Sensory Feedback System Research Articles

物理エージェントシステム(PAS)におけるアーム用入力インターフェイスSensory Gloveの開発 : Sensory Gloveにおける感覚フィードバック系(ネットワーク/メディアロボティクス2)

物理エージェントシステム(PAS)におけるアーム用入力インターフェイスSensory Gloveの開発 : Sensory Gloveにおける感覚フィードバック系(ネットワーク/メディアロボティクス2)

Cerebellar structure and function: Making sense of parallel fibers

Many parts of the brain have to cooperate in a finely tuned way in order to generate coordinated motor output. Parameters of these cooperations are adjusted during early childhood development and years of motor learning later in life. The cerebellum plays a special role in the concert of these brain structures. With the unusual geometrical arrangement of its neuronal elements, especially of parallel fibers and Purkinje cells the cerebellum is a selective and sensitive detector of a specific class of spatio-temporal activity patterns in the mossy fiber system: sequences of excitatory input which ‘move’ along the direction of parallel fibers at about 0.5 m/s, i.e. the speed of spike conductance in parallel fibers. Precise spatio-temporal neuronal activity patterns have been shown to occur in two major sources of afference to the cerebellum, the neocortex and the sensory feedback system. Based on our own experimental work and the above-mentioned findings we suggest that the cerebellum detects specific spatio-temporal activity patterns which trigger learned cerebellar output related to motor control and which contributes to the control of precise timing of muscle contraction.

Opening doors with assistive technology.

Results of the 2001 RESNA student scientific paper and student design competitions are presented. The topics dealt with included: scapula orientation in a virtual wheelchair push; repeatability of determining effective Young's modulus of buttocks soft tissue across multiple subjects; power and control system testing of five different types of power wheelchairs; modification of hybrid III test dummy for use in wheelchair studies; effect of adult-onset diabetes and/or peripheral neuropathy on acceleration threshold detection during horizontal translations; battery tester for people with physical and mental disabilities; design of a modular sensory feedback system to enhance physical education of persons with disabilities; an assistive technology key turning device for independent entryway access; ear-chin strap system for sleep apnea.

Computer Simulation Study of Human Locomotion with a Three-Dimensional Entire-Body Neuro-Musculo-Skeletal Model. I. Acquisition of Normal Walking.

A model having a three-dimensional entire-body structure and consisting of both the neuronal system and the musculo-skeletal system was proposed to precisely simulate human walking motion. The dynamics of the human body was represented by a 14-rigid-link system and 60 muscular models. The neuronal system was represented by three sub-systems: the rhythm generator system consisting of 32 neural oscillators, the sensory feedback system, and the peripheral system expressed by static optimization. Unknown neuronal parameters were adjusted by a numerical search method using the evaluative criterion for locomotion that was defined by a hybrid between the locomotive energy efficiency and the smoothness of the muscular tensions. The model could successfully generate continuous and three-dimensional walking patterns and stabilized walking against mechanical perturbation. The walking pattern was more stable than that of the model based on dynamic optimization, and more precise than that of the previous model based on a similar neuronal system.

1P1-D04 物理エージェントシステム (PAS) におけるロボットアームを用いた感覚フィードバックに関する基本検討

遠隔操縦型ロボットをエージェントとして, 遠隔地の人間同士の協調作業を支援するロボットシステムを(PAS)と呼ぶ。PASにおける, ロボットアームの操作人力インターフェイスとして, 新たにグローブ機構「Sensory Glove」を製作し, これを用いて, 遠隔地のロボットアームを直感的に操作することを可能とした。また, 遠隔地のロボットアームが得た力覚, 触覚情報を操作者にフィードバックすることで, 遠隔地との, より確かな空間情報共有操作の実現を目指す。

Strategies for providing upper extremity amputees with tactile and hand position feedback – moving closer to the bionic arm

