Biopsy needle artifact localization in MRI-guided robotic transrectal prostate intervention

Recently a number of robotic intervention systems for magnetic resonance image (MRI)-guided needle placement in the prostate have been reported. In MRI-guided needle interventions, after a needle is inserted, the needle position is often confirmed with a volumetric MRI scan. Commonly used titanium needles are not directly visible in an MRI, but they generate a susceptibility artifact in the immediate neighborhood of the needle. This paper reports the results of a quantitative study of the relationship between the true position of titanium biopsy needle and the corresponding needle artifact position in MRI, thereby providing a better understanding of the influence of needle artifact on targeting errors. The titanium needle tip artifact extended 9 mm beyond the actual needle tip location with tendency to bend toward the scanner's B (0) magnetic field direction, and axially displaced 0.38 and 0.32 mm (mean) in scanner's frequency and phase encoding direction, respectively.     

An MRI-compatible endonasal surgical robotic system: Kinematic analysis and performance evaluation

Neurosurgical interventions are often complicated and require procedure-specific solutions for a better outcome. A pituitary tumor is one of the common brain tumors resected by trans-sphenoidal surgery. Magnetic resonance imaging (MRI) provides better vision when compared to other imaging modalities. Simultaneous resection and imaging of pituitary tumors under MRI can improve the surgical outcome. Herein, we propose the first MRI-compatible robotic system for pituitary tumor removal via trans-sphenoidal/endonasal access. The presented system follows the current gold standard procedure of pituitary tumor resection and integrates it with a commercial MR scanner to provide a widely applicable system. The robotic system is the procedure-, anatomy-, and geometry-specific with 6-degree-of-freedom actuated by a bed-type actuation platform in the MRI room. A K-means clustering algorithm detects the tumor and develops and updates the brain model periodically during MR-guided interventions. The robot has procedure-specific stiffness changing capability with a unique stiffness-dependent kinematic model. The workspace subtended by the robotic system in all stiffness cases satisfies the workspace required for surgical procedures. The accuracy and repeatability of the robot are also in a desirable range. The procedure and patient-specific robot design are evaluated by in-vivo experiments in the live porcine under MRI. This work is a step toward a dual-arm surgical system for pituitary tumor removal under MRI guidance and experimental results validate the proposed solution and supplement further development to achieve a clinically applicable system.     

光电混合综合判别相关器自动跟踪系统

在本文中，作者回顾了综合判别函数基本理论，简要地介绍了用ＳＤＦ实现畸变不变相关的的技术途径。在此基础上，成功地将ＳＤＦ相关器应用于目标跟踪，并利用ＳＤＦ相关器构成了一个自动跟踪实验系统。实验结果证明：该系统具有比较好的收敛性和跟踪性能。     

An automated guided mechatronic tractor for path tracking of heavy-duty robotic vehicles

Nowadays, a large number of AGVs are needed to carry out repeating transport tasks in many manufacturing and warehouse industries. Their extensive application is influenced by several critical factors of equipment expense, vehicle maneuverability, energy efficiency and configuration flexibility, especially in a large-scale AGV system. In order to attain high dynamics and energy conservation while retaining low cost and flexible reconfiguration, mechatronics techniques are introduced to combine high-performance microcontrollers, low-power motors and short-range sensors with a light-weighted chassis, which results in a swift mechatronic tractor for automated guidance of a heavy-duty robotic vehicle on fixed guide paths. Analysis of load carrying for different wheels shows the tractor only carries a partial weight of the whole vehicle by using its suspension layer. Kinematics and dynamics properties of the vehicle actuated by the tractor are investigated, which explains the reasons why low-power motors and short-range sensors can be used for automated guidance of heavy-duty vehicles. When this tractor is equipped with different guiding sensors, such as a magnetic sensor or a camera, the corresponding magnetic or visual guided vehicle can be conveniently developed only by configuring tractors and other passive wheels within a vehicle frame. For instance, a low-cost magnetic sensor is used for the tractor and a magnetic guided vehicle prototype is developed based on it. Experiments of load carrying and path tracking are conducted by using this prototype. The experiment results show the tractor can actuate the heavy-duty vehicle with low power consumption and track its target paths with a fast dynamic response, which provides a possibility of decreasing cost and consumption still preserving maneuverability and flexibility by using mechatronics techniques.     

An energy sensitive system framework for cloud robotic network

Cloud robotic network (CRN) is an extension of the traditional robots, and its important significance is to use the Internet and cloud computing to overcome the limitations of single robot and enhance its computing power. As the core technology of CRN, how to achieve the full potential of computation off‐loading is a critical issue. Starting from the basic models of CRN, this paper studies the network architecture and the computation off‐loading method to solve this problem. Firstly, a relatively detailed system model is designed based on the characteristics of CRN to provide theoretical and quantitative basis for subsequent research. Then, based on the theory of connected dominating set, a distributed CDS construction algorithm PCDS is proposed, which provides a virtual backbone with more power for the network. Finally, an energy sensitive computation off‐loading method is proposed to improve the lifetime of the whole network while ensuring the execution time and energy loss of computational tasks. Simulation results show that the proposed framework can effectively improve the performance of CRN and prolong the lifetime to a certain extent.     

