Recently, robotics has played a more and more important role in scientific research and engineering applications. Being an essential topic, the problem of redundancy resolution (or mostly say, the problem of inverse kinematics, which is related to the kinematic control of some redundant robot manipulator) has attracted the extensive attention of many researchers. The general description of such a problem is that, given the desired Cartesian path r d ( t ) ∈ ℝ m of the end-effector versus time t ∈ [ t 0 , t f ] ⊆ [0, ∞), the corresponding trajectories of joint-variable vector θ ( t ) ∈ ℝ n need to be obtained online (or offline and in advance).

A redundant manipulator is defined when more degrees of freedom (DOF) are available than the minimum number of DOF required to execute a given end-effector primary task. Our human arm, elephant trunk, and snake are also such redundant systems. Compared to non-redundant manipulators, the redundant manipulator naturally has wider operational space and extra degrees to meet more functional constraints, such as the online avoidance of joint physical limits and environmental obstacles. One of the most fundamental issues in operating the redundant manipulators is the redundancy-resolution problem. That is, given the Cartesian velocity/acceleration trajectories of the end-effector, we are required to generate the corresponding joint velocity, acceleration, and/or torque trajectories in real time.

Kinematic redundancy can be obtained when a robot manipulator possesses more DOF than the minimum number required to execute a given end-effector task. If a robot manipulator is redundant, the inverse-kinematics problem may admit infinite solutions. How to obtain the required optimal solution, that is, the redundancy resolution problem, is an appealing and significant topic in robotics areas. In the past, many redundancy resolution schemes have been presented, and they can be divided into two main categories; that is, globally optimal control of redundancy and local/instantaneously optimal control of redundancy. The globally optimal concept and method were originally suggested by Whitney, and the early effective global schemes were presented by Uchiyama et al . and Nakamura et al . The global optimal schemes can generate the global optimal solutions, but they require a large amount of computation and are not suitable for real-time kinematic resolution. The detailed discussion can be referred to [143]. Thus, the local/instantaneously optimal control schemes are widely investigated and used in robotics areas. The classic local optimal solution is pseudoinverse-type formulation, which is investigated in Chapter 1; that is, one minimum-norm particular solution plus a homogeneous solution. Based on such a pseudoinverse-type solution, many optimization performance criteria have been exploited in terms of manipulator configurations and interaction with the environment, such as joint-limits avoidance, singularity avoidance, manipulability enhancement, and obstacle avoidance. Recent research shows that the solutions to redundancy resolution problems can be enhanced by using optimization techniques based on quadratic program (QP) methods. Compared with the classic pseudoinverse-based solutions, such QP-based methods do not need to compute the inverse of the Jacobian matrix, and are readily to deal with the inequality and/or bound constraints. Thus, new interests in QP-based methods have been generated. In [90], considering the physical limits, Cheng et al . presented a compact QP method to resolve the constrained kinematic redundancy problem. As a specific example in [90], a repetitive motion planning (RMP) scheme was presented to illustrate the effectiveness of the compact QP method. Note that such an RMP scheme is based on Euclidean norm (or two-norm), and used to remedy the non-repetitive problem of the closed end-effector path (which is different from the path tracked in this chapter). The two-norm was widely used because of its analytical tractability, but minimizing the two-norm solution was not an ideal choice. Thus, some researchers began to investigate the optimization schemes based on the infinity norm and minimizing the infinity norm implied the determination of a minimum-effort solution as opposed to the minimum-energy criterion associated with the Euclidean norm. The torque-level and acceleration-level optimization schemes have also been investigated. It is worth pointing out that various criteria are exploited to optimize different objectives according to the requirements in general.

A manipulator is said to be redundant when more DOF are available than the minimum number required to perform a specific end-effector primary task. For redundant manipulators, as discussed in previous chapters, the inverse kinematic resolution is a fundamental issue in operating the robot systems. The general description of this problem is that, given the desired Cartesian path r d ( t ) ∈ ℝ m for the manipulator’s end-effector to track, how can we generate the corresponding joint trajectory θ ( t ) ∈ ℝ n in real time t ? Note that n > m and, thus, there exist multiple or an infinite number of feasible solutions to the inverse-kinematic problem. In this sense, the redundancy of joint motion, together with kinematic and dynamic nonlinearities, complicate the manipulator control problem significantly.

Studies on and applications of a redundant robot manipulator are the topical research issues in the robotic community. In particular, the inverse-kinematics problem, which finds the joint motion for a given manipulator’s end-effector task is one of the important and challenging issues in operating the redundant manipulators. Note that there are an infinite number of joint configurations of a manipulator with respect to a specific task, due to the redundancy; and redundancy resolution is to make a suitable selection from the configurations. This kind of selection is usually used to accomplish some secondary tasks for robot manipulators or generate an optimal solution to achieve some performance criteria, besides finishing the main end-effector path-tracking task. The redundancy-resolution problem can be readily solved by optimization techniques, especially QP. Note that the quadratic program (QP) can be converted to a linear variational inequality (LVI), and the resultant LVI is equivalent to a piecewise-linear equation (PLE) that can be solved by many algorithms and techniques efficiently, such as numerical algorithm E47 and numerical algorithm 94LVI presented in previous chapters as well as recurrent neural networks.

