Embryo injection is a significant technique in molecular biology and drug discovery for zebrafish, one of the most popular model organisms. Traditional zebrafish embryo injection is manually... Show More

Embryo injection is a significant technique in molecular biology and drug discovery for zebrafish, one of the most popular model organisms. Traditional zebrafish embryo injection is manually conducted under microscope, requiring challenging coordination of hand (to manipulate), eye (to watch) and even foot (to trigger the microinjector), and their respective precise control as well as being labor intensive. An automatic operating process for zebrafish embryo injection is proposed in this paper. Based on a micromanipulation robot system, the operating process integrates computer vision and micromanipulation robot control to realize batch embryo quantitative injection automatically. Successful rate of 93% and survival ratio of 89.5% at operating speed of 6-7 embryos/minute are obtained, verifying the feasibility and effectiveness of the process. Finally, the process is applied to inject a fluorescent material and investigate the toxicity of a dye, both receiving success.

This paper presents a sliding mode control scheme to improve the positioning performance of a 2-Degree-of-freedom (DOF) torsional MEMS micromirror with sidewall electrodes. The stability of... Show More

This paper presents a sliding mode control scheme to improve the positioning performance of a 2-Degree-of-freedom (DOF) torsional MEMS micromirror with sidewall electrodes. The stability of closed-loop system is proved by Lyapunov stability theorem under the existence of bounded parameter uncertainties and external disturbances. Furthermore, the performance of the closed-loop system is illustrated by experimental and simulation results which verify that the feasibility and effectiveness of the proposed scheme. The results demonstrated that the torsional MEMS micromirror with the proposed sliding mode controller has a good transient response and tracking performance.

Object-detection and classification is a key task in micro- and nanohandling. The microscopic imaging is often the only available sensing technique to detect information about the positions and... Show More

Object-detection and classification is a key task in micro- and nanohandling. The microscopic imaging is often the only available sensing technique to detect information about the positions and orientations of objects. FPGA-based image processing is superior to state of the art PC-based image processing in terms of achievable update rate, latency and jitter. A connected component labeling algorithm is presented and analyzed for its high speed object detection and classification feasibility. The features of connected components are discussed and analyzed for their feasibility with a single-pass connected component labeling approach, focused on principal component analysis-based features. It is shown that an FPGA implementation of the algorithm can be used for high-speed tool tracking as well as object classification inside optical microscopes. Furthermore, it is shown that an FPGA implementation of the algorithm can be used to detect and classify carbon-nanotubes (CNTs) during image acquisition in a scanning electron microscope, allowing fast object detection before the whole image is captured.

A new concept of Atomic Force Microscope (AFM) oscillating probes using electrostatic excitation and piezoresistive detection is presented. The probe is characterized by electrical methods in a... Show More

A new concept of Atomic Force Microscope (AFM) oscillating probes using electrostatic excitation and piezoresistive detection is presented. The probe is characterized by electrical methods in a vacuum chamber and by mechanical methods in air. The frequency-mixing measurement technique is developed to reduce the parasitic signal level. These probes resonant in the 1MHz range and the quality factor is measured about 53000 in vacuum and 3000 in air. The ring probe is mounted onto a commercial AFM set-up and the surface topography of PMMA sample (2 µm square) is obtained. The force resolution deduced from the measurements is about 10 pN/Hz0.5.

The goal of this paper is to improve the performance of the well known Q learning algorithm, the robust technique of Machine learning to facilitate path planning in an environment. Until this time... Show More

The goal of this paper is to improve the performance of the well known Q learning algorithm, the robust technique of Machine learning to facilitate path planning in an environment. Until this time the Q learning algorithms like Classical Q learning(CQL)algorithm and Improved Q learning (IQL) algorithm deal with an environment without obstacles, while in a real environment an agent has to face obstacles very frequently. Hence this paper considers an environment with number of obstacles and has coined a new parameter, called ‘immediate penalty’ due to collision with an obstacle. Further the proposed technique has replaced the scalar ‘immediate reward’ function by ‘effective immediate reward’ function which consists of two fuzzy parameters named as, ‘immediate reward’ and ‘immediate penalty’. The fuzzification of these two important parameters not only improves the learning technique, it also strikes a balance between exploration and exploitation, the most challenging problem of Reinforcement Learning. The proposed algorithm stores the Q value for the best possible action at a state; as well it saves significant path planning time by suggesting the best action to adopt at each state to move to the next state. Eventually, the agent becomes more intelligent as it can smartly plan a collision free path avoiding obstacles from distance. The validation of the algorithm is studied through computer simulation in a maze like environment and also on KheperaII platform in real time. An analysis reveals that the Q Table, obtained by the proposed Advanced Q learning (AQL) algorithm, when used for path-planning application of mobile robots outperforms the classical and improved Q-learning.

