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Recently, 3D deep learning models have been shown to be susceptible to adversarial attacks like their 2D counterparts. Most of the state-of-the-art (SOTA) 3D adversarial attacks perform perturbation to 3D point clouds. To reproduce these attacks in the physical scenario, a generated adversarial 3D point cloud need to be reconstructed to mesh, which leads to a significant drop in its adversarial effect. In this paper, we propose a strong 3D adversarial attack named Mesh Attack to address this problem by directly performing perturbation on mesh of a 3D object. In order to take advantage of the most effective gradient-based attack, a differentiable sample module that back-propagate the gradient of point cloud to mesh is introduced. To further ensure the adversarial mesh examples without outlier and 3D printable, three mesh losses are adopted. Extensive experiments demonstrate that the proposed scheme outperforms SOTA 3D attacks by a significant margin. We also achieved SOTA performance under various defenses. Our code is available at: https://github.com/cuge1995/Mesh-Attack., Comment: 8 pages, 6 figs

As 3D point cloud analysis has received increasing attention, the insufficient scale of point cloud datasets and the weak generalization ability of networks become prominent. In this paper, we propose a simple and effective augmentation method for the point cloud data, named PointCutMix, to alleviate those problems. It finds the optimal assignment between two point clouds and generates new training data by replacing the points in one sample with their optimal assigned pairs. Two replacement strategies are proposed to adapt to the accuracy or robustness requirement for different tasks, one of which is to randomly select all replacing points while the other one is to select k nearest neighbors of a single random point. Both strategies consistently and significantly improve the performance of various models on point cloud classification problems. By introducing the saliency maps to guide the selection of replacing points, the performance further improves. Moreover, PointCutMix is validated to enhance the model robustness against the point attack. It is worth noting that when using as a defense method, our method outperforms the state-of-the-art defense algorithms. The code is available at:https://github.com/cuge1995/PointCutMix, Comment: 8 pages,5 figures

Deformable Object Manipulation (DOM) is an important field of research as it contributes to practical tasks such as automatic cloth handling, cable routing, surgical operation, etc. Perception is considered one of the major challenges in DOM due to the complex dynamics and high degree of freedom of deformable objects. In this paper, we develop a novel image-processing algorithm based on Gabor filters to extract useful features from cloth, and based on this, devise a strategy for cloth flattening tasks. We evaluate the overall framework experimentally, and compare it with three human operators. The results show that our algorithm can determine the direction of wrinkles on the cloth accurately in the simulation as well as the real robot experiments. Besides, the robot executing the flattening tasks using the dewrinkling strategy given by our algorithm achieves satisfying performance compared to other baseline methods. The experiment video is available on https://sites.google.com/view/robotic-fabric-flattening/home

Learning from Demonstration (LfD) aims to encode versatile skills from human demonstrations. The field has been gaining popularity since it facilitates knowledge transfer to robots without requiring expert knowledge in robotics. During task executions, the robot motion is usually influenced by constraints imposed by environments. In light of this, task-parameterized LfD (TP-LfD) encodes relevant contextual information in reference frames, enabling better skill generalization to new situations. However, most TP-LfD algorithms require multiple demonstrations in various environment conditions to ensure sufficient statistics for a meaningful model. It is not a trivial task for robot users to create different situations and perform demonstrations under all of them. Therefore, this paper presents a novel concept for learning motion policies from few demonstrations by finding the reference frame weights which capture frame importance/relevance during task executions. Experimental results in both simulation and real robotic environments validate our approach., Comment: Submitted to RA-L

Tracking tasks based on deep neural networks have greatly improved with the emergence of Siamese trackers. However, the appearance of targets often changes during tracking, which can reduce the robustness of the tracker when facing challenges such as aspect ratio change, occlusion, and scale variation. In addition, cluttered backgrounds can lead to multiple high response points in the response map, leading to incorrect target positioning. In this paper, we introduce two transformer-based modules to improve Siamese tracking called DASTSiam: the spatio-temporal (ST) fusion module and the Discriminative Augmentation (DA) module. The ST module uses cross-attention based accumulation of historical cues to improve robustness against object appearance changes, while the DA module associates semantic information between the template and search region to improve target discrimination. Moreover, Modifying the label assignment of anchors also improves the reliability of the object location. Our modules can be used with all Siamese trackers and show improved performance on several public datasets through comparative and ablation experiments.

