Quito, EC, Ecuador Nora H. Oleas 5. Faculty of Data and Information Sciences, Dalarna University, 791 88, Falun, Sweden Phuong Ngoc Chau & Yves Rybarczyk 6. Research Center for the Territory and Sustainable Habitat, Universidad Tecnológica Indoamérica, Machala y Sabanilla, 170301, Quito, Ecuador Santiago Bonilla-Bedoya 7. Secretariat of the Environment, Quito, Ecuador Valeria Diaz The original Article has been corrected
Electrohydraulic Drive with a Flow Valve Controlled by a Permanent Magnet Synchronous Motor
No full textThis article presents an electrohydraulic drive with a new electrohydraulic flow valve controlled by a Permanent Magnet Synchronous Motor (PMSM), designed and built by the authors. In comparison to a valve with a proportional electromagnet, the use of a PMSM has enabled significant improvements in the key characteristics of the valve. A theoretical framework and a model of a PMSM are presented; subsequently, a valve with this motor is proposed and tested. Step responses of the real valve and its static and frequency characteristics are measured. The characteristics obtained in the simulation are compared with those obtained in the laboratory investigations, showing their good compliance. The obtained characteristics of the new valve are better than those of a typical proportional valve. The new valve is applied in an electrohydraulic linear actuator. For positioning tasks, two types of controllers are applied and compared: a proportional-derivative controller and a fractional order proportional-derivative controller showing satisfactory parameters
A Comparative Study of Different Fingertips on the Object Pulling Forces in Robotic Gripper Jaws
No full textThis paper presents a comparative study of the use of different fingertips in robotic gripper jaws with respect to measuring the pulling force of selected shaped objects from their grasp. The authors built a dedicated test stand and provided methodology to evaluate it. The authors’ innovative approach was to design accessory-controlled jaws for the base of the Robotiq 2F-140 gripper. For the study, rigid structures—flexible soft cushions filled with air and magnetorheological fluid (MRF)—were developed for the jaw. In this way, comparable measurement results were obtained in terms of the structure of the gripper set-up. The secondary purpose of the study was to demonstrate the potential of the soft cushions that are adaptable to the shape of a gripped object. As a result, an adaptive structure was obtained that allows object pulling forces that are comparable to rigid fingertips. In doing so, this does not damage the surface of any of the interacting components. The cushions were made of thermoplastic polyurethane (TPU) formed using 3D printing technology. The results obtained during the implementation of this research may be beneficial for comparing gripper capabilities; thus, they can contribute to advances in smart devices and many industrial fields, including robotics and bioengineering
Development of a Speech System Using BCI Based on ERD/ERS for Patients Suffering from Amyotrophic Lateral Sclerosis
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