A continuing challenge for prostheses developers is to replace the sensory function of the hand. This includes tactile sensitivity such as finger contact, grip force, object slippage, surface texture and temperature, as well as proprioceptive sense. One approach is sensory substitution whereby an intact sensory system such as vision, hearing or cutaneous sensation elsewhere on the body is used as an input channel for information related to the prosthesis. A second technique involves using electrical stimulation to deliver sensor derived information directly to the peripheral afferent nerves within the residual limb. Stimulation of the relevant afferent nerves can ultimately come closest to restoring the original sensory perceptions of the hand, and to this end, researchers have already demonstrated some degree of functionality of the transected sensory nerves in studies with amputee subjects. This paper provides an overview of different types of nerve interface components and the advantages and disadvantages of employing each of them in sensory feedback systems. Issues of sensory perception, neurophysiology and anatomy relevant to hand sensation and function are discussed with respect to the selection of the different types of nerve interfaces. The goal of this paper is to outline what can be accomplished for implementing sensation into artificial arms in the near term by applying what is present or presently attainable technology.

形状記憶合金薄膜アクチュエータの力学特性と制御

So far, the researches on SMA (= shape memory alloy) thin film micro actuator for micro machine were reported about the metallurgical aspect, the sputter deposit process and the fabrication of devices with the SMA thin film. However the properties of SMA thin film as servo actuator has not been studied. On the other hand, the several characteristics of bulk SMA wire actuators to control it had been studied. In this paper, based on the same aspect as the bulk SMA wire actuator, the dynamical properties, the mathematical model and control of SMA thin film actuator were investigated experimentally. As the results, the summary is as follows. 1) The mathematical model of output force of SMA thin film actuator is expressed as the nonlinear and continuous function of temperature and strain. 2) The above function is found linearizable. Thus the linear mathematical model was obtained. 3) Tensile force could be controlled by the force sensor feedback system of the SMA thin film actuator.

皮膚振動刺激による筋電義手感覚フィードバック装置の検討

皮膚振動刺激による筋電義手感覚フィードバック装置の検討

Walking when utilizing a sensory feedback system and an electrical muscle stimulation gait orthosis

Electrical muscle stimulators (EMS) have been combined with a reciprocating gait orthosis (RGO) to produce an EMS-RGO system for constant velocity ambulation exercise in a spinal cord injured (SCI) individual. The objective of this study is to evaluate an auditory feedback system (AFS) used by the SCI subject when ambulating with the EMS-RGO. Three different types of auditory signals (M = metronome alone, MSL = metronome plus stride length information, and NONE = no auditory feedback) were examined at three different constant walking velocities (WV1 = 0.64 kph, WV2 = 1.22 kph, and WV3 = 1.80 kph). The experimental design was 3 × 3 full factorial with repeated measures, and the dependent variable was the absolute error (AE) of walking distance (absolute value of the distance the subject walked in one minute subtracted from the target distance). A block diagram and circuit schematic of the AFS is provided. The results indicate that at WV1 there is no significant difference of AE among the three auditory conditions (M, MSL and NONE). At WV2, the AE for the NONE auditory condition is significantly greater than the AE for M and MSL ( p < 0.05). At WV3, the AE for the NONE auditory condition is significantly less than the AE for M and MSL ( p < 0.05). Finally, there was no significant difference in AE between both the M and MSL auditory conditions at any of the three walking velocities. This study indicates that an adequate sensory feedback system for constant velocity control of ambulation in this SCI subject consists of metronome only auditory feedback. Since there is some complexity in determining when the NONE condition should be utilized in progressive velocity walking, it is preferable to retain metronome alone auditory feedback for all walking velocities.

The role of hypoglossal sensory feedback during feeding in the marine toad, Bufo marinus.

