Chandan Kumar Jha
@iitgn.ac.in
Research Scholar, Electrical Engineering
IIT Gandhinagar
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Chandan Kumar Jha, Yagna Shukla, Rupsha Mukherjee, Prakash Rathva, Mahima Joshi, and Dhruv Jain
Institute of Electrical and Electronics Engineers (IEEE)
Recent studies have shown that virtual gamified therapy can be a potential adjunct to conventional orthopedic rehabilitation. However, the off-the-shelf gaming consoles used for virtual rehabilitation pose several practical challenges in deploying them in clinical settings. In this paper, we present the design of a portable glove-based virtual hand rehabilitation system (RehabRelive Glove) that can be used at both clinics and homes for physiotherapy. We also evaluate the system's efficacy on patients with post-traumatic hand injuries. Thirty patients were randomly categorized into groups A (virtual rehabilitation) and B (conventional physiotherapy). Both groups received fifteen 25-minute sessions of respective therapy over three weeks. The wrist and finger joints' range of motion (ROM) and grip strength were measured every seven sessions to compare the efficacy. Group A showed about 1.5 times greater improvement in flexion/extension ROM of the wrist compared to Group B. While both groups improved finger ROM and grip strength with time, no significant difference was observed between the groups. The results suggest that the proposed virtual rehabilitation system effectively enables patients with hand injuries to recover ROM faster.
Chandan Kumar Jha, Kuldeep Jajoria, Arup Lal Chakraborty, and Himanshu Shekhar
Institute of Electrical and Electronics Engineers (IEEE)
Fiber Bragg gratings (FBGs) are a potential alternative to piezoelectric ultrasound sensors for applications that demand high sensitivity and immunity to electromagnetic interference (EMI). However, limited data exist on the quantitative performance characterization of FBG sensors in the MHz frequency range relevant to biomedical ultrasound. In this work, we evaluated an FBG to detect MHz-frequency ultrasound and tested the feasibility of measuring passive cavitation signals nucleated using a commercial contrast agent (SonoVue). The sensitivity, repeatability, and linearity of the measurements were assessed for ultrasound measurements at 1, 5, and 10 MHz. The bandwidth of the FBG sensor was measured and compared to that of a calibrated needle hydrophone. The FBG showed a sensitivity of 0.99, 0.769, and 0.818 V/MPa for 1, 5, and 10 MHz ultrasound, respectively. The sensor also exhibited linear response ( $0.975\\leq {R}$ -Squared ≤ 0.996) and good repeatability with a coefficient of variation (CV) less than 5.5%. A 2-MHz focused transducer was used to insonify SonoVue microbubbles at a peak negative pressure of 175 kPa and passive cavitation emissions were measured, in which subharmonic and ultraharmonic spectral peaks were observed. These results demonstrate the potential of FBGs for MHz-range ultrasound applications, including passive cavitation detection (PCD).
Kuldeep Jajoria, Chandan Kumar Jha, Arup Lal Chakraborty, and Himanshu Shekhar
IEEE
In this paper, we present the characterization of an FBG sensor to detect ultrasound in the MHz frequency range which is used in biomedical ultrasound. The linearity, sensitivity, and repeatability of the sensor were tested at 1 MHz, 5 MHz, and 10 MHz in the peak acoustic rarefactional pressure range of 0-1.2 MPa. The FBG showed good linearity (R-Squared=0.98), high sensitivity (0.82 V/MPa at 10 MHz), and high repeatability (coefficient of variation ≤ 5.5%). Our results show the potential of FBG sensors to detect ultrasound for biomedical applications.
Kahkashan Bansal, Chandan Kumar Jha, Dhiraj Bhatia, and Himanshu Shekhar
American Chemical Society (ACS)
The role of ultrasound in medicine and biological sciences is expanding rapidly beyond its use in conventional diagnostic imaging. Numerous studies have reported the effects of ultrasound on cellular and tissue physiology. Advances in instrumentation and electronics have enabled successful in vivo applications of therapeutic ultrasound. Despite path breaking advances in understanding the biophysical and biological mechanisms at both microscopic and macroscopic scales, there remain substantial gaps. With the progression of research in this area, it is important to take stock of the current understanding of the field and to highlight important areas for future work. We present herein key developments in the biological applications of ultrasound especially in the context of nanoparticle delivery, drug delivery, and regenerative medicine. We conclude with a brief perspective on the current promise, limitations, and future directions for interfacing ultrasound technology with biological systems, which could provide guidance for future investigations in this interdisciplinary area.