The authenticated broadcast is simulated in the bounded-degree networks to provide efficient broadcast primitives for building efficient higher-layer Byzantine protocols. A general abstraction of the relay-based broadcast system is introduced, in which the properties of the relay-based broadcast primitives are generalized. With this, fault-tolerant propagation is proposed as a building block of the broadcast primitives. Meanwhile, complementary systems are proposed in complementing fault-tolerant propagation and localized communication. Analysis shows that efficient fault-tolerant propagation can be built with sufficient initiation areas. Meanwhile, by integrating fault-tolerant propagation and localized communication, efficient broadcast primitives can be built in bounded-degree networks., Comment: 8 pages, 2 figures

For reaching fast and efficient self-stabilizing Byzantine pulse synchronization (SSBPS) upon the bounded-delay message-passing networks, we consider the peaceable SSBPS problem where the resource occupation in the stabilized system is required to be as sparse as possible and the stabilization of the system is required to be as fast as possible. To solve it, the decoupled absorption process and emergency process are investigated under a general framework. The constant-time two-stage absorption process and more than one kind of emergency process are provided in integrating the merits of temporal trails, approximate agreements, deterministic and randomized Byzantine agreements, and self-stabilizing protocols. With this, not only SSBPS but self-stabilizing Byzantine clock synchronization can be fast established and efficiently maintained. In the optimal-resilient basic solutions, the deterministic linear stabilization time and the stabilized resource occupation are all optimized to those of the underlying primitives, which is optimal in the presence of Byzantine faults under the classical static adversary. In the hybrid solutions, faster stabilization can be expected with a worst-case deterministic stabilization time. In all solutions, the stabilized resource occupation is at most at the order of approximate agreement, which is a good property in considering real-world ultra-high-reliable hard-real-time applications where pulse synchronization is expected to be established before all upper-layer functions and to be efficiently maintained when the upper-layer functions are in service., Comment: 23 pages, 3 figures

Previous work has shown that 3D point cloud classifiers can be vulnerable to adversarial examples. However, most of the existing methods are aimed at white-box attacks, where the parameters and other information of the classifiers are known in the attack, which is unrealistic for real-world applications. In order to improve the attack performance of the black-box classifiers, the research community generally uses the transfer-based black-box attack. However, the transferability of current 3D attacks is still relatively low. To this end, this paper proposes Scale and Shear (SS) Attack to generate 3D adversarial examples with strong transferability. Specifically, we randomly scale or shear the input point cloud, so that the attack will not overfit the white-box model, thereby improving the transferability of the attack. Extensive experiments show that the SS attack proposed in this paper can be seamlessly combined with the existing state-of-the-art (SOTA) 3D point cloud attack methods to form more powerful attack methods, and the SS attack improves the transferability over 3.6 times compare to the baseline. Moreover, while substantially outperforming the baseline methods, the SS attack achieves SOTA transferability under various defenses. Our code will be available online at https://github.com/cuge1995/SS-attack, Comment: 10 pages

Message propagation is fundamental in constructing distributed systems upon sparsely connected communication networks. For providing easy message propagation primitives, the mutual-exclusive propagation (MEP) of one-bit messages is investigated with a simplified discrete system model. Inspired by natural propagation systems, efficient self-stabilizing periodic MEP processes are proposed with the MEP systems. For handling the worst-case scenarios, the MEP systems are generally analyzed with formal proofs upon arbitrarily connected networks. It shows that the MEP systems can be stabilized with arbitrary initial system states within a short bounded time. Meanwhile, the numeric simulation shows that the propagation errors can be significantly reduced if the message delays are randomly distributed. Propagation patterns are also discussed in further deriving finer propagation results in the MEP systems. It shows that bounded clock drifts and some benign faults can be well handled in the MEP systems. Featured by its very simple mechanism, the proposed MEP primitive can be employed as a practical building block of upper-layer self-stabilizing synchronous systems., Comment: 12 pages, 7 figures

This paper presents a topology optimization approach for the surface flows on variable design domains. Via this approach, the matching between the pattern of a surface flow and the 2-manifold used to define the pattern can be optimized, where the 2-manifold is implicitly defined on another fixed 2-manifold named as the base manifold. The fiber bundle topology optimization approach is developed based on the description of the topological structure of the surface flow by using the differential geometry concept of the fiber bundle. The material distribution method is used to achieve the evolution of the pattern of the surface flow. The evolution of the implicit 2-manifold is realized via a homeomorphous map. The design variable of the pattern of the surface flow and that of the implicit 2-manifold are regularized by two sequentially implemented surface-PDE filters. The two surface-PDE filters are coupled, because they are defined on the implicit 2-manifold and base manifold, respectively. The surface Navier-Stokes equations, defined on the implicit 2-manifold, are used to describe the surface flow. The fiber bundle topology optimization problem is analyzed using the continuous adjoint method implemented on the first-order Sobolev space. Several numerical examples have been provided to demonstrate this approach, where the combination of the viscous dissipation and pressure drop is used as the design objective.

