BACKGROUND:Ultrasonic neuromodulation (UNMOD) provides a non-invasive brain stimulation. However, the high-resolution region-specificity of UNMOD with a single element transducer combined with a mechanical positioning system could have limits due to the intrinsic positioning error from mechanical systems. OBJECTIVE/HYPOTHESIS:A phased array system could lead to highly selective neuromodulation with electronic control. METHODS:A specialized phased-array system with a robotic arm is implemented for a rhesus monkey model. Various primary motor cortex areas related to tail, hand, and mouth were stimulated with a 200 μm step size. The ultrasonic parameters were ISPTA of 840 mW/cm2, pulse repetition frequency of 100 Hz, and a 5% duty factor at 600 kHz. The induced movement were recorded and analyzed. RESULTS:Separate digits, mouth, and tongue motions were successfully induced by electronically controlling the focus. The identical body part movement could be induced when the focus was moved back to the identical primary motor cortex with electronic control. Accordingly, the reproducibility of UNMOD could be partially validated with rhesus monkey model. CONCLUSION:A phased-array system appears to have a potential for the non-invasive and region-selective neuromodulation method.

There has been an increasing demand for robotic coil positioning during repetitive transcranial magnetic stimulation (rTMS) treatment. Accurate coil positioning is crucial because rTMS generally targets specific brain regions for both research and clinical application with other reasons such as safety, consistency and reliability and individual variablity. Some previous studies have employed industrial robots or co-robots and showed they can more precisely stimulate the target cortical regions than traditional manual methods. In this study, we not only developed a custom-TMS robot for better TMS coil placement but also analyzed the therapeutic effects on depression. Treatment effects were evaluated by measuring regional cerebral blood flow (rCBF) using single-photon emission computed tomography and depression severity before and after rTMS for the two positioning methods. The rTMS preparation time with our robotic coil placement was reduced by 53% compared with that of the manual method. The position and orientation errors were also significantly reduced from 11.17 mm and 4.06° to 0.94 mm and 0.11°, respectively, confirming the superiority of robotic positioning. The results from clinical and neuroimaging assessments indicated comparable improvements in depression severity and rCBF in the left dorsolateral prefrontal cortex between the robotic and manual rTMS groups. A questionnaire was used to determine the patients’ feelings about the robotic system, including the safety and preparation time. A high safety score indicated good acceptability of robotic rTMS at the clinical site.

: This paper proposes an inspection robot that can operate on a single square rail. Various inspection robots have been developed to identify emergency situations in industrial environments, such as those involving fires or individuals with cardiac arrest. Because the robots must operate in wide areas and long tunnels, they are designed to move along a rail installed on the ceiling. Double rail track are typically used to ensure the stability of robot movement. However, the cost for installing a double rail track is nearly two times that for a single rail track. Moreover, it is challenging to install double rail tracks while ensuring the same curvature and interval between the two rails. Therefore, in this study, an inspection robot that operate on a single square rail track is developed. To ensure stable movement in the longitudinal and lateral directions, two passive guide parts are used, and the main active wheel is allowed to move on the upper side of the square rail. The prototype was manufactured, and experiments were performed for different robot velocities.

Brain stimulation using noninvasive methods has been widely adopted in neuropsychiatric disorder therapies. Clinicians who use the innovative methods situate the stimulator manually in a typical setup. However, this causes practical difficulties in precisely locating the stimulation device at a desired pose. This article proposes a robotic positioning system that can precisely position a brain stimulation device at the desired pose. The design concepts are focused on the development of a system with a workspace specialized in noninvasive brain stimulation. To stimulate the overall area around the upper part of the head, the system is designed to have a specific posture with a six-degrees-of-freedom (6-DOF) movable parallel mechanism and a 1-DOF extra revolute joint. The combined system not only significantly increases the workspace of the system but also increases its physical safety. In the movable parallel mechanism, we realize sufficient mobility for the robotic device using three- ${\bar{\bf{P}}}$ R PS chains ( ${\bar{\bf{P}}}$ : curved prismatic joint, R: revolute joint, P: prismatic joint, and S: spherical joint). The curved prismatic joint ( ${\bar{\bf{P}}}$ ) is a revolute joint realized by curved rail and enables efficient movement of the stimulator around the subject's head. Furthermore, the parallel mechanism offers good physical safety and load-carrying capacity. The moving platform, which is close to the head, exhibits low inertia, and there is no rapid change in the acceleration due to the failure of control because the moving platform is moved as a combination of joint movements. The system can accommodate stimulators of varying weights, such as those employing transcranial magnetic stimulation and ultrasound transducers. A prototype of the proposed system was developed using the design specifications, and its performance was verified experimentally.

