5th Joint Seminar on Rehabilitation Engineering and Assistive Technology

5th Joint Seminar on Rehabilitation Engineering and Assistive Technology

Neural Electronic Engineering Laboratory
Division of Biomedical Engineering for Health and Welfare
Graduate School of Biomedical Engineering
Tohoku University
Sendai, Japan

Biocybernetics Laboratory
Department of Biomedical Engineering
Institut Teknologi Sepuluh Nopember (ITS)
Surabaya, Indonesia

Schedule:
Date: May 8, 2023
Time: 13.00 Surabaya /15.00 Sendai
Venue: Online (Zoom Meeting)

Presentation list:
1) “A Study on Estimation of Stride Length and Walking Speed in Abnormal Walking Using A Lower Leg Inertial Sensor,” Sanayuki Hasegawa, Takashi Watanabe
2) “Design of Information System for Remote Rehabilitation with Live Video Stream using PTZ Camera,” Seno Aji Darmawan, Achmad Arifin, Norma Hermawan
3) “Fundamental Study on the Effect of Catch-like Inducing Stimulation on Ankle Dorsiflexion Angle,” Rina Yamada, Takashi Watanabe
4) “Fuzzy-PID Control Scheme of Robotic Rehabilitation for Elbow Joint Movements,” Sintong Mangaraja Sidabalok, Achmad Arifin, Josaphat Pramudijanto, Hendra Kusuma, Andra Risciawan, Moh Ismarintan Zazuli

A Study on Estimation of Stride Length and Walking Speed in Abnormal Walking Using A Lower Leg Inertial Sensor

Sanayuki Hasegawa*, Kanta Akatsuka**, Takashi Watanabe**

* Graduate School of Engineering, Tohoku University, Japan

** Graduate School of Biomedical Engineering, Tohoku University, Japan

Abstract

Variability in stride length can be used to assess the progression of Parkinson’s disease, and walking speed can be used to predict the risk of adverse events in the elderly. This study focused on using a single inertial sensor attached on the shank in order to estimate stride length and walking speed of abnormal gait. One cause of estimation error in stride length and walking speed is the accumulation error that occurs when the acceleration is integrated. Therefore, in a previous study using a lower leg sensor, the accumulated error was removed by linearly correcting the shank movement velocity at the time of vertical events as 0 m/s, in which the vertical event was detected by using the peak value (the value closed to 0 deg/s) of angular velocity in the sagittal plane of the stance phase. Here, correction value of the velocity was calculated by applying the inverted pendulum model, that is it was calculated using the fact that the lower leg moves in a circular motion around the ankle at the time of vertical event. However, the shank movement velocity at the time of the vertical event is not 0 m/s generally. In addition, the error correction method was not tested in abnormal gait. Therefore, in this study, the vertical event detection method was modified, and tested in gait of healthy subjects and simulated hemiplegic gaits. The modified method, first, determined detectable section of the vertical event using the difference between measured acceleration and the calculated acceleration from measured angular velocity. Then, the point when angular velocity in the sagittal plane is closest to 0 deg/s in the detectable section was determined as the vertical event. The accuracy of the estimated stride length and walking speed in this study were better than the method using the foot sensor with ANN movement detection method developed in our research group and the method using a lower leg sensor in the previous study for normal walking and simulated hemiplegic gait (simulated circumduction gait and simulated steppage gait). In addition, in the hemiplegic simulated gaits, estimated errors in walking speed did not exceed the minimum clinically important difference (MCID). This showed the usefulness of the stride length estimation method using the inertial sensor of the shank and the inverted pendulum model in normal and simulated hemiplegic gait.