The performances of three attitude determination algorithms are compared in this paper. The three methods are the Complementary Filter, a Quaternion-based Kalman Filter and a Quaternion-based... Show More

The performances of three attitude determination algorithms are compared in this paper. The three methods are the Complementary Filter, a Quaternion-based Kalman Filter and a Quaternion-based Gradient Descent Algorithm. An analysis of their performance based on an experimental investigation was undertaken. This paper shows that the Complementary Filter requires the least computational power; Quaternion-based Kalman Filter has the best noise filtering ability; and the Quaternion-based Gradient Descent Algorithm produced estimates with the highest accuracy. As many attitude determination methodologies make use of the quaternion rotation representation, the attitude quaternion to Euler angle singularity property has been investigated. Experiments conducted show that when Y-rotation approach the singularity position (±90°), the X-rotation drifts away from the reference input. This paper proposes the use of an imaginary set of sensor measurements to replace the original sensor measurements as the Y-rotation approaches the singularity. The proposed methodology for overcoming the conversion singularity has been experimentally verified.

Optimal distribution of forces for manipulation by a robot hand, is a hard computational issue, specifically once a whole hand grasp is needed. It becomes a complicated issue, once a robotic hand is... Show More

Optimal distribution of forces for manipulation by a robot hand, is a hard computational issue, specifically once a whole hand grasp is needed. It becomes a complicated issue, once a robotic hand is equipped with human like deformable sensory touching materials. For computing optimal set of manipulation forces, grip transform and inverse hand Jacobian play major roles for such purposes. This manuscript is discussing a Neurofuzzy learning technique for learning optimal force distribution by a dextrous hand. For learning purposes, optimal set of forces patterns were gathered in advanced using optimization formulation technique. After that, to let a Neurofuzzy system to learn the nonlinear kinematics-dynamics relations needed for force distribution. This is done by considering the computational requirements for the inverse hand Jacobian, in addition to the interaction between hand fingers and the object. Training patterns clustering, and generation of the fuzzy initial memberships, and updated shape of memberships, are considered as vital information to build upon for more reasoning of fuzzy interrelation. The technique is novel in a sense, that the adopted Neurofuzzy architecture was transparent in terms of revealing the learned hand optimal forces if then rules.

This paper presents the mechanical design and experimental characterization of a 2-DOF serial flexure-based micropositioning table. The cascade mechanical structure is proposed to implement planar... Show More

This paper presents the mechanical design and experimental characterization of a 2-DOF serial flexure-based micropositioning table. The cascade mechanical structure is proposed to implement planar motions of the moving platform. In order to increase the stroke of the moving platform, a lever mechanism is designed to amplify the displacement of the piezoelectric actuator. The finite element method is utilized to analyze the mechanical and thermal characteristics of the proposed 2-DOF micropositioning table. The WEDM (Wire Electro-Discharge Machining) technique is used to manufacture the prototype of the micropositioning table. A number of experimental tests have been conducted to investigate the characteristics of the developed system.

This paper presents a new robust adaptive unscented particle filtering algorithm by adopting the concept of robust adaptive filtering to the unscented particle filter. In order to prevent particles... Show More

This paper presents a new robust adaptive unscented particle filtering algorithm by adopting the concept of robust adaptive filtering to the unscented particle filter. In order to prevent particles from degeneracy, this algorithm adaptively determines the equivalent weight function according to robust estimation and adaptively adjusts the adaptive factor constructed from predicted residuals to resist the disturbances of singular observations and the kinematic model noise. It also uses the unscented transformation to improve the accuracy of particle filtering, thus providing the reliable state estimation for improving the performance of robust adaptive filtering. Experiments and comparison analysis demonstrate that the proposed filtering algorithm can effectively resist disturbances due to system state noise and observation noise, leading to the improved filtering accuracy.

Most of the micro/nano manipulation mechanisms and systems are commonly based on flexure-based monolithic structures, and are generally driven by piezoelectric actuators. In the presented work... Show More

Most of the micro/nano manipulation mechanisms and systems are commonly based on flexure-based monolithic structures, and are generally driven by piezoelectric actuators. In the presented work, experimental system identification, 1-DOF trajectory tracking with feed-forward control, and hysteresis compensation are investigated. An experimental research facility with laser interferometry-based sensing and measurement technique is established. System identification experiments were performed on a 2-DOF flexure-based mechanism to investigate its dynamics. The system identification procedure, experimental design, data acquisition, analysis and validation of the identified system are presented in details. A linear sine swept signal is applied to the system as an input and the corresponding response of the system is measured with laser interferometry-based sensing and measurement technique. The experimental results are used to evaluate the transfer function and the first natural frequency of the system in the X and Y axes. Experimental validation data is used to verify the accuracy of the identified model. Further, a feed-forward controller is established to track a 1-DOF smooth multiple-frequency trajectory. For hysteresis compensation, inverse PI (Prandtl–Ishlinskii) model is derived from classical PI model. The parameters of the inverse PI model is estimated and validated with the experimental data. Finally, inverse PI model is directly adopted as a feed-forward controller for hysteresis compensation of piezoelectric actuators.