Roll stability is an important issue that must be addressed to ensure the safety of passengers. In this research, the relationship between the roll angle of a vehicle and the locations of springs and dampers in cornering is investigated. Motion recovery is also studied according to the locations of the springs and dampers. Using these relations, the optimal locations of springs and dampers for improving roll stability are suggested. The model used for analysis of the roll angle is a planar double wishbone suspension. In addition, proportional damping in which the coefficient of the damper is proportional to the coefficient of the spring is used to analyze the damper. Furthermore, a transfer function is derived to analyze motion recovery. Optimization is performed using the function of the roll angle as an objective function, and using the constraint of the damping ratio. In optimization, the major variables are the locations and directions of the springs and dampers. The boundary conditions are determined by considering the area in which the springs and dampers can be installed. The outcome of this study shows that the roll angle can be decreased by 9.1% to 19.5% depending on the suspensions. Furthermore, the damping ratio of the system is increased.

This paper proposes a geometric approach to the conditions for mode decoupling of a vibration system of an elastically supported single rigid body and presents the conditions that the system has only pure rotation modes of vibration. A small oscillation of a rigid body is indeed a repetitive screw motion and thus vibration modes are expressed by screws in general, which results in the difficulty involved in solving a vibration problem. The complexity of a vibration system can be alleviated for both analysis and synthesis if the system has only rotation modes. In order to acquire the decoupling techniques, this paper begins by investigating a stiffness matrix which can be separated into the sum of two rank 3 stiffness matrices, which are realizable by using co-reciprocal line vectors. From the co-reciprocity, the separable stiffness matrix can be regarded as a linear transformation between two 3-systems of screws containing only line vectors. Using the properties of the linear transformation and the screw systems, the conditions for mode decoupling, or the conditions for only pure rotation modes are derived and described by geometric relations between inertia and stiffness, and three cases of vibration systems with simple geometric nature are identified.

An anthropomorphic prosthetic hand for wrist or forearm amputees is developed herein. The prosthetic hand was designed with an underactuated mechanism, which makes self-adaptive grasping possible, as well as natural motions such as flexion and extension. The finger and thumb modules were designed with four degrees of freedom by motions of the distal interphalangeal, proximal interphalangeal, and metacarpophalangeal joints. In this research, we pursued several novel trials in prosthetic hand design. By using two four-bar linkages composed of a combination of linkages and gears for coupling joints at each finger, it was possible to make a compact design, and the linkage has advantages such as accurate positioning, uniform power transmission, and high payload. Also, by using constant-velocity joints, torque is transferred to finger modules regardless of adduction/abduction motions. In addition, adduction/abduction and self-adaptive grasping motions are passively realized using torsional springs. The developed prosthetic hand was fabricated with a weight of 475 g and a human hand size of 175 mm. Experiments with diverse objects showed its good functionality.

Finger amputations are the most common upper limb amputation, and they occur approximately 100 times more often than hand amputations. We developed a prosthetic hand for amputees with a thumb and metacarpal. In this case of amputation, the installation of actuators and electrical components is difficult because space is considerably limited owing to the residual metacarpal. This design issue is solved by installing actuators vertically between finger modules and the mounting part where the electrical parts are embedded. With this design, the arrangement between the palm of the patient and the fingers of the prosthetic hand can be adjusted as well. Weight is also an especially important design issue in the development of a practical prosthetic hand because the patient perceives that weight. Most prosthetic hands are attached to the residual limb of the amputee by compressing the contact surface between the product and the amputated body part of the patient. Heavy weight causes users to feel discomfort and fatigue over extended periods of usage. In this study, all frames used in the proposed prosthetic hand were fabricated from nylon using multi-jet-fusion three-dimensional printing. As a result, the weight of the developed prosthetic hand was only 152.32 g but still had the desired strength and stiffness. Each prosthetic finger has four-degree-of-freedom. The distal interphalangeal, proximal interphalangeal, and metacarpophalangeal joints are coupled and driven by power from an actuator, which is transferred to each joint through the tendons. Adduction, abduction, and self-adaptive grasping motions were passively realized using linear and torsional springs. The prototype was fabricated based on these design concepts and functions, and its functionality was verified in experiments using diverse objects.

