Sergiu-Dan Stan

Evolutionary approach to optimal design of 3 DOF translation exoskeleton and medical parallel robots

Parallel robots find many applications in human-systems interaction, medical robots, rehabilitation, exoskeletons, to name a few. These applications are characterized by many imperatives, with robust precision and dynamic workspace computation as the two ultimate ones. This paper presents a multi-objective optimum design procedure to 3 degrees of freedom (DOF) parallel robots with regards to four optimality criteria: workspace boundary, transmission quality index, stiffness. A kinematic optimization was performed to maximize the workspace of the parallel robot. In order to perform an optimal design of 3 DOF parallel robots, an objective function was developed first, and then Genetic Algorithms applied in order to optimize the objective function. The experimental results demonstrate the advantages of the presented optimization procedure in design of 3 DOF parallel robots, specifically TRIGLIDE and DELTA robots. These advantages are reflected in a presented framework for robust, precise, and dynamically calculated workspace boundaries. Therefore, the performances of the 3 DOF translation parallel robots provide high potential and good prospects for their practical implementation in human-systems interaction.

Kinematics analysis, design, and control of an Isoglide3 Parallel Robot (IG3PR)

The paper presents a novel structure of the Isoglide3 parallel robot (IG3PR), as an effective robotic device with three degrees of freedom manipulation. The IG3PR manipulator offers the characteristics, advantageous relative to the other parallel manipulators (light weight construction), while on the other hand alleviates some of the traditional weaknesses of parallel manipulators, (extensive use of spherical joints and coupling of the platform orientation and position). The presented IG3PR robot employs only revolute (rotary) and prismatic (sliding) joints to achieve the translational motion of the moving platform. The pivotal advantages of the presented parallel manipulator are the following: all of the actuators can be attached directly to the base; closed-form solutions are available for the forward and inverse kinematics; and the moving platform maintains the same orientation throughout the entire workspace. In addition to these comparative improvements, the paper presents an innovative user interface for high-level control of the Isoglide3 parallel robot. The novel IG3PR was verified and tested, and results in MATLAB, Simulink, and SimMechanics were presented.

Cloud E-learning for Mechatronics

This paper describes results of the CLEM project, Cloud E-learning for Mechatronics. CLEM is an example of a domain-specific cloud that is especially tuned to the needs of VET (Vocational, Education and Training) teachers. An interesting development has been the creation of remote laboratories in the cloud. Learners can access such laboratories to support their practical learning of mechatronics without the need to set up laboratories at their own institutions. The cloud infrastructure enables multiple laboratories to come together virtually to create an ecosystem for educators and learners. From such a system, educators can pick and mix materials to create suitable courses for their students and the learners can experience different types of devices and laboratories through the cloud. The paper provides an overview of this new cloud-based e-learning approach and presents the results. The paper explains how the use of cloud computing has enabled the development of a new method, showing how a holistic e-learning experience can be obtained through use of static, dynamic and interactive material together with facilities for collaboration and innovation. We have designed and developed a new customized cloud platform for e-learning.We have designed and developed a new cloud framework to model mechatronic devices.We have evaluated the system with users and teachers in the field.The proposed system is the first cloud based e-learning system for mechatronics.

Performance analysis of 3 DOF Delta parallel robot

Parallel robots have inherent advantages for many applications in the fields of robotics. They offer high dynamic capabilities combined with high accuracy and stiffness. There are a lot of performance criteria which have to be taken into account and which are pose dependent. The main idea of this paper is to present the fundamentals for a performance evaluation of the 3 DOF Delta parallel robot. Therefore we discuss a large number of performance criteria dealing with workspace, quality transmission, manipulability, dexterity and stiffness.

A model based predictive control algorithm for building temperature control

The paper presents a model-based predictive control algorithm that uses a limited number of control sequences for on-line simulation of future behaviour of the process. Each control sequence used in simulation generates a predicted sequence of the output signal. The predicted output sequences are analysed and evaluated and then, using a set of rules, the ‘optimal’ control signal is computed. To simulate the future behaviour of the process it is used a process model and also the previous sequences of the input and output signals from the process. The algorithm permits directly use of the nonlinear model of the process. The algorithm is used for simulation of the temperature control in a house and compared with the usual algorithms of type PI.