Chandan Kumar Jha, Kshitij Gajapure, and Arup Lal Chakraborty
Institute of Electrical and Electronics Engineers (IEEE)
This paper demonstrates a fiber Bragg grating sensor-based instrumented glove that simultaneously measures the range of motion of the ten finger joints (five metacarpophalangeal, four proximal interphalangeal and one interphalangeal joint) with very high angular resolution (0.1°). The accuracy and repeatability of all the ten sensors of the glove are compared with a pre-calibrated inertial measurement unit (IMU) sensor. The glove outperforms many earlier reported sensing gloves with a mean error of 0.80°. The standard deviation (1.01°) and range (2.60°) obtained in the reliability test performed on five healthy subjects are also smaller compared to many other gloves. The feasibility of using the glove in real-world applications has been shown by demonstrating a virtual reality (VR) platform that uses a Raspberry Pi-based module to interface the glove with custom VR games running on an Android tablet or a VR headset. VR-based gaming platforms have become popular in the rehabilitation of the upper limb in stroke patients in recent years. The high accuracy and reliability of this glove will enable accurate tracking of the movement quality and recovery progress of stroke patients during the virtual rehabilitation therapy.
Chandan Kumar Jha, Oindrila Sinha, and Arup Lal Chakraborty
IEEE
The dicrotic notch is an important feature in the arterial pressure waveform that marks the end of the ventricular ejection. Reliable detection of this notch in the pulse waveform is of interest in the investigation of cardiovascular disorders. It also provides insights into haemodynamic complexities of critical patients. We demonstrate a fiber Bragg grating (FBG) sensor-based arterial pulse signal recording system that precisely detects the dicrotic notch as well as the pre-dicrotic notch. The notches were clearly visible on the pulse waveform recorded from four different subjects. The sensor is sensitive enough to pick up the pulse signals even when it was attached as far as 10 cm from the wrist joint. FBG sensors being lightweight and immune to electromagnetic interference, are ideally suited for use in hospital settings. The complete system can readily be made compact, battery-powered, and wearable.
Chandan Kumar Jha and Arup Lal Chakraborty
IEEE
Virtual reality-based exercises being immersive and interactive have become a useful tool in the rehabilitation of stroke survivors. Input systems such as instrumented gloves used in VR systems must be accurate, highly repeatable, and have very low latency to make the VR environment immersive. This paper describes an FBG sensor-based glove that offers very high accuracy (error = 0.80°) and excellent repeatability (standard deviation = 0.95°) in measuring the ten finger joint angles of the human hand simultaneously. The accuracy and repeatability of six of these sensors attached on the glove were tested using a pre-calibrated inertial measurement unit sensor.
Chandan Kumar Jha, Shivang Agarwal, Arup Lal Chakraborty, and Chinmay Shirpurkar
Institute of Electrical and Electronics Engineers (IEEE)
We demonstrate a fiber Bragg grating (FBG) sensor-based highly accurate instrumented glove that can measure finger flexure with an angular resolution of 0.1<inline-formula><tex-math notation="LaTeX">$^{\\circ }$</tex-math></inline-formula>. The sensing unit consists of an FBG that is very sensitive to axial strain induced by the flexing of fingers. The spectral shift of the reflection spectrum of the FBG varies linearly with the joint rotation angle. The sensor offers a very high angular resolution of 0.1<inline-formula><tex-math notation="LaTeX">$^{\\circ }$</tex-math></inline-formula> with a very high sensitivity of 18.45 pm/degree. The accuracy evaluated using a mechanical setup, and the human hand is 0.13<inline-formula><tex-math notation="LaTeX">$^{\\circ }$</tex-math></inline-formula> and 0.67<inline-formula><tex-math notation="LaTeX">$^{\\circ }$</tex-math></inline-formula>, respectively. This is much better than many other reported sensors. The sensor showed excellent repeatability with a maximum standard deviation of 0.30<inline-formula><tex-math notation="LaTeX">$^{\\circ }$</tex-math></inline-formula> and 0.79<inline-formula><tex-math notation="LaTeX">$^{\\circ }$</tex-math></inline-formula> on a mechanical setup and the human hand, respectively. The results are validated using a precalibrated inertial measurement unit (IMU) sensor. The sensor also exhibited much better dynamic response compared to the IMU upto a rotation speed of 80<inline-formula><tex-math notation="LaTeX">$^{\\circ }$</tex-math></inline-formula>/s. These results demonstrate that our sensor is a strong potential candidate for the development of high-accuracy instrumented gloves that could be used to monitor the progress in the rehabilitation of stroke survivors. This paper focuses on the careful characterization of the sensor to establish it as a sensitive and practical approach. The accuracy, repeatability, and dynamic response were evaluated using a motorized mechanical model of a finger joint and also on the hands of two human subjects.
