595 research outputs found
[[alternative]]The research of knowledge management for high-tech industry-A case of Microlife
No full text[[abstract]]The main purpose for this study is to probe into the knowledge management in high-tech industry. It discusses not only the opinions of domestic and overseas scholars and some situations about overseas businesses by record, but also chooses some special companies to do deeper visit to know real situations and problems when knowledge management is carried out. Finally, we give some substantial and specific suggestions to those companies that have problems and the one which wants to carry out knowledge management.
The conclusion is as following:
1. Discussion on Knowledge-based Theory
From records we know that knowledge is divided into two categories - explicit and tacit knowledge. Only when combining the two can we build a complete knowledge system and basis.
2. The Knowledge Management of High-tech Industry
We find that the purposes and ways we practice knowledge management in domestic businesses are different to those overseas. For example, the purpose of domestic database systems and intranet is merely to transmit messages or to communicate. But overseas database systems not only have the functions of documentization and digitalization, but also can analyze knowledge system.
3. The Problem of Carrying Out Knowledge Management in High-Technology Business
There are many uncertain factors when a company establishes knowledge base or delivers experiences. Therefore, in this study, we suggest to carry out by dividing into several stages or implementing in parts. Dividing into several stages is to set up the connective and technical standards among branch systems and then establish each subsystem according to the situation in the business; to carry out in parts means to build a message center to consolidate and integrate all departments.
Assessment of functional benefits of wearable robotic assistive technologies
No full textStroke is one of the most common causes of upper-limb disability and loss of the ability to perform everyday tasks. Stroke rehabilitation is an important part of recovery after stroke to help stroke patients restore their mobility. In Singapore, there are two general pathways for post-stroke care: outpatient rehabilitation and inpatient rehabilitation centres. However, these methods are not as feasible as there is a shortage of trained therapists and stroke patients often have difficulty traveling back and forth to the rehabilitation centre due to their immobility. To overcome these limiting factors, an in-home robotic rehabilitation program can be included as one of the pathways for post-stroke care in Singapore where post-stroke patients participate in therapy in the comfort of their own house without the need for a therapist. Rehabilitation robots can be incorporated with sensors to provide input to the patient in the comfort of their own home. Therefore, this project aims to provide stroke patients with home-based monitoring and assessment without the need for a therapist. To achieve this objective, this project will be evaluating the movement accuracy of the assistive robot arm extender in helping post-stroke patients with their rehabilitation. Inertia Measurement Unit (IMU) sensors are used to estimate the range of motion and upper limb joint angles using direct kinematics and inverse kinematics. The range of motion and upper limb joint angles obtained will then be validated against motion capture which is known as the gold standard for dynamic measurement.Bachelor of Engineering (Mechanical Engineering
Development of haptic feedback joystick on powered wheelchair for obstacle avoidance
No full textHaptic joystick is an interface incorporating force feedback to enhance the task performance and improve reaction time of wheelchair drivers. It is able to help the wheelchair drivers with visual impairment to compensate for the lack of visual information and raise their situational awareness by introducing haptic feedback. Most of the joystick design are inefficient in terms of energy transmission and focus on active force feedback. This project presents a development of a 2 degree of freedom (DOF) haptic joystick with direct-drive mechanism for efficient energy transmission. The force feedback is powered by 2 high torque direct drive brushless DC motor (BLDC) connected in gimbal structure for decoupled mechanism and stiffen control. The project also focuses on passive force feedback mechanism with the BLDC being programmed as spring and damper system using proportional-derivative (PD) controller. The joystick stiffness of the virtual spring would increase based on level of dangerousness computed by obstacle avoidance algorithms. As user move closer to obstacle, a larger stiffness would be produced. Thus, preventing user from moving into that particular direction. Lastly, three obstacle avoidance algorithms, namely Dynamic Window Approach(DWA), Potential Field Algorithm(PFA) and Obstacle Dependent Gaussian Potential Field Algorithm(ODGPFA), are integrated into the haptic feedback algorithms. An experiment was carried out where participants are required to drive a series of obstacle course to evaluate both the effectiveness of the haptic feedback system and the compatibility of the three different obstacle avoidance algorithms. Results shows that haptic joystick helps to reduce number of collisions. However, it increases the time taken to completion due to more difficult to accelerate caused by stiffen haptic joystick. According to user reviews, it shows that ODG-PFA has the best compatibility with the feedback mechanism due to its advancement in identifying obstacle and steady force increment.Bachelor of Engineering (Mechanical Engineering
The influences of basic physical properties of clayey silt and silty sand on its laboratory electrical resistivity value in loose and dense conditions