Kinematics analysis, workspace, design and control of 3-RPS and TRIGLIDE medical parallel robots

Parallel robots find many applications in human-systems interaction, medical robots, rehabilitation, exoskeletons, to name a few. These applications are characterized by many imperatives, with robust precision and dynamic workspace computation as the two ultimate ones. This paper presents kinematic analysis, workspace, design and control to 3 degrees of freedom (DOF) parallel robots. Parallel robots have received considerable attention from both researchers and manufacturers over the past years because of their potential for high stiffness, low inertia and high speed capability. Therefore, the 3 DOF translation parallel robots provide high potential and good prospects for their practical implementation in human-systems interaction.

Platform as a service gateway for the Fog of Things

Abstract Internet of Things (IoT), one of the key research topics in recent years, together with concepts from Fog Computing, brings rapid advancements in Smart City, Monitoring Systems, industrial control, transportation and other fields. These applications require a reconfigurable sensor architecture that can span multiple scenarios, devices and use cases that allow storage, networking and computational resources to be efficiently used on the edge of the network. There are a number of platforms and gateway architectures that have been proposed to manage these components and enable application deployment. These approaches lack horizontal integration between multiple providers as well as higher order functionalities like load balancing and clustering. This is partly due to the strongly coupled nature of the deployed applications, a lack of abstraction of device communication layers as well as a lock-in for communication protocols. This limitation is a major obstacle for the development of a protocol agnostic application environment that allows for single application to be migrated and to work with multiple peripheral devices with varying protocols from different local gateways. This research looks at existing platforms and their shortcomings as well as proposes a messaging based modular gateway platform that enables clustering of gateways and the abstraction of peripheral communication protocol details. These novelties allow applications to send and receive messages regardless of their deployment location and destination device protocol, creating a more uniform development environment. Furthermore, it results in a more streamlined application development and testing while providing more efficient use of the gateway’s resources. Our evaluation of a prototype for the system shows the need for the migration of resources and the QoS advantages of such a system. The examined use case scenarios show that clustering proves to be an advantage in certain use cases as well as presenting the deployment of a larger testing and control environment through the platform.

Multi-objective Design Optimization of Mini Parallel Robots Using Genetic Algorithms

This paper is aimed at presenting a study on the optimization of the Biglide and Bipod mini parallel robots, which comprises two-degree-of-freedom (DOF) mini parallel robots with constant and variable struts. The robot workspace is characterized and the inverse kinematics equation is obtained. In the paper, design optimization is implemented with Genetic Algorithms (GA) for optimization considering transmission quality index, design space and workspace. Here, intended to show the advantages of using the GA, we applied it to a multicriteria optimization problem of 2 DOF mini parallel robots. Genetic algorithms (GA) are so far generally the best and most robust kind of evolutionary algorithms. A GA has a number of advantages. It can quickly scan a vast solution set. Bad proposals do not affect the end solution negatively as they are simply discarded. The obtained results have shown that the use of GA in such kind of optimization problem enhances the quality of the optimization outcome, providing a better and more realistic support for the decision maker.

Optimal Design of a 2 DOF Micro Parallel Robot Using Genetic Algorithms

This paper is aimed at presenting a study on the optimization of the Biglide micro parallel robot, which comprises two-degree-of-freedom (DOF) micro parallel robot with constant struts. The robot workspace is characterized and the inverse kinematics equation is obtained. In the paper, design optimization is implemented with Genetic Algorithms (GA) for optimization considering transmission quality index, design space and workspace. Here, intended to show the advantages of using the GA, we applied it to a multicriteria optimization problem of 2 DOF micro parallel robot. Genetic algorithms (GA) are so far generally the best and most robust kind of evolutionary algorithms. A GA has a number of advantages. It can quickly scan a vast solution set. Bad proposals do not affect the end solution negatively as they are simply discarded. The obtained results have shown that the use of GA in such kind of optimization problem enhances the quality of the optimization outcome, providing a better and more realistic support for the decision maker.

Genetic Algorithms Multiobjective Optimization of a 2 DOF Micro Parallel Robot

This paper is aimed at presenting a study on the optimization of the Bipod micro parallel robot, which comprises a two-degree-of-freedom (DOF) micro parallel robot with variable struts. The robot workspace is characterized and the inverse kinematics equation is obtained. In the paper, design optimization is implemented with genetic algorithms (GA) for optimization considering transmission quality index, manipulability, stiffness and workspace. Here, intended to show the advantages of using the GA, we applied it to a multicriteria optimization problem of 2 DOF micro parallel robot. Genetic algorithms (GA) are so far generally the best and most robust kind of evolutionary algorithms. A GA has a number of advantages. It can quickly scan a vast solution set. Bad proposals do not affect the end solution negatively as they are simply discarded. The obtained results have shown that the use of GA in such kind of optimization problem enhances the quality of the optimization outcome, providing a better and more realistic support for the decision maker.