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The study is aimed at establishing a neural network + PID feedback control FES (functional electrical stimulation) system used for adjusting the optimum electrical stimulating current to control the motion of an ankle joint. The proposed method further improves the drop-foot problem existing with hemiplegia patients.

Continuous arterial blood pressure monitoring is essential in monitoring patients during surgical operation or in intensive care units. In this study, we propose a new method to estimate beat-to-beat systolic blood pressure by combining the pulse arrive time and normalized pulse width measurement. The method was examined in nine patients who were in ICU. Results shows the new method has higher linearity (0.8218) and better precision (3.0775) than the methods using either pulse arrive time or pulse width only.

This study is aimed at establishing a neural network and fuzzy feedback control FES system used for adjusting the optimum electrical stimulating current to control the motion of an ankle joint. The proposed method further improves the drop-foot problem existing hemiplegia patients.

The motivation of this research is to improve the ability of ambulation for people with a certain degree of disability. The control method is using two tilt sensors as an input-controlling module. One of the tilt sensors detects the anterior/posterior tilting of the head and moves the wheelchair or mouse cursor forward/backward, the other distinguishes the left/right swing of the head. In order to increase the safety of this system, the M3S protocol established by the European Commission is also applied to this research. The system based on M3S protocol has the advantage of real-time monitoring for people with severe disabilities.

A novel laser Doppler flowmetry scheme is reported that adjusts the processing bandwidth adaptively to optimise the estimation of flow. To obtain an adequate processing bandwidth, the Doppler spectra is first fitted to the Lorentzian function, and the bandwidth at half the maximum of the Lorentzian function is used as an indicator of the major frequency range of the signal. The processing bandwidth is then tuned accordingly, and a frequency-weighted algorithm is applied to compute the fluid velocity. To investigate the influence of the processing bandwidth, an in vitro experiment was performed. In the experiment, the flow rate was controlled at constant velocity in the range from 0 to 18.52 mm s(-1), and the fluid velocity indices were calculated using adaptive and fixed processing bandwidths, respectively. The results showed that the adaptive processing bandwidth adjustment, not only significantly reduced the biological zero (9.6% of the case using 100 kHz bandwidth), but also enhanced the sensitivity of the laser Doppler measurement (over 20%) and linearly responded to a wider velocity range (R2 = 0.979 for velocity from 0 to 18.52 mm s(-1)).

This study is aimed at establishing a neural network and fuzzy feedback control FES system used for adjusting the optimum electrical stimulating current to control the motion of an ankle joint. The proposed method further improves the drop-foot problem existing in hemiplegia patients. The proposed system includes both hardware and software. The hardware system determines the patient's ankle joint angle using a position sensor located in the patient's affected side. This sensor stimulates the tibialis anterior with an electrical stimulator that induces the dorsiflexion action and achieves the ideal ankle joint trace motion. The software system estimates the stimulating current using a neural network. The fuzzy controller solves the nonlinear problem by compensating the motion trace errors between the neural network control and actual system. The control qualities of various controllers for four subjects were compared in the clinical test. It was found that both the root mean square error and the mean error were minimal when using the neural network and fuzzy controller. The drop-foot problem in hemiplegic's locomotion was effectively improved by incorporating the neural network and fuzzy controller with the functional electrical simulator.

This study proposes a new head-orientated wheelchair design for people with disabilities. This study involves a tilt sensor module fitted onto the operator's headgear that will sense head movements used to control the wheelchair's direction and speed.

This study proposes image processing and microprocessor technology for use in developing a head movement image (HMI)-controlled computer mouse system for the spinal cord injured (SCI).The system controls the movement and direction of the mouse cursor by capturing head movement images using a marker installed on the user's headset. In the clinical trial, this new mouse system was compared with an infrared-controlled mouse system on various tasks with nine subjects with SCI.The results were favourable to the new mouse system. The differences between the new mouse system and the infrared-controlled mouse were reaching statistical significance in each of the test situations (p0.05).The HMI-controlled computer mouse improves the input speed. People with disabilities need only wear the headset and move their heads to freely control the movement of the mouse cursor.

A computer-assisted and foot switch controlled functional electrical stimulation (FES) system was developed to present to walking subject real-time stimulating to their muscle during gait training. The FES was controlled by foot switch placed on the heel of unaffected foot and as a trigger to stimulate the muscles of the affected side. The purpose was to compare the effectiveness of this new developed system to a focused program of physical therapy for gait. Twelve hemiplegic patients were randomly assigned to either an experimental group (n=6) treated with the new developed FES system or a control group (n=6) treated with conventional physical therapy program. Gait analysis was obtained prior to and following every type of treatment. Stride length, walking velocity and functional ambulation category (FAC) were greatly increased in experimental group. A paired t-test revealed that differences in electromyography (EMG) of quadriceps and tibialis anterior muscles between patients' affected and unaffected sides were not significant after four-months training. It is concluded that a treadmill apparatus with a computer-assisted FES system controlled by foot switch is an effective tool for retraining gait in stroke patients.