Utility theory and the principle of maximising the expected utility have, within the multi-agent community, had a great influence on multi-agent based decision. Even though this principle is often... Show More

Utility theory and the principle of maximising the expected utility have, within the multi-agent community, had a great influence on multi-agent based decision. Even though this principle is often useful when evaluating a decision situation it is virtually impossible, except in very artificial situations, to use the more basic decision rules with its unrealistically strong requirements for the input data, and other candidate methods must be considered instead. This article provides an overview and brings attention to some of the possibilities to utilize more elaborated decision methods, while still keeping the computational issues at a tractable level.

Game Theory has recently drawn attention in new fields which go from algorithmic mechanism design to cybernetics. However, a fundamental problem to solve for effectively applying Game Theory in real... Show More

Game Theory has recently drawn attention in new fields which go from algorithmic mechanism design to cybernetics. However, a fundamental problem to solve for effectively applying Game Theory in real word applications is the definition of well-founded solution concepts of a game and the design of efficient algorithms for their computation. A widely accepted solution concept for games in which any cooperation among the players must be self-enforcing (non-cooperative games) is represented by the Nash equilibrium. However, even in the two players case, the best algorithm known for computing Nash equilibria has an exponential worst-case running time; furthermore, if the computation of equilibria with simple additional properties is required, the problem becomes NP-hard. The paper aims to provide a solution for efficiently computing the Nash equilibria of a game as the result of the evolution of a system composed by interacting agents playing the game.

The following chapter describes two systems, which both are perfect examples for ambient intelligence: sensor electronics, which is invisibly integrated into the floor. The first system comprises... Show More

The following chapter describes two systems, which both are perfect examples for ambient intelligence: sensor electronics, which is invisibly integrated into the floor. The first system comprises active sensors with high spatial resolution. It is able to detect people walking across the floor and recognizes peoples' location and movement behaviour. While the main application domains are Ambient Assisted Living (AAL), health care, security systems and home automation, several robotics applications are possible and have been investigated already. The second system serves for localizing moving objects such as robots, wheelchairs or hospital beds by means of passive RFID tags in the floor and an active RFID reader attached to the moving object. In the following, we describe the technical details of the two systems and robotics applications, which have already been realized or are under development.

Pipe inspection is one of the areas that have attracted high research interest for robot applications especially in oil and chemical industry and civil engineering. Robot body rolling while it... Show More

Pipe inspection is one of the areas that have attracted high research interest for robot applications especially in oil and chemical industry and civil engineering. Robot body rolling while it travels within a pipe has been a problem for accurately collecting inspection data. Under certain circumstances where vision systems have to be employed, robot body rolling may cause vision inspection data to have little value as it is difficult to know where exactly the camera was looking at. This paper proposes an anti-rolling mechanism to hold consistent camera orientation. By changing the position angle of the robot legs, the mechanism is able to adjust the resistance to rolling within a pipe, therefore preventing robot rolling happening. The design makes use of the friction force caused by the gravity force of the robot to prevent the robot body rolling. The design analysis quantifies the effect of pipe radius, robot weight, payload, and payload offset distance in robot rolling. A test model was built based on the design concept. The experimental results obtained from the test model match the predication of the computational analysis. A real time vision system has been developed using FPGA and the algorithm of the structured laser light stripe configuration in the context of pipe inspection. The real-time hardware implementation of the algorithms on the robot itself removes the need to transmit raw video data back to an operator.

This work deals with modelling and experimenting of a compliant serial-parallel robot. Using Pseudo-Rigid-Body Modelling (PRBM) of elastic structures, a kinematics and stiffness model of a... Show More

This work deals with modelling and experimenting of a compliant serial-parallel robot. Using Pseudo-Rigid-Body Modelling (PRBM) of elastic structures, a kinematics and stiffness model of a serial-parallel structure has been built. Several approaches for pre-tensioning of a parallel structure with elastic joints were developed in order to eliminate backlashes and improve the performance of its actuators. In this work a robot is designed to inject biological cells with size in the range of 10-30µm. The approaches used for pre-tensioning of the robot have been analysed and subjected to numerical evaluation. Assessing the mechanical parameters of the tensed manipulator has been performed using the following methods: PRBM and Finite Element Analysis (FEA). An experimental set-up for testing a robot prototype has been developed, using an optical system and correlation technique for digital image processing. The experimental results obtained are compared to data received from the numerical experiment.