No full textNon-destructive test which refers to electrical resistivity method is recently popular in engineering, environmental, archaeological and mining studies. Based on the previous studies, the results on electrical resistivity interpretation were often debated due to lack of clarification and evidences in quantitative perspective. Traditionally, most of the previous result interpretations were depending on qualitative point of view which is risky to produce unreliable outcomes. In order to minimise those problems, this study has performed a laboratory experiment on soil box electrical resistivity test which was supported by an additional basic physical properties of soil test like particle size distribution test (d), moisture content test (w), density test (ρbulk) and Atterberg limit test (LL, PL and PI). The test was performed to establish a series of electrical resistivity value (ERV) with different quantity of water content for clayey silt and silty sand in loose and dense condition. Apparently, the soil resistivity value was different under loose (L) and dense (C) conditions with moisture content and density variations (silty SAND = ERVLoose: 600 - 7300 Ωm & ERVDense: 490 - 7900 Ωm while Clayey SILT = ERVLoose: 13 - 7700 Ωm & ERVDense: 14 - 8400 Ωm) due to several factors. Moreover, correlation of moisture content (w) and density (ρbulk) due to the ERV was established as follows; Silty SAND: w(L) = 638.8ρ-0.418, w(D) = 1397.1ρ-0.574, ρBulk(L) = 2.6188e-6E-05ρ, ρBulk(D) = 4.099ρ-0.07 while Clayey SILT: w(L) = 109.98ρ-0.268, w(D) = 121.88ρ-0.363, ρBulk(L) = -0.111ln(ρ) + 1.7605, ρBulk(D) = 2.5991ρ-0.037 with determination coefficients, R2 that varied from 0.5643 – 0.8927. This study was successfully demonstrated that the consistency of ERV was greatly influenced by the variation of soil basic physical properties (d, w, ρBulk, LL, PL and PI). Finally, the reliability of the ERV result interpretation can be enhanced due to its ability to produce a meaningful outcome based on supported data from basic geotechnical properties
Development of eye gaze system for object selection in cluttered environment
No full textIn recent years, eye gaze or eye tracking is gaining a lot of traction, particularly in gaze-based human robot interaction (HRI). The information obtained from eye tracking can be used for a variety of purposes including but not limited to object grasping, wheelchair navigation and accessing computers or communication aids. There is a need to accurately decipher the eye gaze information collected. However, modelling eye gaze information as a fixation or fixing it onto one point is not sufficient as natural eye gaze fluctuates around an area. This issue is further exacerbated in a cluttered environment, as the user’s eye gaze is scattered across many objects. This project aims to explore a feasible solution to ensure the user is able to correctly convey their intentions for object selection in a cluttered environment while maintaining user comfort. This project uses an eye gaze system, Pupil Core from Pupil Labs and is implemented in a ROS environment. This project also utilizes a Mask R-CNN, Detectron2 for object detection. This project also makes use of the Wasserstein metric as an evaluator to compare the probability distribution between the objects’ saliency map and the user’s eye gaze distribution to predict the user’s intention for object selection.Bachelor of Engineering (Mechanical Engineering
Development of an optical micro-motion sensing system
No full textPhysiologic hand Tremor is a common trait among humans although it varies in amplitude and frequency from individuals to individuals. It is generally unnoticeable as its amplitude is small. The amplitude of hand tremor can worsen due to anxiety, fatigue or use of stimulants like caffeine. However, it is a big factor limiting the effectiveness of microsurgery performed by microsurgeons. Microsurgery is usually performed under the microscope and gave the surgeons no force feedback. A steady hand that moves with high precision is desired for microsurgery.
Instruments to compensate for hand tremor have been developed to reduce the tremor and improve the precision of microsurgeons. To effectively compensate for the tremor, a highly accurate tremor measuring device is needed. Thus, an optical based Micro Motion Sensing System (M2S2) has been invented by a graduate student. However, over the years, its performance has deteriorated.
This study has been conducted to find out ways to improve the performance of M2S2. In addition, M2S2 is only able to measure 3 dimensional position data. The study also works on devising a new system to capture in total 6 degrees of freedom motion data (3 dimensional position data + Pitch, Yaw & Rotation). The two objectives of the study have been met within the scopes specified.Bachelor of Engineering (Mechanical Engineering
Mechatronic device for active rehabilitation of upper limbs
No full textPatients may experience difficulties in moving their joints after extensive surgery.
As a result, tissue around the joint will stiffen and scar tissue will form. Therefore
lengthy physical therapy would be necessary for rehabilitation. Continuous Passive
Motion (CPM) is a therapy method designed to aid in the recovery of joints after
surgery. CPM is achieved using motorised device to move the joint constantly. CPM
machine will move the patient‟s forearm about the elbow joint through a defined
range of motion for an extended period of time in order to help the patient regain his
range of motion. However, this method of compensating for lack of ability of the
patient to move his limbs has it flaws. The current technologies of CPM machines do
not require any effort from the user to participate actively during the rehabilitation
exercise. As time passes, the patient may lack motivation in the rehabilitation which
will hinder further recovery.
Therefore Electromyography (EMG) is introduced in this project. EMG is a
method to evaluate and record the electrical activity produced by muscles. The activation
of the exerciser would be based on the EMG signals of the user‟s muscles.
