A temperature compensated optical fibre bending sensor for physiological measurement

peer-reviewedThe light attenuation measurement of a plastic optical fibre sensor based on a referenced intensity modulation technique with respect to different input voltage level and room temperature has been investigated. The results show that light attenuation at the sensor output and reference output are dependent on the source (LED) drive current and temperature, but the output ratio is small and tolerable for this application. This is significant for bending monitoring applications using optical fibre sensor based on intensity modulation, providing a more reliable technique based on power and temperature compensation.PUBLISHEDpeer-reviewe

Optical goniometer for knee joint angle continuous monitoring

Knee joint is an important part of human body. People with poor knee condition generally have limited physical movement, rendering to mental stress and agony. Current technology to support the knee diagnosis and treatment procedures are limited to the use of manual goiniometer, x-ray and magnetic resonance imaging (MRI). X-ray and MRI technologies are useful to have some insight on the knee problem, but they are not applicable for continuous monitoring. One of the key methods used by physiotherapist to assess knee health condition is by measuring knee joint angle during gait and identify the angular range for the knee movement of the patient in the frontal plane

Review of human joint monitoring devices: conventional vs. Optical fibre based sensors

Health monitoring devices are highly demanded in order to determine patients’ health condition, to monitor the health recovery progress, and to help the physiotherapist during rehabilitation period of a patient. This paper is focused on knee joint assessment devices and technology implementation. Knee joint angle measurement devices includes many devices such as accelerometer, electro-goniometer, torsiometer, acoustic, visual sensory, and optic fibre. There are several limitations to these technologies which require improvements. Many of the existing techniques and technologies are becoming conventional and there is a need to identify and to explore better methods to enhance the limitations of existing devices. The need of technologies with higher accuracy, reliability, and lower cost have always been a crucial factor. In this paper, a study of conventional and latest technologies are reviewed, and suggested to further explore the implementation of optical fibre based technology for the above-mentioned application. Optical fibre device has faster response, better accuracy, lighter in weight, lower cost, and is not effected by external physical variable such as electromagnetic waves as compared to conventional sensors

Mathematical representation of joint angle measurement using step index optic fibre and linear array photodiode sensor

Human joint angle measurement involves various applications, for example monitoring of spine movement in sagittal and frontal planes, upper limb motion such as shoulder, neck and elbow, as well as lower limb motion such as hip, knee, and ankle. As the range of motions of different human joints are not similar, the output estimation of the designed sensor for these applications need to be carried out prior to sensor development. In this paper, the conceptual design of low-cost plastic optical fibre based on single step index fibre is illustrated, the mathematical modelling is explained, and the sensor’s hardware assemble is designed using CATIA software, before the estimated sensor output is presented. These results will be used as a reference values for actual optical fibre sensor design in the near future

Knee monitoring device based on optical sensor embedded in mechanical compartment assembly

Development of various health monitoring devices for health monitoring applications such as spine monitoring, respiration rate, heart rate, as well as upper and lower limb motion detections are at increasing rate. The use of optical fiber-based devices provides significant contribution in this area due to their advantages such as immunity to electromagnetic interference, lightweight and possibly small sensor setup. However, the application of intensity-based optical fiber sensor for human joint motion detections resulted in limited detection angle, where most sensor are not able to detect more than 90 deg. angle. To improve this limitation, we propose an optical sensor approach with mechanical-assisted components assembly that translates angular movement to linear movement. The light detection on the photodiode array at different pixels is analyzed to represent the angle movement of the knee. Based on our study, the proposed device can be applied to detect angle between 0−160° with an accuracy of 0.08°. The obtained results make it possible to apply this technique as knee monitoring device

Optical goniometer for knee joint angle continuous monitoring

Knee joint is an important part of human body. People with poor knee condition generally have limited physical movement, rendering to mental stress and agony. Current technology to support the knee diagnosis and treatment procedures are limited to use of manual goniometer, x-ray and magnetic resonance imaging (MRI). X-ray and MRI technologies are useful to have some insight on the knee problem, but they are not applicable for continuous monitoring. One of the key methods used by physiotherapist to access knee health condition is by measuring knee joint angle during gait and identify the angular range for the knee movement of the patient in the frontal plane

Classical angular tracking and intelligent anti-sway control for rotary crane system

This paper presents investigations into the development of hybrid control schemes for sway suppression and rotational angle tracking of a rotary crane system. A lab-scaled rotary crane is considered and the dynamic model of the system is derived using the Euler-lagrange formulation. To study the effectiveness of the controllers, initially a classical controller which is collocated proportional-derivative (PD) controller is developed for control of rotary motion. This is then extended to incorporate a non-collocated fuzzy logic controller for control of sway angle of the pendulum. Implementation results of the response of the rotary crane system with the controllers are presented in time and frequency domains. The performances of the control schemes are assessed in terms of level of sway reduction, rotational angle tracking capability and time response specifications. Finally, a comparative assessment of the control techniques is presented and discussed

A novel implementation of knee joint monitoring device using step index optical fibre and linear array photodiode sensor

Knee monitoring is one of the common injuries suffered by people who are active in extreme sports. Traditional ways to identify these problems are based on background study of the patient, physical examination, and sometimes with the use of x-rays and MRIs. The use of x-rays and MRIs for repetitive use is not preferably suggested by physicians due to the high cost and other associated side-effect related to exposure to radiation. Due to these factors, an alternative device based on optical fibre sensor is proposed in this study. The proposed knee monitoring sensor is based on the use on step index type plastic optical fibre and linear array photodiode sensor. Based on the mathematical estimation and initial sensor measurement, this sensor is able to perform full range of motion between 0 to 155 degrees. The accuracy and resolution of this sensor is 1.0 degree and 0.5 degree, respectively. The aim of this study is to determine the current performance of the device before further improvement could be proposed

Dynamic Modelling of a Double‐Pendulum Gantry Crane System Incorporating Payload

This paper presents dynamic modelling of a double-pendulum gantry crane system based on closed-form equations of motion. A dynamic model of the system incorporating payload is developed and the effects of payload on the response of the system are discussed. Extensive results that validate the theoretical derivation are presented in the time and frequency domains

Performance optimization of automotive air-conditioning system operating with al2o3-sio2/pag composite nanolubricants using taguchi method

The performance of an automotive air-conditioning (AAC) system is influenced by a variety of operating conditions. This can be addressed by employing optimization techniques that can suggest the appropriate parameters for the best results. In this study, the optimum operating conditions for a composite nanolubricants-fuelled AAC system were investigate using Taguchi's design of experiment approach and analysis of variance (ANOVA). The motor speed value, initial refrigerant charge, and composite nanolubricants composition ratio were chosen as operating parameters to investigate the AAC system performance, focusing on the coefficient of performance (COP) and compressor work. Orthogonal arrays (ORs) L25 (56) was selected to determine the optimum operating parameters of the AAC system. The optimum values for speed, refrigerant mass, and composition ratio were determined to be A4B1C5 (60:40, 900 rpm and 155 g), respectively. The motor speed was the significant factor influencing both COP and compressor performance by 78.13% and 89.29%. A confirmation test was conducted with the optimum levels of AAC system parameters to verify the efficiency of the Taguchi optimization method. The validation between the optimization results and the experimental results yielded a maximum error of 9.85%, indicating that the findings of this investigation were acceptable