Behavioral observations demonstrate that bilateral deafferentation of the hypoglossal nerves in the marine toad (Bufo marinus) prevents mouth opening during feeding. In the present study, we used high-speed videography, electromyography (EMG), deafferentation, muscle stimulation, and extracellular recordings from the trigeminal nerve to investigate the mechanism by which sensory feedback from the tongue controls the jaw muscles of toads. Our results show that sensory feedback from the tongue enters the brain through the hypoglossal nerve during normal feeding. This feedback appears to inhibit both tonic and phasic activity of the jaw levators. Hypoglossal feedback apparently functions to coordinate tongue protraction and mouth opening during feeding. Among anurans, the primitive condition is the absence of a highly protrusible tongue and the absence of a hypoglossal sensory feedback system. The hypoglossal feedback system evolved in parallel with the acquisition of a highly protrusible tongue in toads and their relatives.

Design and evaluation of a sensory feedback system that provides grasping pressure in a myoelectric hand

Providing accurate sensory information to the individual with a myoelectric limb is of great importance for improving device use in a wide variety of tasks. A number of feedback systems presently being investigated rely on either vibrotactile or electrotactile skin stimulation, which does not provide sensory patterns similar to those in a natural grasping hand. A prototype system was developed to enhance sensory information transfer by using a technique in which the feedback modality (pressure) was the same as the grasping pressure. The present study compared the developed system (pressure) with vibrotactile feedback, vision, and compounds of these three modes. It was found that the pressure-pressure concept reduced grasping pressure replication errors and error variability.

Walking while using a sensory tactile feedback system: potential use with a functional electrical stimulation orthosis

A major limitation in the utilization of a functional electrical stimulation (FES) orthosis for routine, daily standing and walking of the spinal-cord-injured person is that visual monitoring is required to maintain balance and the walking pace. For standing and walking to be continuous and automatic with such an orthosis, a closed-loop sensory feedback system is proposed and evaluated; it provides vibrotactile feedback as a substitute to one's own visual sensation. Eight blindfolded experimental subjects were utilized as ‘imitators’ to interpret the footfalls of a second person (the pace setter). The experimental objective was to test the hypothesis that sufficient information could be transferred by way of the sensory (tactile) feedback system to the ‘imitator’ and to determine effectively foot position and anticipate the next step of the pacesetter. Quantitative analysis evaluated the effect of three different levels of training, under two different levels of cognitive load. The results disclosed a significant improvement in subject performance at the higher training levels compared with the ‘no training’ level ( P = 0.01). Neither the cognitive load nor the interaction of training and cognitive load altered significantly the effect of training on subject performance. The experimental hypothesis is therefore satisfied that sufficient information was indeed transferred using the apparatus described. Such information (when utilized in conjunction with a thorough training programme) could be used in a practical sense by a paraplegic individual to interpret his own foot steps. Through continued use and training, it is likely that this information could become subconscious and automatic. Therefore, the spinal-cord-injured person would walk with an FES orthosis in various environments and minimize or remove their reliance on visual sensory information.

Control of articulated robot arm with sensory feedback: laser beam tracking system

A method for the trajectory tracking control of an articulated robot arm using sensory feedback is presented. First, a general control algorithm for such a problem is presented. To implement sensory feedback effectively, the dynamics of a robot arm is described in the task coordinate system. Then the dynamics of the robot arm in the task coordinate system are linearized using nonlinear feedback. Because the linearization cannot be done completely because of variations and identification errors of the physical parameters of a robot arm, a robust controller is designed so that the effect of parameter variations and errors can be lessened. The control law is shown to be simplified by the use of high-gain feedback. The simplification can make the implementation of the control law very easy. The proposed algorithm is applied to the trajectory-tracking control of an articulated robot arm using a laser beam. The experiments show that the proposed algorithm works well for such a sensory feedback system. >

Multisensor fusion and navigation of mobile robots

Navigation and motion control of autonomous mobile robots require an on-line, real-time sensory feedback system to guide robots to stay on planned path, to avoid unexpected obstacles, to return to planned path if a detour is necessary, and even to replan the path. This problem is a difficult one, because of incomplete world knowledge and unknown obstacles. A spherical sensory model similar to human perception is presented. Its spherical octree data structure provides an efficient and unified representation scheme for multisensor fusion, navigation, motion control, and spatial reasoning.