Design of Information System for Remote Rehabilitation with Live Video Stream using PTZ Camera

Seno Aji Darmawan, Achmad Arifin, Norma Hermawan

Biomedical Engineering Department, ITS, Surabaya, Indonesia

Abstract

Remote rehabilitation is an effort to help patients with difficulty to attend to rehabilitation center, or problem of availability of medical rehabilitation staff in small healthcare delivery institutions. Rehabilitation systems such as Functional Electrical Stimulation (FES), or Robotic Rehabilitation can be operated on-site of patients to deliver rehabilitation to motor disorder patients and monitored by medical rehabilitation staff in real-time. In this research, an information system for remote rehabilitation of FES and upper limb robotic rehabilitation with live video streaming has been developed and tested. The information system design included web-based applications and database. The system has been tested for monitoring FES and upper limb robotic rehabilitation system in ITS. The system conveyed video data with acceptable delay and small packet losses. Integration with rehabilitation data (kinematical data, stimulation intensity, etc.) will be next development agenda.

A Fundamental study on the effect of catch-like inducing stimulation on ankle dorsiflexion angle

Lina Yamada, Takashi Watanabe

Graduate School of Biomedical Engineering, Tohoku University, Japan

Abstract

Foot drop is a common disabling impairment resulting from upper motor neuron lesions such as stroke. Functional electrical stimulation (FES) of the ankle dorsiflexor muscle during the swing phase of gait can correct foot drop. Compared with constant-frequency trains (CFTs), which are traditionally used during FES, catch-like inducing trains (CITs) have been shown to enhance muscle performance and reduce muscle fatigue. The purpose of this study was to investigate the effect of CITs on ankle dorsiflexion during swing phase in relation to muscle fatigue and ankle angles. Ankle dorsiflexion was electrically elicited with participants seated and the foot hanging freely. For stimulation protocol 1, CFTs (20 Hz frequency train) and CITs (IPI 10ms at the onset of 20 Hz frequency trains) were applied for 15 minutes. The muscle fatigue tests were conducted before and after 15-minute stimulation trials. For stimulation protocol 2, in addition to CFTs, CITs (IPI 10ms at the onset of 20 Hz frequency trains) and CITs2 (IPI 10ms at the onset and 600ms after the onset of 20 Hz frequency trains) were applied for one minute. The ankle angles during each stimulation were compared. CITs produced a greater increase in ankle dorsiflexion and managed to maintain a greater angle than CFT after 15 minutes. The time reaching of the target angle was quicker when CIT was applied. In addition, by adding a single pulse in the middle of the stimulation-on period, a greater angle was generated at the offset of stimulation which is expected to be the heel contact phase during gait cycle.

Fuzzy-PID Control Scheme of Robotic Rehabilitation for Elbow Joint Movements

Sintong Mangaraja Sidabalok¹, Achmad Arifin¹, Josaphat Pramudijanto¹, Hendra Kusuma², Andra Risciawan³, Moh Ismarintan Zazuli²

¹Biomedical Engineering Department, ITS, Surabaya, Indonesia

2 Electrical Engineering Department, ITS, Surabaya, Indonesia

3Manurfaktur Robot Indonesia (MRI), Surabaya, Indonesia

Abstract

Spasticity is a motor disorder that appears in post-stroke patients as a result of damage to the upper motor neuron syndrome, when stroke patients are guided in stretching their upper extremity muscles, muscle contractions appear against the direction of the passive movement being carried out. One of the rehabilitation technologies for stroke patients is the exoskeleton to train subject with repetitive movements. An exoskeleton with PID control is not enough in determining the target of movements due to differences of initial characteristics among subjects, such as Range of Motion (ROM), and change of neuro-musculo-skeletal system characteristics during rehabilitation, etc. An additional control method was designed in the form of Fuzzy System which determines the exoskeleton’s movement target based on input from the torque obtained by the load cell pressure sensor and the position of the encoder. The experiment was carried out on normal subjects with scenarios that resembled the conditions of stroke patients.  The fuzzy system was able to process the given input to determine the appropriate output. The results of this test show that the scenario test that has been carried out has succeeded in detecting spasticity with a percentage of 98.12% accuracy. Experimental tests with paralyzed subjects are needed to verify the fuzzy system performance in responding to change of subjects’ characteristics due to rehabilitation benefits.