Chandan Kumar Jha and Arup Lal Chakraborty
IEEE
Accurate measurement of finger joint angles is very important in the fields such as rehabilitation, bionics, etc. In this paper, we present a fiber Bragg grating (FBG) sensor-based flexure sensing glove to measure the finger joint angles with high accuracy. We evaluate its accuracy and repeatability on four human subjects by measuring their proximal interphalangeal (PIP) joint angles of the index, middle and the ring fingers. Our glove showed excellent agreement (R-Squared: 0.9985) with the inertial measurement unit (IMU) sensor readings. The glove outperforms several existing sensors exhibiting a maximum error (1.42 degrees), mean error (0.45 degrees) and maximum standard deviation (0.56 degrees). In the future, the study will be extended to all the joints.
Chandan Kumar Jha, Arup Lal Chakraborty, and Shivang Agarwal
OSA
We demonstrate an FBG-based flexure sensing glove with virtual reality interface that has high accuracy (0.40°) and sensitivity (18.45 pm/degree), very linear response and excellent dynamic performance compared to an inertial measurement unit sensor.
Anirban Roy, Arup Lal Chakraborty, and Chandan Kumar Jha
The Optical Society
This paper demonstrates a technique of high-resolution interrogation of two fiber Bragg gratings (FBGs) with flat-topped reflection spectra centered on 1649.55 nm and 1530.182 nm with narrow line width tunable semiconductor lasers emitting at 1651.93 nm and 1531.52 nm, respectively. The spectral shift of the reflection spectrum in response to temperature and strain is accurately measured with a fiber-optic Mach-Zehnder interferometer that has a free spectral range of 0.0523 GHz and a broadband photodetector. Laser wavelength modulation and harmonic detection techniques are used to transform the gentle edges of the flat-topped FBG into prominent leading and trailing peaks that are up to five times narrower than the FBG spectrum. Either of these peaks can be used to accurately measure spectral shifts of the FBG reflection spectrum with a resolution down to a value of 0.47 pm. A digital signal processing board is used to measure the temperature-induced spectral shifts over the range of 30°C-80°C and strain-induced spectral shifts from 0 μϵ to 12,000 μϵ. The shift is linear in both cases with a temperature sensitivity of 12.8 pm/°C and strain sensitivity of 0.12 pm/μϵ. The distinctive feature of this technique is that it does not use an optical spectrum analyzer at any stage of its design or operation. It can be readily extended to all types of tunable diode lasers and is ideally suited for compact field instruments and for biomedical applications in stroke rehabilitation monitoring.
Anirban Roy, Arup Lal Chakraborty, and Chandan Kumar Jha
SPIE
This paper demonstrates the interrogation of a fiber Bragg grating with a flat-topped reflection spectrum centred on 1649.55 nm using only a single mode tunable 1651.93 nm semiconductor laser and a fiber ring resonator. The Bragg shift is accurately measured with the fiber-optic ring resonator that has a free spectral range (FSR) of 0.1008 GHz and a broadband photo-detector. Laser wavelength modulation and harmonic detection are used to transform the gentle edges of the flat-topped FBG spectrum into prominent leading and trailing peaks, either of which can be used to accurately measure spectral shifts of the FBG reflection spectrum with a resolution of 0.9 pm. A Raspberry Pi-based low-cost embedded processor is used to measure the temperature-induced spectral shifts over the range 30°C–80°C. The shift was linear with a temperature sensitivity of 12.8 pm/°C. This technique does not use an optical spectrum analyzer at any stage of its design or operation. The laser does not need to be pre-characterized either. This technique can be readily extended to all types of tunable diode lasers and is ideally suited for compact field instruments.