In extending fast digital clock synchronization to the bounded-delay model, the expected constant time Byzantine pulse resynchronization problem is investigated. In this problem, the synchronized state of the system should not only be deterministically maintained but be reached from arbitrary states with expected constant time in the presence of Byzantine faults. An intuitive geometric representation of the problem is introduced, with which the classical approximate agreement, randomized Byzantine agreement, and random walk are integrated with some geometric operations. Efficient realizations are also provided for practical uses. Compared with the state-of-the-art solutions, the assumed common pulses need not be regularly generated, the message complexity can be lowered as approximate agreement, and the expected stabilization time is optimal. With this, the provided solution can efficiently convert irregularly generated common pulses to self-stabilizing Byzantine pulse synchronization., 9 pages, 4 figures, submitted to Elsevier

This paper proposes a general approach to design automatic controls to manipulate elastic objects into desired shapes. The object's geometric model is defined as the shape feature based on the specific task to globally describe the deformation. Raw visual feedback data is processed using classic regression methods to identify parameters of data-driven geometric models in real-time. Our proposed method is able to analytically compute a pose-shape Jacobian matrix based on implicit functions. This model is then used to derive a shape servoing controller. To validate the proposed method, we report a detailed experimental study with robotic manipulators deforming an elastic rod.

Selecting safe landing sites in non-cooperative environments is a key step towards the full autonomy of UAVs. However, the existing methods have the common problems of poor generalization ability and robustness. Their performance in unknown environments is significantly degraded and the error cannot be self-detected and corrected. In this paper, we construct a UAV system equipped with low-cost LiDAR and binocular cameras to realize autonomous landing in non-cooperative environments by detecting the flat and safe ground area. Taking advantage of the non-repetitive scanning and high FOV coverage characteristics of LiDAR, we come up with a dynamic time depth completion algorithm. In conjunction with the proposed self-evaluation method of the depth map, our model can dynamically select the LiDAR accumulation time at the inference phase to ensure an accurate prediction result. Based on the depth map, the high-level terrain information such as slope, roughness, and the size of the safe area are derived. We have conducted extensive autonomous landing experiments in a variety of familiar or completely unknown environments, verifying that our model can adaptively balance the accuracy and speed, and the UAV can robustly select a safe landing site., Comment: Submitted to ICRA 2021

A bend-insensitive wideband multimode fiber has been fabricated via PCVD process. The fiber is designed to support four SWDM channels at speeds of over 25 Gb/s between 850 nm and 953 nm to realize a 150 meters transmission link at least.

The paper introduced latest ITU-T G.654.E fiber sepecification and typical G.654.E profile design. Our novel ultra low loss & large effective area fiber attenuation and cabling performance were also discussed. in the recent two G.654.E terrestrial cable projects of china, the PCVD G.654.E fiber shows the huge advantages of link attenuation and effective area than standard G.652.D fiber. G.654.E industry chain is matured and can be promoted in terrestrial network.

4×25 Gbps SWDM transmission is demonstrated over the novel bend-insensitive wideband multimode fibers in the 850-950 nm wavelength range. The wideband multimode cable shows negligible macro-bending loss with 2 turns at bending radius of 7.5 mm.

Integrated layout optimization of multi-component structures under static loads and random excitations is studied in this paper. Dynamic responses are obtained by using the mode superposition method, and the prestress effect introduced by the static loads is taken into account in the analyses of dynamic responses. Locations of embedded components and pseudo-densities related to supporting structure are chosen as design variables. Design sensitivities of the dynamic responses with respect to the pseudo-densities are analytically derived. The optimization algorithm GCMMA (Global Convergent Method of Moving Asymptotes algorithm) is used to minimize simultaneously the static strain energy and dynamic responses. Three numerical examples are presented to show the validity of the optimization procedure and its potential application in practical designs.