Robotics is a field which includes multiple disciplines such as environment mapping, localization, path planning, path execution, area exploration etc. Path planning is the elementary requirement... Show More

Robotics is a field which includes multiple disciplines such as environment mapping, localization, path planning, path execution, area exploration etc. Path planning is the elementary requirement for all the above mentioned diversified fields. This paper presents a new method for motion planning of mobile robots which carry forward the best features of Focused Wave Front and other wave front based path planners, at the same time optimizes the algorithm in terms of path length, energy consumption and memory requirements. This research introduces a method of choosing every next step in grid based environment and also proposes a backtracking procedure to minimize turns by means of identifying landmark points in the path. Further, the authors have enhanced the functionality of Focused Wave Front algorithm by applying it in uncertain dynamic environment. The proposed method is a combination of global and local path planning as well as online and offline navigation process. A new method based on bidirectional wave propagation along the walls of obstacle and wall following behavior is being proposed for avoiding uncertain static obstacles. Considering the criticalness of moving obstacles a colored safety zone is assumed to have around them and the robot is equipped with color sensitivity. Based on the particular color (red, green, yellow) that has sensed the robot will make intelligent decisions to avoid them. The simulation result reflects how the proposed method has efficiently and safely navigates a robot towards its destination by avoiding all known and unknown obstacles. Finally the algorithms are extended for multi-robot environment.

SRS is a European research project for building robust personal assistant robots using ROS (Robotic Operating System) and Care-O-bot (COB) 3 as the demonstration platform. A semi-autonomous... Show More

SRS is a European research project for building robust personal assistant robots using ROS (Robotic Operating System) and Care-O-bot (COB) 3 as the demonstration platform. A semi-autonomous framework has been developed in the project. It consists of an autonomous control structure and user interfaces that support the semi-autonomous operation. The control structure is divided into two parts. First, it has an automatic task planner, which initialises actions on the symbolic level. The planner produces proactive robotic behaviours based on updated semantic knowledge. Second, it has an action executive for coordination actions at the level of sensing and actuation. The executive produces reactive behaviours in well-defined domains. The two parts are integrated by fuzzy logic based symbolic grounding. As a whole, they represent the framework for autonomous control. Based on the framework, SRS user interfaces are integrated on top of COB's existing capabilities to enable robust fetch and carry in unstructured environments.

As micro- and nano-devices become smaller, the ability to manipulate them with highly accurate control is increasingly important as well. The design of a micro-joint is important for highly accurate... Show More

As micro- and nano-devices become smaller, the ability to manipulate them with highly accurate control is increasingly important as well. The design of a micro-joint is important for highly accurate movement. In this paper, the authors discuss a new micro translational joint based on an elastic-design concept for large, precise translational motion. Using the elastic deformation of spiral structures, the new translational joint is able to accomplish precise movements over long distances. Because the proposed translational joint is integrated, there is no gap and it is thus able to move without friction. Through finite element method (FEM) simulation, the proposed translational joint was estimated to have large, but still precise, translational motion. An experiment was conducted on the optical tweezer with the result showings that the proposed joint is also capable of large, precise translational movement at the micro scale. Therefore, it is expected that there will be many applications for which the proposed translational joint can be used for the precise manipulation of micro and nano-scale devices.

This paper presents a survey of the contemporary assistive chairs and on-chair sensing approaches of capturing sit-to-stand (STS) movement. Sitting in a chair and standing up from a seated position... Show More

This paper presents a survey of the contemporary assistive chairs and on-chair sensing approaches of capturing sit-to-stand (STS) movement. Sitting in a chair and standing up from a seated position are activities of daily living (ADLs) performed by humans. However, older people often encounter difficulties with these activities. These difficulties may cause substantial decreasing of the elderly mobility, leading to inactive participation in social activities and increasing the risk of chronic diseases that may cause premature death. Therefore, assisting older people to overcome these difficulties has significance for their independent living. At present, the assistive devices can be allocated in terms of market available ones and experimental prototypes, both of which are discussed here. Afterwards, the authors cast more light on integrated sensing techniques that are currently used with experimental prototypes and create a taxonomy of sensing techniques. Following from this survey, a chair capable of delivering assistance-as-needed is proposed.