Neurochemical investigation of the afferent pathway from the vagus nerve to the nucleus tractus solitarius in mediating the “satiety syndrome” induced by systemic cholecystokinin

The satiety syndrome induced by intraperitoneally administered cholecystokinin (CCK) requires an intact visceral sensory feedback system involving the afferent vagus nerve [5, 22, 33] and the nucleus tractus solitarius (NTS) [9, 10]. Since both the vagus and the NTS contain CCK [25,37], the vagal-NTS synapse could conceivably employ CCK as a transmitter. To test this hypothesis, CCK was injected directly into the NTS region in awake rats. CCK at doses of 1 ng, 10 ng, and 100 ng had no effect on food consumption or exploratory behaviors associated with the satiety syndrome. The acetylcholine agonist carbachol, injected directly into the NTS region, effectively mimicked the actions of intraperitoneally administered CCK on feeding and exploration. These data suggest that CCK is not the transmitter at the vagal-NTS site in the visceral sensory pathway projecting to brain regions mediating the reduced feeding and exploration actions of systemic CCK.

Laser·based arc welding sensor monitors weld preparation profile

Automation of arc welding jobs is accelerating rapidly now that sensory feedback systems are beginning to become available. However, many of these systems have limited capabilities. A new laser‐based optical profile sensor developed in Holland not only tracks all types of seams but also modifies weld process parameters on the basis of profile information.

Interaction of sensory feedback: a child-adult comparison of oral sensory and temporal articulatory function.

Recent studies have demonstrated a systematic increase in lingual sensory thresholds and a temporal articulatory reorganization in subjects speaking under exposure to auditory masking. These data suggest that auditory and lingual sensory feedback systems exist in a balanced interaction specific to the oral articulations involved in speech production. The present study attempted to gain additional information on this proposed interaction. Lingual sensory and temporal articulatory measurements were obtained from 10 adults and 10 children under each of four feedback conditions: (1) normal feedback, (2) exposure to binaural auditory masking during speech, (3) topical application of anesthesia to the lingual dorsum prior to speech, and (4) combined masking and anesthesia. Analysis indicated that children had lower lingual sensory thresholds than adults in all conditions and that they were more susceptible to the disruption of auditory feedback. Also, measurements of durations of vowels indicated no age-related differences with durations in both groups increasing when auditory feedback was impaired.

Training program for a myo-electrically controlled prosthesis with sensory feedback system.

A myo-electrically controlled prosthesis that incorporates a sensory feedback mechanism to provide the wearer with a sense of touch or gripping force in the prosthetic hand was developed for patients with below-elbow amputations. A training protocol was established in which patients were taught to produce myo-electric control signals and to interpret the sensory feedback. The protocol includes functional training in daily living skills. The experiences of four patients trained with these limbs are described.

Ideas on sensory feedback in hand prostheses.

Development of systems for sensory feedback in hand prostheses has not been as successful as that of modern prosthesis control systems. The discrepancy is partly caused by an insufficient analysis of the concept of sensory feedback and by neglect of knowledge on the physiology of kinesthesis. In the present paper modern theories on physiologic kinesthesis are briefly summarized and the implication of these theories on the development of prosthesis sensory feedback systems are discussed. It is concluded that the future development of sensory feedback systems for hand prostheses should be directed towards increased utilization of the physiologic kinesthesis resulting from operation of the prosthesis control systems. This can be obtained by further development of the control systems. One promising approach in this direction is the use of a proportional control signal based on signal acquisition through pattern recognition of multiple myoelectric signals. Development of artificial systems for feedback should be restricted to situations when feedback emerging from the prosthesis control is insufficient. The importance of simplicity and reliability of feedback systems is stressed as well as the necessity to maintain prosthesis self-containment even after application of a feedback system.

Development of Sensory Feedback System for the Lower Prosthesis

Development of Sensory Feedback System for the Lower Prosthesis