This paper proposes an angular acceleration estimation method based on the complementary filter theory for flight control. As the feedback control of angular acceleration signals can significantly increase system robustness and improve system performance, this field of research has recently encountered a growing popularity. Unfortunately, there is no perfect method or technique for obtaining angular acceleration signals. Thus, a novel estimation method is proposed in the paper. It is a data fusion method combining the model prediction method and the differential method based on the proposed complementary filter structure, which skillfully avoids the differential operation and eliminates the influence of model uncertainties and system disturbances through the feedback of angular velocity signals. Hence, the proposed method can not only improve the signal performance but also guarantee the signal's correctness. An experiment is conducted in a 3-axes flight simulator to check the effectiveness and practicability of the proposed estimation method. The results of our experiment show that the proposed angular acceleration method based on the complementary filter method can effectively estimate the true value of angular accelerations and greatly improve the signal performance.

The prop-hanging control of the fixed-wing aircraft can enable the vehicle to improve the cruise performance and hover ability. The prop-hanging control of the thrust vector vehicle would be a challenging problem, for the reason that it is a system with properties of inherent instability, coupling, non-linearity and non-minimum phase characteristics. To deal with these complex problems, a hybrid Nonlinear Dynamic Inversion (NDI) method is proposed in this paper. Inspired by NDI, Incremental NDI and angular acceleration feedback control methods, the hybrid NDI method includes three parts: feedforward control, proportional control and logical integral control, which can enable the system to have a rapid response in the transient phase and a satisfactory performance in the steady state. A numerical simulation is conducted to test the performance and the robustness of the proposed control method, and a Hardware-in-the-loop simulation is also conducted to check the practicability and effectiveness in the actual application. Simulation results show that the proposed control method can effectively improve system robustness and is practical.

A new layout using wing disk solar aircraft concept with several wings around the disk fuselage is proposed in the research. The wings and fuselage can both provide lift during the overall rotation and forward flying. Propellers at the outer end of the wings are used to overcome the resisting moment, cyclical changes in the power forces, and deflection angle of ailerons to overcome the drag and roll torque in forward flight, which can also control the position and attitude. Aerodynamic analysis is developed based on rotor blade element theory and CFD method. The energy absorption and consumption and weight estimate of each subsystem are taken into account, and an optimization is laid out to meet the cruising flight requirement by iterative design.

A new type of multimode fiber with OM4 performance over 850∼950nm operational windows is presented. This bend-insensitive wideband multimode fiber is designed to support at least 4 SWDM channels for 100Gbps or even 400Gbps transmission system.

A novel PCN bond containing azaphosphorine, 5-(4-hydroxy)anilinomethyl-1,3-di(4-hydroxy)phenyl-1,3,5-diazaphosphorinane (ADDPP-OH), which could be used as both a cocuring agent and a flame-retarding agent for epoxy resins (EPs), was synthesized from tetrakis(hydroxymethyl)phosphonium sulfate and characterized by FTIR, 1H-NMR, 13C-NMR, 31P-NMR, and so on. Compared with the pure EP, the ADDPP-OH–EP composites showed increased decomposition temperatures and char yields. When the content of ADDPP-OH was 10 wt %, the cured EP composite possessed a limiting oxygen index value of 33.7% and passed the V-0 rating of the UL-94 test. The mechanical properties of the ADDPP-OH–EP composites was improved because of the increased crosslinking density. In addition, the morphology of the residual char indicated an intumescent and multiporous structure in the inner space and a compact and continual appearance in the outer layer; this was important in preventing the materials from burning further. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45721.

We propose two nonlinear approaches for the autonomous transition control of two vertical/short takeoff and landing aircraft. The first aircraft, referred to as the V-1 aircraft, is a fixed-wing fighter equipped with a vectored thrust and lift fan. The second aircraft is a tilt rotor. We provide nonlinear models for the transition from hover to forward flight. Both control problems are nonlinear, nonaffine, and have redundant inputs. Furthermore, some control inputs must reach specified end values when the transition has been completed. However, there is a key difference between the two aircraft. The V-1 aircraft can be controlled to rapidly increase velocity and pitch angle simultaneously, whereas the tilt rotor aircraft cannot, because linear and angular acceleration require conflicting control inputs from hover. For the V-1 aircraft, a method is applied whose key point is that a new controlled variable is appended to decrease the redundancy of the control inputs. For the tilt rotor aircraft, a second method is applied that transfers the problem into a two-time-scale problem. Nonlinear optimization is adopted to make the specified input approach the specified end value. We also consider problems associated with cases in which insufficient control power limits the ability of the aircraft to achieve commanded controlled variable rates. Simulations show that both approaches achieve the transition control successfully.

