The application of implant technology for cybernetic systems

Objective: To assess the usefulness, compatibility, and long-term operability of a microelectrode array into the median nerve of the left arm of a healthy volunteer, including perception of feedback stimulation and operation of an instrumented prosthetic hand. Setting: The study was carried out from March 14 through June 18, 2002, in England and the United States. Results: The blindfolded subject received feedback information, obtained from force and slip sensors on the prosthetic hand, and subsequently used the implanted device to control the hand by applying an appropriate force to g rip an unseen object. Operability was also demonstrated remotely via the Internet, with the subject in New York, NY, and the prosthetic hand in Reading, England. Finally, the subject was able to control an electric wheelchair, via decoded signals from the implant device, to select the direction of travel by opening and closing his hand. The implantation did not result in infection or any perceivable loss of hand sensation or motion control. The implant was finally extracted because of mechanical fatigue of the percutaneous connection. Further testing after extraction has not indicated any measurable long-term defects in the subject. Conclusions: This implant may allow recipients to have abilities they would otherwise not possess. The response to stimulation improved considerably during the trial, suggesting that the subject learned to process the incoming information more effectively.

A haptically enabled low-cost reconnaissance platform for law enforcement

Traditionally, the control system of a modern teleoperated mobile robot consists of one or more two-dimensional joysticks placed on a control interface. While this simplistic interface allows an operator to remotely drive the platform, feedback is limited to visual information supplied by on-board cameras. Significant advances in the field of haptics have the potential to meaningfully enhance situational awareness of a remote robot. The focus of this research is the augmentation of Deakin University's OzBot trade MkIV mobile platform to include haptic control methodologies. Utilising the platform's inertial measurement unit, a remote operator has the ability to gain knowledge of the vehicle's operating performance and terrain while supplying a finer level of control to the drive motors. Our development of a generic multi-platform ActiveX allows the easy implementation of haptic force feedback to many computer based robot controllers. Furthermore, development of communication protocols has progressed with Joint Architecture for Unmanned Systems (JAUS) compliance in mind. The haptic force control algorithms are presented along with results highlighting the benefits of haptic operator feedback on the MklV OzBot trade chassis.

Extending an industrial root controller : implementation and applications of a fast open sensor interface

An overview is given of the design and implementation of a platform for fast external sensor integration in an industrial robot system called ABB S4CPlus. As an application and motivating example, the implementation of force-controlled grinding and deburring within the AUTOFETT-project is discussed. Experiences from industrial usage of the fully developed prototype confirms the appropriateness of the design choices, thus also confirming the fact that control and software need to be tightly integrated. The new sensor can be used for the prototyping and development of a wide variety of new applications

Sistema de navegação para robôs móveis autônomos

The main task and one of the major mobile robotics problems is its navigation process. Conceptualy, this process means drive the robot from an initial position and orientation to a goal position and orientation, along an admissible path respecting the temporal and velocity constraints. This task must be accomplished by some subtasks like robot localization in the workspace, admissible path planning, trajectory generation and motion control. Moreover, autonomous wheeled mobile robots have kinematics constraints, also called nonholonomic constraints, that impose the robot can not move everywhere freely in its workspace, reducing the number of feasible paths between two distinct positions. This work mainly approaches the path planning and trajectory generation problems applied to wheeled mobile robots acting on a robot soccer environment. The major dificulty in this process is to find a smooth function that respects the imposed robot kinematic constraints. This work proposes a path generation strategy based on parametric polynomials of third degree for the 'x' and 'y' axis. The 'theta' orientation is derived from the 'y' and 'x' relations in such a way that the generated path respects the kinematic constraint. To execute the trajectory, this work also shows a simple control strategy acting on the robot linear and angular velocities

Desenvolvimento de um Sistema de Visão Global para uma Frota de Mini-Robôs Móveis

Navigation based on visual feedback for robots, working in a closed environment, can be obtained settling a camera in each robot (local vision system). However, this solution requests a camera and capacity of local processing for each robot. When possible, a global vision system is a cheapest solution for this problem. In this case, one or a little amount of cameras, covering all the workspace, can be shared by the entire team of robots, saving the cost of a great amount of cameras and the associated processing hardware needed in a local vision system. This work presents the implementation and experimental results of a global vision system for mobile mini-robots, using robot soccer as test platform. The proposed vision system consists of a camera, a frame grabber and a computer (PC) for image processing. The PC is responsible for the team motion control, based on the visual feedback, sending commands to the robots through a radio link. In order for the system to be able to unequivocally recognize each robot, each one has a label on its top, consisting of two colored circles. Image processing algorithms were developed for the eficient computation, in real time, of all objects position (robot and ball) and orientation (robot). A great problem found was to label the color, in real time, of each colored point of the image, in time-varying illumination conditions. To overcome this problem, an automatic camera calibration, based on clustering K-means algorithm, was implemented. This method guarantees that similar pixels will be clustered around a unique color class. The obtained experimental results shown that the position and orientation of each robot can be obtained with a precision of few millimeters. The updating of the position and orientation was attained in real time, analyzing 30 frames per second

Variable structure controller and observer applied to induction machine

This work will propose the control of an induction machine in field coordinates with imposed stator current based on theory of variable structure control and sliding mode. We describe the model of an induction machine in field coordinates with imposed stator current and we show the design of variable structure control and sliding mode to get a desirable dynamic performance of that plant. To estimate the inaccessible states we will use a state observer (estimator) based on field coordinates induction machine. We will present the results of simulations in any operation condition (start, speed reversal and load) and with parameters variation of the machine compared to a PI control scheme.