风光互补发电系统最大功率跟踪综述

风光互补发电系统的运行需要快速准确地进行最大功率点跟踪,为此综述了风光互补发电系统最大功率点跟踪的几种方法,包括在太阳能电池阵列部分日益成熟、改进和优化策略较多的扰动观察法、电导增量法和恒压控制法;风力发电机部分的叶尖速比控制法、功率信号反馈法、扰动观察法,分别说明了各种跟踪控制方法的优点和不足之处。最后探讨了最大功率点跟踪控制方法的发展思路,对该领域今后的研究方向做了展望。     

An animatronic system including lifelike robotic fish

This paper provides an outline of a new animatronic system, based on the technology of the flexible oscillating fin. The oscillating fin propulsion system was designed and constructed to be combined with a ship model. The system's feasibility has been confirmed by tank tests using the ship model. As a result, several advantages of the oscillating fin system have been found. A neural network was successfully applied for an identification of the ship model dynamics with the oscillating fin and its effectiveness was confirmed. The animatronic system is a computer-controlled biomechanically engineered model, rapidly gaining popularity throughout the world. We have developed aquatic robots with oscillating fins for the animatronics system to build a virtual aquarium. We have proposed an exhibition system for enhancing event spaces that includes an animatronic system for modern-day fish, coelacanths, and Cambrian-world creatures, able to swim under their own electric power.     

An adaptive low-angle tracking system

A system for source tracking down to a fraction of a beamwidth of a surface with unknown multipath reflecting properties is described. The system has three major features: 1) the multipath returns are decorrelated by frequency diversity; 2) an efficient broad-band multiple beam antenna design is employed such that the data are characterized by a highly symmetrical (Toeplitz) correlation matrix; 3) Burg's reflection coefficient technique is employed to obtain rapid convergence to the maximum entropy spectrum from which the target location is determined. Realistic simulations including imperfect decorrelation, antenna errors, and transient results show that the system can provide accurate low-angle estimates using a practical antenna and reasonable data-processing time.     

An adjunct tracking system for low altitude sector aircraft

This paper advances the concept of using slightly modified commercial ground broadcast TV signals to aid in tracking aircraft at low attitude near major airports. The modification of the TV signal is not major and will not affect normal TV operation. The resulting system should be of utility in augmenting air traffic control and could provide an important dual service role for commercial TV ground broadcast     

基于激光视觉传感器的机器人实时焊缝跟踪方法

为实现变姿态焊接过程的实时焊缝跟踪,提出基于机器人坐标系下绝对焊缝轨迹的实时跟踪算法.将线式激光传感器安装在机器人的法兰盘上,且位于焊枪运行的前方.焊接过程中,激光传感器连续采集焊缝位置信息,并结合手眼标定矩阵以及机器人实时姿态,将传感器采集的焊缝坐标转换到机器人基础坐标系下,从而形成空间绝对焊缝轨迹;再根据焊枪的当前...     

一种改进的点光源跟踪系统设计与实现

提出一种改进的点光源跟踪方案,采用MSP430F149作为主控制器,分光源发送端和光源跟踪端两部分研究。发送端发送lKHz频率的光,跟踪端用光敏三极管检测点光源信号,对其进行1KHz的带通滤波和A／D转换,然后分析点光源的移动方向,并控制舵机跟踪点光源。软件部分用基本控制和中心控制两种算法互相补充、交叉控制,提升了系统性能。测试结果表明,系统跟踪快速且准确、运行稳定。     

Comparative study of maximum power point tracking techniques for hybrid renewable energy system

The power generation demand is increasing day-by-day throughout the world, therefore, the use of hybrid systems becomes a significant solution. The hybrid renewable energy system (HRES) is used for delivering power in various regions in order to overcome intermittence of wind and solar resources. Because of increasing environmental problems, for example, greenhouse gas emission and energy cost have interested novel research into substitute methods in favour of electrical power generation. Maximum Power Point Tracking (MPPT) control method is a vast deal of novel research used for enhancing the efficiency of HRES. The authors have revealed that the hybrid techniques i.e. Global MPPT, fuzzy-neuro systems, Adaptive Neuro-Fuzzy Inference System (ANFIS), Perturbed and Observe (P&O) + Adaptive Neural Network (ANN) etc. can provide best results as compared to other MPPT control methods. This paper offering a state of art review of MPPT control techniques for HRES.     

