Manuel Ferre

Remote Laboratories for Education and Research Purposes in Automatic Control Systems

This paper describes the experiences using remote laboratories for education and research in the field of Control Engineering. The use of remote laboratories for education in subjects of control is increasingly becoming a resorted method by the universities in order to offer a flexible service in schedules with greater and better operation of available resources. Nevertheless, for research activities, remote laboratories are not widely used. The aim of this contribution is thereby to apply the experience of remote laboratories in research applications in order to share complex equipments among different researchers. Some experiments are carried out to demonstrate the effectiveness of using remote laboratories in research experiments related to robotic system. The results of the implementation of remote experimentations to control a 3-DOF parallel robot by using Distance Laboratory System (SLD) are exposed. The performance of the system is evaluated by the possibilities and functionality of the proposed remote laboratory platform.

Modular robot systems towards the execution of cooperative tasks in large facilities

Large facilities present with wide range of tasks and modular robots present as a flexible robot solution. Some of the tasks to be performed in large facilities can vary from, achieving locomotion with different modular robot (M-Robot) configurations or the execution of cooperative tasks such as moving objects or manipulating objects with multiple modular robot configurations (M-Robot colony) and existing robot deployments. The coordination mechanisms enable the M-Robots to perform cooperative tasks as efficiently as specialised or standard robots. The approach is based on the combination of two communication types i.e., Inter Robot and Intra Robot communications. Through this communication architecture, tight and loose cooperation strategies are implemented to synchronise modules within an M-Robot configuration and to coordinate M-Robots belonging to the colony. These cooperation strategies are based on a closed-loop discrete time method, a remote clock reading method and a negotiation protocol. The coordination mechanisms and cooperation strategies are implemented into a real modular robotic system, SMART. The need for using such a mechanism in hazardous section of large scientific facilities is presented along with constraints and tasks. Locomotion execution of the mobile M-Robots colony in a bar-pushing task is used as an example for cooperative task execution of the coordination mechanisms and results are presented. We present the results of cooperative task execution using heterogeneous modular robotic system (MRS).It is performed using tight and loosely coupled inter and intra robot configurations.The approach is based on the use of an inventory of three types of basic modules of the modular robot system.The heterogeneity in MRS is an advantageous property for the diverse tasks in large facilities.

Model Based On-Line Energy Prediction System for Semi-autonomous Mobile Robots

Maximizing energy autonomy is a consistent challenge when deploying mobile robots in ionizing radiation or other hazardous environments. Having a reliable robot system is essential for successful execution of missions and to avoid manual recovery of the robots in environments that are harmful to human beings. For deployment of robots missions at short notice, the ability to know beforehand the energy required for performing the task is essential. This paper presents a on-line method for predicting energy requirements based on the pre-determined power models for a mobile robot. A small mobile robot, Khepera III is used for the experimental study and the results are promising with high prediction accuracy. The applications of the energy prediction models in energy optimization and simulations are also discussed along with examples of significant energy savings.

Design of an ergonomic three-finger haptic device for advanced robotic hands control

Nowadays, almost all kinesthetic haptic devices commercially available have been conceived and developed for just one interaction point. Many mechanical conflicts arise when trying to put to work together two or more conventional haptic devices. Due to collisions and other incompatibilities the resulting workspace when using these configurations is usually too small, making this a non-viable option.

Two-hand virtual object manipulation based on networked architecture

A setup for bimanual virtual object manipulation is described in this paper. Index and thumb fingers are inserted in the corresponding thimbles in order to perform virtual object manipulations. A gimble, with 3-rotational degrees of freedom, connects each thimble to the corresponding serial-parallel mechanical structure with 3 actuated DoF. As a result, each finger has 6 DoF, movements and forces can be reflected in any direction without any torque component. Scenarios for virtual manipulation are based on distributed architecture where each finger device has its own real-time controller. A computer receives the status of each finger and runs a simulation with the virtual object manipulation. The information of the Scenario is updated at a rate of 200 Hz. The information from the haptic controller is processed at 1 kHz; it provides a good realism for object manipulation.

Multifinger Haptic Interfaces for Collaborative Enviroments

Haptic interfaces provide users with force information while they are interacting with virtual objects, allowing them to perform manipulation tasks and cooperate. Multi-finger haptic interfaces benefit from the use of several fingers, thereby a large number of degrees of freedom are processed, to improve interaction with virtual environments and increase the sense of immersion. This chapter introduces a new two-finger haptic interface, known as MasterFinger-2. It improves haptic interaction; grasping objects can be easily reproduced by using this device. This interface is based on an open architecture which allows the control of each finger independently via Ethernet. In this sense, it also permits an easy development of cooperative tasks, where users interact directly with their fingers instead of using a tool. MasterFinger-2 is based on a modular design in which each finger has its own mechanical structure and electronic controller. A finger is inserted into a thimble with 6 degrees of freedom, any position and orientation can be consequently achieved by each finger. Forces are reflected in any direction since there are three actuators per finger.

Grasp Mapping Between a 3-Finger Haptic Device and a Robotic Hand

This paper presents the implementation of a robust grasp mapping between a 3-finger haptic device (master) and a robotic hand (slave). Mapping is based on a grasp equivalence defined considering the manipulation capabilities of the master and slave devices. The metrics that translate the human hand gesture to the robotic hand workspace are obtained through an analytical user study. This allows a natural control of the robotic hand. The grasp mapping is accomplished defining 4 control modes that encapsulate all the grasps gestures considered.

Unimanual, bimanual and bilateral weight perception of virtual objects in the Master Finger 2 environment

Human users can obtain information about the physical properties of an object through direct manipulation with one or two hands. Object manipulation of virtual objects using force feedback haptic interfaces is very challenging due to current technological constrains that often affect the information obtained by the user. Here, we describe the Master Finger 2 (MF2), a force feedback device which allows manipulation of one or more objects with one or two hands. We use experimental data to evaluate the performance of MF2 based on its capability to simulate effectively the weight of virtual objects. The results and implications for system design are discussed.

Estimation of normal and tangential manipulation forces by using contact force sensors

This article describes the design and development of a lightweight, adjustable end-effector for different haptic interfaces that estimates normal and tangential forces felt by the user during virtual object manipulation. This thimble was specially designed to provide information about the computed force exerted to the user when manipulating a virtual object with a haptic interface by using four contact force sensors (contact force sensors only measure the force component normal to its active area). Likewise, the aim of this paper is focused on the mechanical design, which relies on developing an adjustable mechanical tool non-finger-size dependant.

A Taxonomy for Heavy-Duty Telemanipulation Tasks using Elemental Actions

In the maintenance of large scientific facilities, telemanipulation procedures can involve various subprocedures which in turn are made up of a sequence of subtasks. This work presents a taxonomy which describes a set of elemental actions for heavy-duty telemanipulation, along with an example of these actions in a standard maintenance subprocedure. As maintenance tasks are often very different at high-level, this generalized way of deconstructing tasks allows a highly adaptable approach to describe the sequence of any procedure, which can then be used for such applications as task monitoring, automation or detection of incomplete tasks. We describe in detail the properties of each elemental action and apply the taxonomy to an example subprocedure to show how the process can be generalizable. An automatic state-machine creation stage is shown, which would be used at the task scheduling stage to simplify calculations carried out during the moment-by-moment execution of the task.