When the design of a vibration system requires a broad bandwidth, the numbers and the ratios of energy peaks become major design factors. In particular, within a specific range of frequency, an increase in the number of peaks can widen the valid working bandwidth by decreasing the distances between peaks. In this paper, a planar symmetric dual-body vibration system is used to implement desired work ratios at six target frequencies. The geometrical relation between vibration modes and energy peaks is investigated to develop the design method and introduces geometrical representation of vibration modes of a symmetric dual-body system together. Six vibration modes of a symmetric dual-body system are divided into two groups with three vibration modes that represent the centers of vibration. It is shown that the orthocenters of two modal triangles of each of two rigid bodies coincide with its center of mass. The frequency responses to both direct and base excitations are derived in terms of vibration centers and target frequencies, and thus work ratios are obtained. Finally, the derived equation of work ratios is used to determine the modal matrix composed of the vibration modes when the desired mass, specific work ratios, and target resonant frequencies are given. Consequently, the corresponding stiffness matrix is found and realized. Numerical examples of four cases with different work ratios are presented to illustrate the proposed design method.

Although non-invasive brain stimulation techniques do not involve surgical procedures, the challenge remains in correctly locating the stimulator from outside the head. There is a limit to which one can manually and precisely position and orient the stimulator or repeatedly move the stimulator around the same position. Therefore, in this study, we developed a serial robot with 6 degrees-of-freedom to move the stimulator and a neuro-navigation system to determine the stimulus point from looking at the shape of the subject's brain. The proposed robot applied a spherical mechanism while considering the safety of the subject, and the workspace of the robot was designed considering the shape of the human head. Position-based visual servoing was applied to compensate for unexpected movements during subject stimulation. We also developed a neuro-navigation system that allows us visually to check the focus of the stimulator and the human brain at the same time and command the robot to the desired point. To verify the system performance, we first performed repeatability and motion compensation experiments of the robot and then evaluated the repeated biosignal response experiments through transcranial magnetic stimulation, a representative technique of non-invasive brain stimulation.

A new prosthetic finger including an actuator in the proximal phalanx has been developed for finger amputees. By designing the prosthetic finger with the actuator inside, the mounting part does not need to include the actuators; this leads to a simple and compact design of the prosthetic finger. Thus, the comfort of wearing and the aesthetics for the user are improved. The proposed prosthetic finger is designed as under-actuated mechanism having four degree-of-freedoms (4-DOFs) with the distal interphalangeal joint (DIP joint) driven directly (1-DOF) and the proximal interphalangeal joint (PIP joint) and the metacarpophalangeal joint (MCP joint) driven indirectly (3-DOFs). The indirect driving is realized using leaf springs. The force from the actuator is transferred to each phalanx by the tendon. The finger enables self-adaptive grasping according to object shapes as well as flexion/extension motions and adduction/ abduction motions. The prototype was manufactured using 3D printing and machining. Experiments show the feasibility of the proposed prosthetic finger.

This article presents a new design method of a planar 3-degree-of-freedom serial manipulator-type electromagnetic vibration energy harvester in which any desired ratio of power peaks and three target resonant frequencies can be specified arbitrarily. The design of the harvester aims to achieve minimum difference between the power peaks generated at target frequencies. The geometrical positions of three normal modes are first determined and the corresponding stiffness matrix of the harvester is found. Second, the stiffness matrix can be synthesized by three serially connected torsional springs. Third, the leaf hinge joints corresponding to torsional springs are designed using the newly developed design equations. Finally, the array and the locations of the magnets are found using the sequential quadratic programming (SQP) algorithm. The experiments are conducted to verify the design method. Three resonant frequencies are measured at 23.4, 29.2, and 34.8 Hz comparing to the target frequencies of 25, 30, and 35 Hz. The peak powers of 1.28, 0.89, and 1.32 mW are obtained across the optimal load resistor of 1.01 kΩ under the condition of the constant acceleration of 1.5 m/s2.

SNOMED CT 표준 의학 용어 체계를 활용하여 진료기록을 작성하기 위해서는 용어 체계에 포함된 방대한 양의 용어들 중 적합한 용어를 빠른 시간에 선택하는 것이 필요하다. 기존의 검색 브라우저들은 검색 결과를 단순 목록으로 나열하므로 유사한 용어들을 사용자가 구분하여 선택하기 어려운 문제가 있다. 본 논문에서는 용어체계의 특성을 고려하여 효과적인 용어의 검색이 가능한 브라우저를 제안한다. 제안하는 시스템에서는 간략화된 트리 형태로 검색 결과의 계층적 구조를 함께 표시하므로 검색 결과 용어들 중 원하는 용어를 빠르게 선택할 수 있다. 그리고 시스템 설계와 구현을 통해 제안하는 방법의 효과성을 입증한다. To write a medical record using SNOMED CT standard clinical terminologies, it is necessary to find and select an appropriate terminology from the huge volume of terminologies within short time. Using previous SNOMED CT search browsers, it is very difficult to select appropriate one from search results since they provide a simple list-up of similar candidate terminologies. This paper proposes a novel search browser which supports effect searching of clinical terminology by utilizing characteristics of SNOMED CT. The proposed system provides a simplified tree-view representing hierarchical structures of search results which enables fast selection of appropriate terminology from the search results. Design and Implementation of the system proves effectiveness of the proposed approach.