Energy-efficient information routing in sensor networks for robotic target tracking

Target tracking problems have been studied for both robots and sensor networks. However, existing robotic target tracking algorithms require the tracker to have access to information-rich sensors, and may have difficulty recovering when the target is out of the tracker??s sensing range. In this paper, we present a target tracking algorithm that combines an extremely simple mobile robot with a networked collection of wireless sensor nodes, each of which is equipped with an unreliable, limited-range, boolean sensor for detecting the target. The tracker maintains close proximity to the target using only information sensed by the network, and can effectively recover from temporarily losing track of the target. We present two algorithms that manage message delivery on this network. The first, which is appropriate for memoryless sensor nodes, is based on dynamic adjustments to the time-to-live (TTL) of transmitted messages. The second, for more capable sensor nodes, makes message delivery decisions on-the-fly based on geometric considerations driven by the messages?? content. We present an implementation along with simulation results. The results show that our system achieves both good tracking precision and low energy consumption.     

An intelligent robotic system based on a fuzzy approach

This paper deals with a fuzzy-based intelligent robotic system that requires various capabilities normally associated with intelligence. It acquires skills and knowledge through interaction with a dynamic environment. Subsumption architectures, behavior-based artificial intelligence, and behavioral engineering for robotic systems have been discussed as new technologies for intelligent robotic systems. This paper proposes a robotic system with “structured intelligence”. We focus on a mobile robotic system with a fuzzy controller and propose a sensory network that allows the robot to perceive its environment. An evolutionary approach improves the robot's performance. Furthermore, we discuss the effectiveness of the proposed method through computer simulations of collision avoidance and path-planning problems     

Investigation of an array technique for robotic seam tracking ofweld joints

A noncontact optical preview sensing technique for possible application to a robotic seam tracking system is presented. This technique uses a structured laser illumination source: a SELFOC lens array (SLA) coupled to a fiberoptic and a phototransistor (photodetector) array. The experimental results with the SLA and fiberoptic array demonstrate the feasibility of linear fiberoptic array sensing of the weld joint. The intensity profiles acquired by the array were such that when combined with suitable data processing software routines, the sensing technique was able to provide satisfactory measurements of joint width and location of the centerline. An experiment demonstrates the viability of the approach for tracking of a weld seam. A clear profile containing the expected features was obtained at each cross-sectional location as the joint was traversed     

一种多视角跟踪系统中的自行标定方法

多视角的标定和自标定是多视角系统部署和应用中的重要限制环节.文章针对基于单应关系的多视角跟踪应用场景,提出了一种使用跟踪结果本身进行视角几何关系标定的方法,避免了预先标定环节,可以配合现有的各种跟踪算法.理论分析和仿真实验表明,此方法具有高效率、高可靠性、易于实施的特点.     

An integrated software system for hybrid flight simulation: The boeing hybrid simulator

The Boeing Hybrid Simulator is a general-purpose hybrid computer designed to provide a laboratory for the development of hybrid methods of solving a variety of aero-space problems as well as to support large-scale simulations. The first such simulation is a Flight Simulation Program which provides both a three-degrees-of-freedom missile performance analysis tool and a six-degrees-of-freedom missile subsystem design analysis tool. The 3D simulation was implemented by placing the integrations of the translational equations on the analog, utilizing the digital for function generation, some algebraic manipulations, and basic bookkeeping. The 6D was implemented by placing the integrations of the rotational equations on the analog and the integrations of the translational equations on the digital. Phase control was supplied on the analog in both cases. A hybrid oriented execute-time monitor system supported the simulations by 1) providing a flexibile man-machine relationship, 2) providing an automatic and manual control capability, and 3) reducing digital and analog setup time. It enabled the man at the console to bring system packages into computer memory either to temporarily displace the simulations or to tie in with them in such a way that activities closely related to the execution of the simulations occur at the end of frame calculations.     

A robotic system for blood sampling

A robotic system to take blood samples autonomously from the forearm is presented, and preliminary results are discussed which demonstrate its feasibility. Force/position profiles, while pressing a flat-headed probe against the surface of the skin, enable the determination of a vein's location to within 1 mm on a phantom. When a needle is inserted, the characteristic force/position profile, on puncturing the vein wall, is distinctive enough to implement automatic needle withdrawal to prevent overshoot. Future developments of the project are presented that provide both an autonomous blood sampling robot and a force-feedback surgical trainer     

An intelligent robotic system for rehabilitation of joints andestimation of body segment parameters

An an application of robotics in physical rehabilitation therapy, a robotic system consisting of two planar robot arms, each with two degrees of freedom, is considered. This robotic system, when coupled across a human joint, provides a vehicle for rehabilitation of the joint following surgery or trauma. A novel approach for estimation of body segment parameters is formulated that uses state and output information from the robot system to improve these estimates. In addition, redundant sensors are used to improve the accuracy of the estimates. The dynamic equations for a single robot arm are provided and the system is simulated. Therapeutic applications of the robotic system are discussed and the sensitivity of the measured forces with respect to the robot arm joint angles is studied in order to find an optimum orientation of the system for the best possible estimation. The application of this system to both rehabilitation and sports medicine is also discussed