Jeon Il Moon

Neural Network Classification of Brain Hemodynamic Responses from Four Mental Tasks

We investigate subjects’ brain hemodynamic activities during mental tasks using a nearinfrared spectroscopy. A wavelet and neural network-based methodology is presented for recognition of brain hemodynamic responses. The recognition is performed by a single layer neural network classifier according to a backpropagation algorithm with two error minimizing techniques. The performance of the classifier varied depending on the neural network model, but the performance was usually at least 90%. The classifier usually converged faster and attained a somewhat greater level of performance when an input was presented with only relevant features. The overall classification rate was higher than 94%. The study demonstrates the accurate classifiablity of human brain hemodynamic useful in various brain studies.

The beginning of neurohaptics: Controlling cognitive interaction via brain haptic interface

This study showed an example of neurohaptic interface which can be the direct connector between haptics and brain. We investigated the neural activities of motion which are essential tasks for haptic interaction. Eating was adopted to explore the neural activities from the functional near-infrared spectroscopy (fNIRS) imaging. Subjects carried out real motion, action observation, and motor imagery. From this study we convinced that the action observation and motor imagery may create the similar neural activities to the active movement. In addition, we showed the feasibility of an fNIRS integrated brain haptic interaction based on the neural mechanism of action observation. Implications of this study suggested that the neurohaptics can play a more active role in realistic haptic interaction for the real applications including brain computer interface.

Cortical activation pattern for grasping during observation, imagery, execution, FES, and observation-FES integrated BCI: An fNIRS pilot study

Passive movement, action observation and motor imagery as well as motor execution have been suggested to facilitate the motor function of human brain. The purpose of this study is to investigate the cortical activation patterns of these four modes using a functional near-infrared spectroscopy (fNIRS) system. Seven healthy volunteers underwent optical brain imaging by fNIRS. Passive movements were provided by a functional electrical stimulation (FES). Results demonstrated that while all movement modes commonly activated premotor cortex, there were considerable differences between modes. The pattern of neural activation in motor execution was best resembled by passive movement, followed by motor imagery, and lastly by action observation. This result indicates that action observation may be the least preferred way to activate the sensorimotor cortices. Thus, in order to show the feasibility of motor facilitation by a brain computer interface (BCI) for an extreme case, we paradoxically adopted the observation as a control input of the BCI. An observation-FES integrated BCI activated sensorimotor system stronger than observation but slightly weaker than FES. This limitation should be overcome to utilize the observation-FES integrated BCI as an active motor training method.

Study on automatic speed adaptation treadmills

This paper examines and summarizes the research trends in the field of rehabilitation robotics for treadmills that automatically adapt to the walkers desired speed. Treadmill training is a method of ambulatory rehabilitation for patients who have lost their ambulatory function before or after a joint replacement surgery, or from arthritis, a stroke, or a spinal cord injury. The existing treadmill training method alone has been claimed to have a positive effect on the patients condition; during training, however, a problem incurs in which conscious brain functions needed for ambulation when walking or running at a fixed speed are hindered. To solve this problem, we briefly introduce and compare a self-paced treadmill and its methods of use.

Kinematic Design Consideration Based on Actuator Placement of Five-Bar Planar Robot for Arm Rehabilitation

In the design of upper limb rehabilitation robots, critical issues to be considered are large workspace with minimum singularities to cover enough patients’ upper limb range of motion and higher manipulability for the patients to easily and freely move their arm with applying almost the same force to every direction in a given posture. This paper presents an analysis of the suggested kinematic design considerations of five-bar planar mechanism according to the actuator locations. A comparison between two different five-bar linkage types is given. Finally, several open challenges for the applicability of five-bar planar mechanisms are discussed from the kinematic point of view to upper limb rehabilitation robots.