Lumped Element Modeling of a Flexible Manipulator System

This paper is concerned with a modeling method that can be used for an experimental identification of a dynamic system. More specifically, an equivalent lumped element system is presented to represent in a unique and exact manner a complete proportional-derivative (PD) controlled servo positioning system having a flexible manipulator. The impedance and mobility approach is used to transform the P and D control gains to an electrical spring and an electrical damper, respectively. The impedance model method is used to transform the flexible manipulator to a coupled system between a single contact mass at the driving position and a series of noncontact masses each of which is connected to the contact mass via a resilient member. This method is applicable whenever the driving point response of such a manipulator is available. Experimental work is presented to support the theory developed.

Survey of architectures and optimizations for wide bandwidth envelope amplifier

In the last years, RF power amplifiers are taking advantage of the switched dc-dc converters to use them in several architectures that may improve the efficiency of the amplifier, keeping a good linearity. The use of linearization techniques such as Envelope Elimination and Restoration(EER) and Envelope Tracking (ET) requires a very fast dc-dc power converter to provide variable voltage supply to the power amplifier but theoretically the efficiency can be much higher than using the classical amplifiers belonging to classes A, B or AB. The purpose of this paper is to analyze the state of the art of the power converters used as envelope amplifiers in this application. The power topologies will be explored and several important parameters such as efficiency, bandwidth will be discussed.

Minimum jerk trajectory control for rehabilitation and haptic applications

Smooth trajectories are essential for safe interaction in between human and a haptic interface. Different methods and strategies have been introduced to create such smooth trajectories. This paper studies the creation of human-like movements in haptic interfaces, based on the study of human arm motion. These motions are intended to retrain the upper limb movements of patients that lose manipulation functions following stroke. We present a model that uses higher degree polynomials to define a trajectory and control the robot arm to achieve minimum jerk movements. It also studies different methods that can be driven from polynomials to create more realistic human-like movements for therapeutic purposes.

Method and apparatus for haptic control

The present invention provides remote interfacing utilising haptic technology. In a first aspect there is provided a haptic grasping interface comprising a plurality of finger interaction points, with actuators connected at one end to an actuator control mechanism. The mechanism is mounted remotely from the grasping interface, inverse to the finger interaction points, for manipulation of these points. The grasping points comprise pulleys which route the actuators through a cable tension and transmission system. A second aspect provides haptic augmentation to an operator, which indicates to the operator the state of a control input to a controlled device. A third aspect provides a means of simulating motion where haptic feedback is provided to a user in correspondence with the movement of the user within a pod environment.

Method and apparatus for haptic control

The present invention provides remote interfacing utilising haptic technology. In a first aspect there is provided a haptic grasping interface comprising a plurality of finger interaction points, with actuators connected at one end to an actuator control mechanism. The mechanism is mounted remotely from the grasping interface, inverse to the finger interaction points, for manipulation of these points. The grasping points comprise pulleys which route the actuators through a cable tension and transmission system. A second aspect provides haptic augmentation to an operator, which indicates to the operator the state of a control input to a controlled device. A third aspect provides a means of simulating motion where haptic feedback is provided to a user in correspondence with the movement of the user within a pod environment.

Method and apparatus for haptic control

The present invention provides remote interfacing utilising haptic technology. In a first aspect there is provided a haptic grasping interface comprising a plurality of finger interaction points, with actuators connected at one end to an actuator control mechanism. The mechanism is mounted remotely from the grasping interface, inverse to the finger interaction points, for manipulation of these points. The grasping points comprise pulleys which route the actuators through a cable tension and transmission system. A second aspect provides haptic augmentation to an operator, which indicates to the operator the state of a control input to a controlled device. A third aspect provides a means of simulating motion where haptic feedback is provided to a user in correspondence with the movement of the user within a pod environment.

Method and apparatus for haptic control

The present invention provides remote interfacing utilising haptic technology. In a first aspect there is provided a haptic grasping interface comprising a plurality of finger interaction points, with actuators connected at one end to an actuator control mechanism. The mechanism is mounted remotely from the grasping interface, inverse to the finger interaction points, for manipulation of these points. The grasping points comprise pulleys which route the actuators through a cable tension and transmission system. A second aspect provides haptic augmentation to an operator, which indicates to the operator the state of a control input to a controlled device. A third aspect provides a means of simulating motion where haptic feedback is provided to a user in correspondence with the movement of the user within a pod environment.

Method and apparatus for haptic control

The present invention provides remote interfacing utilising haptic technology. In a first aspect there is provided a haptic grasping interface comprising a plurality of finger interaction points, with actuators connected at one end to an actuator control mechanism. The mechanism is mounted remotely from the grasping interface, inverse to the finger interaction points, for manipulation of these points. The grasping points comprise pulleys which route the actuators through a cable tension and transmission system. A second aspect provides haptic augmentation to an operator, which indicates to the operator the state of a control input to a controlled device. A third aspect provides a means of simulating motion where haptic feedback is provided to a user in correspondence with the movement of the user within a pod environment.