When the user flexes or extends his arm, EMG signals are acquired by an EMG system.
Once the signals detected exceed his threshold, which is pre-set based on his
Maximum Voluntary Contractions (MVC), a program built using LabVIEW will
trigger a motor and activate an exerciser to assist him with the flexion or extension
motion. This type of rehabilitation is suitable to be used by the patients at any point
of time. It helps to motivate the patients to be independent and involve the patient
more in the rehabilitation.
The author designed and implemented a compact, portable, and modular
mechatronic device that can be used for wrist and elbow rehabilitation. A single actuator
is used, and various types of wrist and elbow exercises can also be executed by
adjusting a knob on the device. Besides that, the author also tried out the device on
healthy patients. From the experiments, the author discovered that different type of
person will give different initial EMG values and Maximum Voluntary Contraction
(MVC) values. Therefore, the therapist needs to set different the maximum threshold
value for different patients.Bachelor of Engineering (Mechanical Engineering
Design and control of piezoelectric-driven handheld manipulator for tremor compensation in microsurgery
No full textThe problem of correcting imprecision due to physiological hand tremor while performing micromanipulation tasks such as microsurgery has received considerable attention. This results in the development of a hand-held instrument, Micron, that senses its own motion using an inertial measurement unit; distinguishes intended and undesired motion, and actively attenuates the undesired motion by an opposite but equal deflection of the tip through a piezoelectric-driven manipulator. This dissertation emphasizes an improved version of the aforementioned instrument with regards to the design and control of the piezoelectric-driven mechanism.
The hysteretic behavior of piezoelectric actuators makes control challenging. Hence,
Prandtl-Ishlinskii (PI) hysteresis model is used to model this hysteretic effect. However, there is a limitation in the PI model. The inverse does not exist when the
slope of the hysteretic curve is not positive definite. The author proposes over-
coming this problem by mapping the hysteresis through a transformation onto a
singularity-free domain, where the inversion can be obtained. The proposed solution brings along a number advantages to the instrument: 1) a stable controller as the limitation of the inverse model is removed; 2) better accuracy as smaller threshold values can be used; and 3) accelerometers will no longer pick up impacts caused by the jerks at the turning point due to the singularity problem. This solution is a general method and can be extended to model any hysteretic materials or systems.
The hysteretic behavior is dependent on the individual actuator and also environmental conditions like temperature. Hence, the actuator has to be modeled regularly. To overcome this, the author proposes closing the feedback loop to obtain an adaptive rate-dependent feedforward controller for piezoelectric actuators. The tracking performance of the adaptive controller is performed on a piezoelectric actuator and found to produce a smaller tracking error. In addition, since it is adaptive, experiments are no longer needed to be conducted to obtain the actuator’s model and precious time is saved.
This dissertation also presents a new piezoelectric-driven 3-DOF flexure-based par-
allel mechanism. To reduce the cost and also to allow complexity in the design to reduce the size, a rapid prototyping machine (Objet) is used to build the mechanism portion as a single piece.DOCTOR OF PHILOSOPHY (MAE
Microinjection and cell membrane strain control using vision guided robotic cell micromanipulation system
No full textThis dissertation presents methodologies to measure, model and control the cell membrane strain in real-time by using a vision guided robotic cell micromanipulation system. The system includes a motion unit to control the position of the micropipette in six degrees of freedom, a vision unit to process the image information from the camera and a holding unit to immobilize the cell for strain control. An indirect depth estimation method is proposed to place the target cell and the tip of the micropipette on the same focal plane without taking any risk of damaging the fragile tip of the micropipette, which minimizes the position error between the micropipette and the target cell. The cell membrane deformation is estimated by the peripheral and the local deformation and a real-time machine vision algorithm is proposed to track the changes of cell membrane deformation. The proposed method speeds up the sampling rate of the cell strain control system to 10 Hz and no manual adjustment of parameters is required throughout the experiment. A real-time cell strain control system is proposed by employing the knowledge of the strain model through the feedforward input and accounting for errors using the feedback controller. The experimental results show that the maximum error between the desired and the actual cell membrane strain is within 3%.DOCTOR OF PHILOSOPHY (MAE
Design of a motion capture trial for upper limb movement analysis
No full textStroke rehabilitation is a major area of research in today’s world, in particular motion tracking. In order to monitor a patient’s progress in rehabilitation, an efficient motion tracking system needs to be in place in a hospital, taking into mind, space limitations. This thesis aims to provide an optimal system to track the upper limb movement of normal subjects and address any issues that may arise due to motion tracking, such as occlusion of markers, to provide a stable and reliable system for future trials to be conducted on stroke patients in hospitals. A total of 18 healthy subjects were asked to perform 9 activities of daily living and their movements were tracked by the Qualysis motion capture system. Issues such as occlusion which is bound to occur in any motion tracking system, were minimized by the creation of rigid bodies. The limitations and merits of the system are highlighted, with potential suggestions and future applications of this system.Master of Science (Biomedical Engineering
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