The issue of optimal motion control in robotics is becoming a more and more appealing topic as robots are widely applied in scientific research, military and civilian areas, of which the operating environment is much more complicated than that in the past. Redundant manipulators can achieve subtasks such as obstacle avoidance, repetitive motion planning, joint limits, and singularity avoidance, or optimization of various performance criteria, since they have more degrees of freedom (DOF) than required to perform a given end-effector primary task. A fundamental issue in controlling such redundant manipulators is to design suitable redundancy-resolution approaches. The conventional solution to such a redundancy-resolution problem is the pseudoinverse-based formulation.

Fundamental understanding and elucidation of hydrogen assisted degradation and trapping mechanisms is dependent on sufficient imaging techniques for respective hydrogen interactions, in particular with multi-phase metallic microstructures. The present work shows the progress in elucidating the deuterium behavior in austenitic-ferritic duplex stainless steels under the consideration that deuterium behaves in many ways similarly to hydrogen. A novel combination of deuterium permeation and in-situ Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) imaging technique is compared with post charging ToF-SIMS imaging experiments. As a step beyond state-of-the-art, integration of chemo-metric and high resolution structural characterization techniques with computational multivariate data analysis (MVA) and data fusion is presented.

Medical ultrasound has been one of the most widely adopted and rapidly developing diagnosis and therapy tools today because of its non-destructive and non-ion radiative nature. Ultrasound transducers, as key components in medical ultrasound systems, have been developed for a variety of ultrasound 2D and 3D imaging with sub-millimeter to mm spatial resolution and Doppler blood flow information. Medical ultrasound imaging stems from the sonar technology, which was first developed in World War I for detecting submarines using acoustic waves with frequencies ranging between >20 kHz and 1 MHz. For a sonar transducer, a piece of piezoelectric material was used to produce and detect the acoustic pulses. The concept of sonar was later applied to image the human tissues by increasing the ultrasound frequencies above 1 MHz. Medical imaging with ultrasound was first demonstrated to be a useful clinical tool in the early 1950s by Wild and Reid, who reported the first two-dimensional imaging of soft tissues. With the first medical ultrasound system, a transducer was scanned mechanically across the body to form a two-dimensional (2-D) image slowly. Later in 1970, the development of linear arrays and electronic beamforming made real-time 2D imaging possible. The development of digital electronic beamforming in the 1980’s resulted in improved image quality and flexibility in scanning. Ultrasound is now applied in a broad range of topics of biology and medicine, and accounts for about one-third of all diagnostic imaging procedures.

Antenna array configuration plays an important role in HMI measurement system. This chapter demonstrates optimization of various antenna array configurations to generate a high-resolution image of dielectric objects by using the proposed technique. Three configurations include spiral, random and regularly spaced array are presented in this chapter, both simulation and experimental results are obtained and compared to fully demonstrate the effectiveness of antenna arrays to the HMI technique.

Non-invasive ultrasonic measurement of mechanical properties is very useful for diagnosis of biological tissues. For example, pathological change of the arterial wall due to atherosclerosis leads to a significant change in its mechanical properties [1, 2]. Most conventional methods for noninvasive measurement of elasticity are based on measurement of the pulse wave velocity (PWV) [3–6] or the change in diameter [7–10]. Although these methods are useful in terms of their ability to assess the vascular elasticity noninvasively, the spatial resolution in elasticity measurement is limited to the propagating distance of the pulse wave or the entire circumference.

A fully autonomous procedure to generate the Meshless point distribution in regular and irregular geometries may be devised with the use of Quadtree (Octree in 3D). A Quadtree is a tree data structure whose construction is based on the recursive decomposition of the Cartesian plane. Specifically, a region-based Quadtree is defined by the recursive partitioning of the Cartesian plane into four equally-sized quadrants which lie parallel to the coordinate axis. This recursion can be repeated until a model resolution criterion is achieved.

Magnetic precision stage is easy to realize micromotion with high resolution because a contact-free magnetic levitation technique is used between the moving plate and the driving part. The main parameters of drive circuit of a precision stage have been discussed. The power amplifier is designed based on L6234, the experimental results express that the drive method satisfied the demand of this stage's movement.