Thrust vector can effectively improve the fighter's maneuverability and flight safety, increasing the survival rates in the air combat. As the key component of thrust vectors, the turbojet engine's dynamics and characteristics have a great influence on the performance and control of thrust vectors. This paper would model the dynamics of a small scale turbojet engine through experiment and identification. An experiment platform of the turbojet engine was developed to test its dynamic responses and characteristics. Through the analysis of the experiment data, we find that the dynamics of the turbojet engine can be divided into two parts: the dynamic response from the throttle commands to the engine rotor speed and the nonlinear function between the rotor speed and the engine thrust. The proposed model was checked and verified through the experiment data, and the results show that the model can accurately and effectively represent the turbojet engine's dynamics and characteristics. The model describes the turbojet engine's input/output response with only two parameters, which is simple and convenient for us to understand its input/output characteristics and make appropriate usage.

The Generalized Proportional Integral Observer (GPIO), which is a generalized high order Extended State Observer (ESO), has drawn much attention from both the industry and academia recently. This paper explores the characteristics of GPIO for the linear, time-invariant (LTI) plants using the frequency response method. It shows that the high order GPIO not only estimates the total disturbance and its derivatives, but also contributes to the closed-loop system type. Theoretical analysis and simulation results agree in that different GPIO orders have little impact on the tracking performances and the control signal, but more augmented state variables in the GPIO can lead to stronger disturbance rejection and smaller sensitivity function, at the cost of decreasing stability margins, increasing sensitivity to measurement noises and increasing the computational complexity. The conclusions could be useful for the practitioners and researchers who need clarity in the GPIO order selections.

Due to their concentrated windings and modular topology, permanent-magnet fault-tolerant (PMFT) motors inherently offer decoupling phases and fault-tolerant capability. According to open- and short-circuit faults, and in order to keep torque performance invariant during the faulty operation, two relevant fault tolerant strategies are separately presented, derived, analyzed and tested. The effectiveness and validity of fault-tolerance and the strategies of the motor are verified.

With multiple single-phase lanes, and each driven by independent H-bridge power converters, permanent-magnet fault-tolerant motors inherently offer isolated phases and fault-tolerant capability. It is assumed that there is an open-circuit fault detected in the Phase A. In order to keep torque performance invariant during the faulty operation, a pertinent fault tolerant strategy is separately presented, derived and tested. Based on a series of experiments on a test bench, the effectiveness and validity of fault-tolerant capability and the strategy of the motor are verified.

The optimal layout of supports is one of the key factors that dominates static and dynamic performances of the structure. In this work, supports are considered as elastic springs. The purpose is to carry out layout optimization of supports by means of topology optimization method. The technique of pseudo-density variables that transforms a discrete-variable problem into a continuous one is used in order that the problem is easily formulated and solved numerically. In this formulation, a power law of the so-called solid isotropic material with penalty model is employed to approximate the relation between the element stiffness matrix and density variable. Such a relation makes it easy to establish the computing scheme and sensitivity analysis of natural frequency. Support layout design that corresponds to optimization of boundary conditions is studied to maximize the natural frequency of structures. Numerical results show that reasonable distributions of supports can be generated effectively.

Vertical take-off and landing (VTOL) aircraft has the merits of both fixed-wing and rotary-wing aircraft. Tail-sitter is the simplest way for the VTOL maneuver since it does not need extra actuators. However, conventional tail-sitting airplanes made by propellers or duct fans have less thrust and efficiency. In this paper a conceptual thrust-vectored unmanned tail-sitter (CTUT) aircraft which is controlled by no control surfaces but only with two thrust vectors is introduced. However, the system of hovering control for a tail-sitter UAV is like a 3-D inverse pendulum, which is unstable and quite difficult to control against the gust load in traditional PID controllers. In this paper, the synthesized system model including thrust-vectored tail-sitter aircraft model, actuator system and gust model is developed. The LQG/LTR control for robust hovering against gust load is proposed. The results show that the controller designed successfully compensates the errors generated by gust.