RFID는 유헬스의 핵심 기술로서 환자 위치 추적 관리, 의료 자산관리 등 다양한 목적으로 의료기관에 적용될 수 있다. 하지만, 정작 의료기관에서는 높은 도입 비용으로 인하여 RFID 도입이 기대와 달리 적극적이지 못한 실정이다. 도입 검토 단계에서 정확한 비용과 도입 효과를 산정하는 것은 의료기간에서의 RFID 확산에 꼭 필요하다. 본 논문에서는 의료기관에서 RFID 도입시 예상되는 비용 및 효율을 평가하기 위한 시뮬레이션 기법을 제안한다. 의료기관을 대상으로 하여 태그를 부착한 환자의 이동을 가상으로 모델링하는 기법을 제시한다. 그리고 환자의 이동에 따른 RFID 태그 인식 시뮬레이션을 통해 태그 인식 이벤트를 생성하는 방법을 제시한다. As a key technology of U-health, RFID can be applied to the hospitals in a variety of cases such as patient tracking, medical instrument management, and so on. However, adoption of RFID in healthcare does not reach expectations because of huge cost. Exact estimation of cost and effectiveness will boost adoption of RFID in healthcare. This study proposes a novel simulation technique to evaluate cost and effectiveness of RFID in hospital environment. To do this, this study proposes a technique for modeling patients' movements in a hospital. Based on the model, this study provides how to obtain tag event dataset by means of simulating identifications of RFID tags that are attached to patients.

물류, 의약품, 병원 등 다양한 환경에서 RFID의 도입이 확산되고 있다. RFID의 도입을 위해서는 EPC정보서비스(EPCIS)등과 같은 핵심 RFID S/W의 성능 및 적합성 평가가 선행되어야 하며, 이때 다양한 종류의 비즈니스 이벤트 데이터셋이 필수적으로 요구된다. 본 논문에서는 RFID 응용환경을 시뮬레이션하는 접근방법을 통해 보다 실제와 유사한 RFID 비즈니스 이벤트 데이터셋을 생성하기 위한 기법을 제안한다. 제안하는 모델은 페트리넷을 기반으로 하여 다양한 RFID 환경에 대한 유연한 표현이 가능한 특징이 있다. 또한, 실제 RFID 환경의 시뮬레이션이 가능함에 따라 RFID 도입여부 검토에서도 유용하게 활용될 수 있다. Adoption of RFID has become widespread including logistics, drug supply-chain, and healthcare. To adopt RFID, we need to evaluate performance and feasibility of RFID S/W such as EPC Information Service (EPCIS), which demands a variety of test datasets of RFID business events. This paper proposes a novel method for creating RFID business events dataset by means of the simulation of RFID infrastructure. Proposed model provides a flexible representation capability since this is based on well-known petri-net. In addition, it can also be useful when determining adoption of RFID as it supports simulation of RFID environment.

This paper presents an RSN Tool to generate input datasets for testing RFID middleware. As RFID middleware takes an important role in entire RFID systems, its performance should be carefully evaluated under various business conditions. In general, evaluation of the RFID middleware requires a huge cost because the numerous RFID readers and tags need to be deployed to acquire the tag event stream. To facilitate low-cost testing of the middleware, we propose the RSN Tool which provides means of designing a virtual RFID infrastructure and generates a tag event stream automatically for the virtual infrastructure. Using the RSN Tool, we can easily obtain a semantically valid dataset, which captures both physical characteristics of RF communications and business activities of tags’ movements. This is a major differentiation point of our work compared from previous works, which merely create the randomized dataset based on a set of virtual RFID readers. We also discuss a step-by-step usage of the RSN Tool from the creation of a virtual infrastructure to the generation of tag events. The experimental analysis shows that the RSN Tool can create the near-real dataset, which closely reflects business activities of the real RFID infrastructure.