Cloud theory is a new theory handling uncertainty based on the uncertain transition between quality and quantity. The theory includes cloud model, virtual cloud, cloud operation, cloud transform and uncertainty reasoning. It provides new solutions for many basic problems in data mining and knowledge discovery, such as concept and knowledge representation, transition between quality and quantity, concept synthesization and resolution, concept and concept hierarchy generation from data, etc. Clod model is a model of the uncertain transition between a linguistic term of a qualitative concept and its numerical representation. Cloud model represents a qualitative concept with three digital characteristics, expected value, entropy and hyper entropy, which integrate the fuzziness and randomness of a linguistic term in a unified way. This paper presents the fundamentals of cloud theory and its applications in spatial data mining and knowledge discovery, focusing on the cloud models and their algorithms.

Radiography is a technique that acts as a quality control for many products. Poor quality of radiographic image becomes an obstacle for interpreter to give accurate evaluation. The problem of noise existence and low image resolution makes the radiographic analysis more difficult. Image enhancement can be applied to reduce this problem for better image visualization. Therefore, a study was carried out to enhance the quality of radiographic image on porosity with different voltage and current to capture the image. In this paper, a set of digital radiographic weld flaws on porosity image was applied with multiple smoothing techniques such as median, average and gaussian low pass filters to remove noise. Then, the combination of top hat and bottom hat morphological techniques was used as contrast enhancement. The performance of enhanced image was evaluated quantitatively using SNR and PSNR. The experimental results indicate some improvements in the quality of radiographic image in which the defect is more clearly seen as compared to the original image. The proposed technique shows that the lowest voltage and current used can give the best image quality based on SNR and PSNR and hence can reduce the energy.

This paper proposes an efficient hash table, named PRHMTF (Pseudo Random Hashing-Move to Front), to maintain a large number of simultaneous TCP connections in highspeed networks. Firstly, we design a hash function PRH by defining connection identifier as its input keyword and selecting suitable operators to compute the keyword. To resolve hash collision efficiently, we apply MTF heuristic to improve the traditional chaining resolution in virtue of network traffic locality. Finally, we evaluate the PRH-MTF connection table by experiments with high-speed network traffic trace. Experimental results indicate that the PRH-MTF connection table performs lookup operations better than the traditional simple XOR sorted one.

This paper presents an automatic method for Silence/Sonorant/Non-Sonorant detection based on multi-resolution spectral analysis (MRS) and ANOVA method. Our method is composed of two parts. The first is calculation of the MRS by combining several FFT of different lengths. The second is an automatic Silence/Sonorant/Non-Sonorant detection by calculating a classical statistics method such as Standard Deviation and Mean and a statistical test such as the Analysis of Variance ANOVA of each N frames of the MRS FFT. We used our Visual Assistance of Speech Processing (VASP) System applied to a corpus. This corpus was in French Belgian pronounced by Belgian speakers. The analysis of the obtained results shows that automatic Silence/Sonorant/Non-Sonorant detection based on MRS provides better results compared to classical spectral analysis of the corpora used. Classifications with ANOVA was better then the classical methods such as Standard Deviation and Mean.

Dynamic processing of multi-resolution model may raise real-time running efficiency of the large-scale complex model in virtual scene. It's the key how to accurately recover to the original model after multi-resolution model is simplified and refined in repeated operation. In this paper, simplified model based on removed edge of the multi-resolution model, to improve the vertex table of data structure, saving data of last simplified model by way of spherical coordinates. When reverse processing the last model can be easy to restore, while repairing the topology information to ensure the model correctly.

To solve the conflicts among the sample points, processing time and frequency resolution while testing the micro-deviation of the resonance hydrogen sensor's resonance frequency, so a system focused in DSP and DDS (Direct Digital Synthesis) chips has been designed to calibrate and improve the frequency resolution by utilizing the high resolution characteristics of DDS signal frequency. Meanwhile, the theory for arithmetic is analyzed and the tests for arithmetic and sample points have been fulfilled. Proved by the experiments, the frequency resolution can be improved and the calculating time is reduced at the same time by the arithmetic.

Among the conventional algorithms of colorization, color transfer algorithm is the most common one. However, the traversal matching of each pixel is inevitable in the case of target color image. Though existing some improved methods of color correlation based, they make little sense on large resolution images and grayscale video rendering. This paper focuses on the use of CUDA, GPU general parallel computing platform, which is rapidly developed in recent years, accelerating colorization and adopting Secondary Coloring method to eliminate the effects of noise. The experimental results imply better acceleration.

The process of inpainting is to reconstruct the lost or deteriorated parts of images. The reconstruction of missing data in very high spatial remote sensed image is of great challenge due to its complexity. Remotely sensed Very High Resolution (VHR) images may be partly contaminated by cloud and accurate reconstruction of such images is of great problem. In this paper two strategies were proposed one for cloud removal and other for reconstruction of missing regions to improve the accuracy. The cloud removal problem is achieved by means of bandelet transform and multiscale geometrical grouping algorithm. This algorithm aims at removing the cloud contaminated portions from the VHR images. Then Exemplar based inpainting strategy (approach) is used for reconstruction of missing regions. The two algorithms used here are very simple and efficient results can be obtained.