Presents an electric loading system without inertia disk for actuators that adopts a torque-loading structure with disc permanent magnet synchronous torque motor, which connects directly with the actuator under test, eliminating the inertia disk damping. It employs Wheatstone bridge circuit for measuring torque, and sticks strain gauges directly on the output shaft of the torque motor, removing the inertia of the torque sensor. Also, it establishes a model of disc permanent magnet synchronous torque motor, and uses the SVPWM (space vector pulse width modulation) method for the motor torque control. The simulation results of step response show that the system, without the need for bulky energy conversion device, realizes any transient current amplitude to control, through the use of sine wave current for driving, and reduces significantly the torque ripple, inhibits effectively the excess force in loading process. This electric loading system is simple in its structural design, and can improve model accuracy. Meanwhile, SVPWM vector control method improves the dynamic quality and control precision of the loading system.

As a media of display, the screen is really different with paper in the property. The layout specification of paper is mature. However, it could not be fully applicable of the screen layout design and must be made corresponding adjustments. Aiming at this problem, this article, based on a series of experiments of Chinese texts and the analysis on the relation between Chinese texts and medium, aiming at the reading efficiency, discusses the screen typeface typography from the relations among type size, tracking and row space and character background color, and puts forward the relative solutions.

Many artists and designers have long been trying to convert music into visual arts. On the basis of the author's design practice, this article focuses on the analysis of the commonality of music and visual arts and divides from the aspect of synesthesia the methods adopted in the visualization of music into three categories: direct relevance, formal relevance and emotional relevance.

A triple modular redundant (TMR) control system achieves high reliability by replicating data and all processing at three independent nodes, so this control system is widely applied in many fields. Loongson Micro Computer Unite (MCU) is designed by The Institute of Computational Mathematics and Scientific/Engineering Computing of Chinese Academy of Sciences which hold property right of Loongson MCU. In this paper, performance of two foreign TMR systems are analyzed firstly, then a TMR control system basing on Loongson 2E chips to handle a single arbitrary node failure is designed. Method of signal vote and process of program synchronization is demonstrated by simple example with three input signals and one output signal.

In this article, design and implement of anti-impact and over-loading projectile conform al antennas for GPS is introduced. First step, material and thickness of base for antennas should be chosen, then width and length of antennas is calculated, next step to polarize antennas and give location of feed points. The designed antenna is emulated and analyzed by IE3D software, and certain parameter is modulated. At last anti-impact and over loading experiment s is carried to prove designed antenna could be applied in execrable condition, and location experiments is carried to show actual effect of designed antenna.

Dual-redundancy EMA is studied in this paper for improving the reliability and safety of aircraft. The differential sport synthesization scheme is proposed for solving load-unbalance problem when operating with the mode of dual-redundancy, which is a mechanical structure to turn two outputs into one output without load-averaging controller, and this structure can decrease the design difficulty of controller to improve the stability and reliability of system, moreover, local-redundancy design is done in this paper, it can still guarantee some redundancy in system when some faults appear in one channel. In addition, in order to simplify design, the method of truth-table is adopted to code 6 PWMs for three phase VSI bridge, moreover, the rotator signal and PWM are used together to forms a BIT module for system, and it can realize fault detection and diagnosis for dual-redundancy EMA. The PD controller with variable parameters is presented to compensate nonlinear factors of system. The experimental results validate its system design, and show that the prototype of DR-EMA has fine performance, high stability and reliability.

This article presents the implementation of mission planning for Unmanned Aerial Vehicles (UAV). A safe-ring method for real-time path planning of UAV is proposed. Threat modeling, different types of reconnaissance are discussed before the algorithm is described. Kinematical constraints are satisfied with a model which has the same structure as the physical vehicle. A feasible state trajectory was generated, which can be followed by a standard autopilot. The demonstration of the mission planning system shows that the implementation is efficient and satisfying.

Sensor image registration is one of important problems in sensor fusion, it is the task of finding the correct mapping of one sensor image onto another. In this paper, the sensor image registration problem is approached as a optimization problem, then an appropriate fitness function is proposed to evaluate the mapping parameter set and several optimization methods (genetic algorithms, simulated annealing, hybrid strategy GASA) are adopted to solve this problem automatically. The experiment indicates the feasibility of the registration methods which are insensitive to noise. Among them, GASA shows good performance because of its rapid convergence.

The eigenstructure assignment method for a continuous time-variant uncertain system based on linear matrix inequality (LMI) is investigated in this paper. The result can be combined with other LMIs for more system indices. All these LMIs can form a satisfying controller design method for continuous time-variant uncertain systems.