Study of Mechanism for Wear Adjustment with Electro Wedge Brake

Electro wedge brake (EWB) have been suggested and improved for enhancing the braking efficiency and reducing the weight and power of actuating motor than electro mechanical brake (EMB). This is due to self-reinforcement features of the wedge mechanism. On the other hand, the conventional hydraulic brake system has the passive wear adjustment without any sensors and actuators. This is because of the sealing rubber which is disposed between the hydraulic cylinder and piston, and supply the piston’s same restoring strokes regardless of pad’s wear amounts. This feature leads to the uniform distance between the disc and the pad. In comparison, electronic brake systems such as EMB and EWB don’t have the hydraulic piston and cylinder with the sealing rubber. Therefore the electronic brake systems cannot use the function of this passive wear adjustment. However, if the electronic brake system has gap sensors for detecting distances between the pad and the disc, and actuators for keeping the uniform distances between the pad and the disc, then the brake system can have the function of wear adjustments. One of our research goals is the embodiment of cost-effective and feasible wear adjustment mechanism which is proper to EWB. In this paper, as a chain of EWB’s development, we describe the proposed mechanism for wear adjustment with EWB. Further we describe the feasibility of this mechanism with the simulation study.

Cooperative Control of a Single-user Multi-robot Teleoperated system for maintenance in offshore plants

In this paper, we propose a cooperative control method of a single-user multi-robot (SUMR) teleoperated system for maintenance in offshore plants that is designed to perform in a 1:N mode (here, “1” refers to the number of user, and “N” denotes the number of slave robots), in which a single user teleoperates a number of slave robots directly to conduct a specific operation or in an autonomous cooperation mode between slave robots in order to overcome the limitation of the 1:1 teleoperation mode. This paper is also designed to extend compatibility in the SUMR teleoperated system’s controller. A haptic device, which is one of the master device, is used for duplex transmission of control and status data between a robotic manipulator and user. In this paper, a new haptic library is also designed to connect between a haptic device (PHANToM premium, Sensable) and a controller based on LabVIEW. The designed new haptic library (DLL, dynamic linking library) that is created using C++ is called in LabVIEW, which is a GUI (graphical user interface) based software development tool.

Introduction of Human-Robot Cooperation Technology at Construction Sites

Currently, a new construction method using a robotic system is widely spreading in construction sites. This study is related to introduction of humanrobot cooperation technology which can improve convenience and productivity through the efficient interaction between a worker and a robotic system while doing glass panel installation works. Based on the analysis on glass panel installation with a glazing robot, functional requirements and approaches to address these requirements that can implement human-robot cooperative manipulation at construction sites. A practical example, which is applied to a specific target construction site, is also described in this paper. After field test at a real construction site, productivity and safety of the proposed system are compared with the existing glass panel installation system.

Trends in national standardization of usage environment safety and performance evaluation of gait training equipment

Gait training equipment, which enables the handicapped and elderly to perform activities independently, primarily includes a rehabilitation exercise robot that assists a persons movement by detecting limb motions and a robot that moves the arms and hands by using a persons neuronal signals. Gait training equipment is part of the category of medical robots, and specific standardized documents are required after ensuring individual standardization of rehabilitation robots. We propose the necessity of the standardized test method for usage environment safety and performance evaluation of gait training equipment.

Management of a Single-User Multi-Robot Teleoperated System for Handling Large Valves in Offshore Plants

This paper proposes a new approach to task management method of a single‐user multi‐robot teleoperated system for handling large valves in offshore plants. The task management method is designed to perform a 1:N mode (here, “1” refers to the number of operators, and “N” denotes the number of robots), in which a single operator teleoperates a number of slave robots directly to conduct a large valve handling task, or in an autonomous cooperation mode between slave robots in order to overcome the limitations of the aforementioned 1:1 (here, “1” refers to the number of operators and slave robots) teleoperation mode. The aforementioned management method is responsible for the role sharing and integration of slave robots to divide the operation mode of the slave robots into various types according to the operator’s intervention level and the characteristics of the target operation (valve handling) beforehand and to perform the target operation using the robot operation mode selected by the operator.