A new infrared-controlled keyboard instead of the conventional computer keyboard was developed for those with hand dysfunction. The infrared transmitter with laser director was placed on the eyeglasses, and the keys of the conventional computer keyboard were all replaced by infrared receivers. In the infrared receivers we designed a modulized circuit to receive, demodulate and process the infrared signals. The modulized circuit used signal processing technique to convert the astable signal of the infrared receiver to a standard pulse train which could be used as control signal easily.

A new computer-aided biofeedback training system for cognitive rehabilitation in cerebral palsy was developed. It was very difficult for cerebral palsied children to handle entirely in the cognitive rehabilitation protocol. In this study, biofeedback training including light, sound, color images and other special functions can induce cerebral palsied children's interest in the rehabilitation protocol. Cognitive training is very much important to cerebral palsy patients in order that they may make decisions about their future. The purposes of this study are: (1) to develop a computer-based and low cost biofeedback (visual, audio) training system for cognitive rehabilitation. (2) to improve the reaction time and cognitive abilities of cerebral palsied children. Firstly, the system was tested by twenty normal children to make sure the system basic functions and could work normally. Then, it will be applied to cerebral palsied children for future clinical investigation.

This research reports on the development of a headset-type position sensors-controlled computer mouse for the disabled. This system may serve to assist those who suffer from spinal cord injuries or other handicaps to operate a computer. This system is composed of three major components: (A) the position sensor module; (B) the signal-processing module; and (C) a main controller, the Intel-8951 microprocessor. This concept of design is mainly based on the idea that the use of the position sensor module fastened to the headset could allow the convenient control of the operation of a computer mouse. Through this system, the disabled are competent for some types of work, such as a computer operator. The increase of opportunity to do a job for the disabled would help them live independently.

Although sacral anterior root neuromodulation (SARN) has proven to be effective in patients with neurogenic bladder, it is not widely accepted due to the need to conduct a dorsal rhizotomy, and commercially available SARN devices are not usually equipped with a closed-loop controller for the automatic regulation of bladder functions. Therefore, there is still a need for a more effective electrical neuromodulation scheme to restore bladder function. Intravesical pressure (IVP) is the major biosignal that reflects the state of bladder conditions. The present study develops a closed-loop control strategy for improving bladder emptying and verifies its performance using animal experiments. Two channel outputs of electrical currents triggered by IVP-feedback signals were set to automatically regulate a rat's pudendal nerve for selective nerve stimulation and blocking. Under this experimental design, a series of in vivo animal experiments were conducted on anesthetized rats, including the computational characterization of biosignals, the development of an intermittent high-frequency blocking current waveform for blocking the nerve, and verification of the control strategy. Results show that the IVP-feedback control strategy for dual-channel pudendal neuromodulation performed well in animal experiments and could be utilized to selectively stimulate and block the pudendal nerve to augment bladder contraction and restore external urethral sphincter bursting activity to improve bladder emptying. This study demonstrates the feasibility of the IVP-based feedback-control strategy with animal experiments. The results could provide a basis for developing a sophisticated neural prosthesis for restoring bladder function in clinical use or for neurophysiological study.

This study describes the motivation and the design considerations of an economical head-operated computer mouse. In addition, it focuses on the invention of a head-operated computer mouse that employs two tilt sensors placed in the headset to determine head position and to function as simple head-operated computer mouse. One tilt sensor detects the lateral head-motion to drive the left/right displacement of the mouse. The other one detects the head's vertical motion to move up and down with respect to the displacement of the mouse. A touch switch device was designed to contact gently with operator's cheek. Operator may puff his cheek to trigger the device to perform single click, double clicks, and drag commands. This system was invented to assist people with disabilities to live an independent professional life.

A closed-loop functional electrical stimulation (FES) system is developed to provide hemiplegic patients with a real-time stimulation to their muscles to prevent the drop-foot and the quadriceps weakness from happening during gait training. The FES is controlled by position sensors (ps) and triggered by footswitches (f) with real-time feedback. As the FES receives the signals from these sensors, it adjusts and outputs an optimum set of stimulation parameters automatically. One hemiplegic patient was recruited to conduct clinical evaluation and treated by using the new closed-loop FES system. It was revealed that the mean velocity, cadence, stride length, active ankle motion range, and functional ambulation category (FAC) improved significantly from 0.12 +/- 0.07 ms-1, 40.3 +/- 18.3 steps min-1, 0.35 +/- 0.10 m, 15 degrees, level 2 to 0.42 +/- 0.23 ms-1, 68.2 +/- 19.0 steps min-1, 0.70 +/- 0.22 m, 40 degrees, level 4 respectively for the patient. A paired t-test indicated that differences in the electromyography (EMG) of the tibialis anterior and the quadriceps muscles between the patient's disabled (affected side) foot and normal (unaffected side) foot are not significant (p > 0.05) after 12 weeks of training. It is concluded that this new closed-loop FES system is capable of providing this hemiplegic patient with restoration to regular walking after appropriate gait training. Future studies, including randomized-controlled study, should be implemented to document the efficacy of this system.