César Peña

Efficient human hand kinematics for manipulation tasks

This work is focused on obtaining efficient human hand models that are suitable for manipulation tasks. A 24 DoF kinematic model of the human hand is defined to realistic movements. This model is based on the human skeleton. Dynamic and static constraints have been included in order to improve the movement realism. Two simplified hand models with 9 and 6 DoF have been developed according to the constraints predefined. These simplified models involve some errors in reconstructing the hand posture. These errors are calculated with respect to the 24 DoF model and evaluated according to the hand gestures. Finally, some criteria are defined to select the hand description best suited to the features of the manipulation task.

Bilateral control by state convergence based on transparency for systems with time delay

This paper proposes a new methodology for designing master and slave controllers based on state convergence that aims to reach the most transparency considering communication time delay. This method shows a modified scheme of the state convergence algorithm that feeds back the state of the slave to the master controller. All this information (position, velocity and torque) is processed in order to implement the desired master behavior that has to guarantee the stability of the system and the best remote impedance reflection as possible. This paper shows some experiments that prove the performance of this methodology for a second order-modeled system with 3 degrees of freedom. Moreover, this methodology can also be applied in higher order systems of teleoperation models.

Teleoperation of a Robot Using a Haptic Device with Different Kinematics

This paper presents a bilateral control method by state convergence for teleoperation systems where the master and slave robots do not necessarily have homothetic kinematics. This method uses a virtual robot to relate the kinematics of the master and slave robots. An application of this type of control is also presented in which a robot of three degrees of freedom is teleoperated by using a commercial haptic device with six degrees of freedom.

Underwater Parallel Robot for oceanic measuring and observations-REMO I: development and navigation control advances

The REMO I is a remotely teleoperated underwater vehicle developed for measuring and observing maritime environments as its mandatory task. This robot has been built based on a parallel structure (Stewart-Gough platform), with the capability of changing its geometry in order to facilitate the navigation within complex maneuvers. In addition, both orientation and propulsion systems can change in order to provide even more underwater dexterity. A thruster located in the back of its structure, which drives the vehicle forward, composes the main propulsion system of the robot. This extended abstract briefly introduces some fundamental issues related to the mechanical design, instrumentation and the control capabilities of this system.

Bilateral controller design based on transparency in the state convergence framework

This paper describes a new methodology for designing bilateral controllers based on transparency that applies a modified scheme of control by state of convergence. The design is based on modelling the behavior of the master and slave which regard state space equations, and also taking into account that perfect transparency cannot be reached. This methodology allows designing the controllers in order to obtain the convergence between the state of the master and the slave. Furthermore, it consequently provides a higher degree of transparency to the operator. The paper explains criteria in achieving convergence between the master and the slave, and so as with transparency on a steady state. A set of equations that calculate controller gains have been obtained by applying such criteria. In order to verify this new methodology, a master-slave system of 3 DoF have been used.

Advances in developing telemanipulators for an underwater robot - Remo II

This paper presents a brief description of a novel underwater robot prototype, based on a parallel-serial structure. The underwater robot is composed of two subsystems: navigation and manipulation systems. This paper is focused on the first system: manipulation, aiming to introduce some advances related to it. Several systems characteristics rely on the capability of reflecting the environment interaction forces to the human operator and addressing virtual constraints that allow the haptic device to emulate the real robot. Finally, the results obtained show the capabilities and the reliability of the tele-operation system, which will allow the robot to perform complex underwater tasks missions.

TELEOPERATION OF A MANIPULATOR WITH A MASTER ROBOT OF DIFFERENT KINEMATICS: USING BILATERAL CONTROL BY STATE CONVERGENCE

This paper presents the teleoperation method of manipulators which have different kinematics with respect of the master robots using bilateral control by state convergence. This method makes a relation between the kinematics of the master and slave robot using a virtual robot. This method allows controlling manipulators which are a part of different kinds of robot as: climber robots, underwater robots, human robots, etc.