Precise Robot Research Articles

Development and Evaluation of a Registration Methodology for Information-Guided Precision Robotic Laser Neurosurgery System

Development and Evaluation of a Registration Methodology for Information-Guided Precision Robotic Laser Neurosurgery System

1A1-E23 ばねパラレルメカニズムを用いた精密位置決めロボットの開発

In this paper, development of a high precision robot using a spring-parallel mechanism is described. The spring-parallel mechanism can be defined as a parallel mechanism using large deflective joint elements. A circular spring joint was introduced to a redundant parallel mechanism for testing the concept of the spring-parallel mechanism. Concept, basic analysis, kinematics and implementation of prototype are introduced in this paper.

Precision Robotic Coating Application and Thickness Control Optimization for F-35 Final Finishes

In order to meet the F-35 Joint Strike Fighter’s strict radar cross-section and weight requirements, stealth coatings must be applied to extremely precise thickness tolerances. To meet these unprecedented tolerances, Lockheed Martin Aeronautics Company has implemented a unique Robotic Aircraft Finishing System (RAFS). This paper details the capabilities of RAFS hardware for precision coating application as compared to legacy systems. The iterative process of optimizing spray parameters and robot programs for coating thickness control on challenging F-35 geometry is also presented. Finally, results from the first coating of a production aircraft at RAFS are compared with previous hand-spray results. In keeping with Security and International Traffic in Arms Regulations, restricted information on coating materials and tolerances is not presented.

One-dimensional single-mode fiber-optic displacement sensors for submillimeter measurements

We demonstrate the working principle of a one-dimensional intensity-based fiber-optic displacement sensor. The sensor consists of one receiving fiber, which is moved laterally in the optical field emitted by an emitting fiber. It is shown numerically that the sensor response is highly linear (nonlinearity error of 0.1 to 2%) for a wide range of travel (2.24 to 860 microm). The sensor response is also simulated experimentally using a highly precise robot, the results of which correspond very closely to numerical ones. Linearity, travel, and sensitivity are experimentally determined for different gaps between the emitting and the receiving fibers (10 microm to 10 mm). A design chart that includes the nonlinearity error (0.5% to 2%), the travel (2.78 to 860 microm), the sensitivity (0.032 to 0.37 dB/microm), and the gap distance (1 to 10 mm) is finally proposed.

One-dimensional single-mode fiber-optic displacement sensors for submillimeter measurements

We demonstrate the working principle of a one-dimensional intensity-based fiber-optic displacement sensor. The sensor consists of one receiving fiber, which is moved laterally in the optical field emitted by an emitting fiber. It is shown numerically that the sensor response is highly linear (nonlinearity error of 0.1 to 2%) for a wide range of travel (2.24 to 860 μm). The sensor response is also simulated experimentally using a highly precise robot, the results of which correspond very closely to numerical ones. Linearity, travel, and sensitivity are experimentally determined for different gaps between the emitting and the receiving fibers (10 μm to 10 mm). A design chart that includes the nonlinearity error (0.5% to 2%), the travel (2.78 to 860 μm), the sensitivity (0.032 to 0.37 dB/μm), and the gap distance (1 to 10 mm) is finally proposed.

Enhancement of positioning accuracy of industrial robots with a reconfigurable fine-positioning module

Abstract Conventional industrial robots achieve a high flexibility by low investment costs, but they are limited in absolute positioning accuracy. The costs for the introduction of a new special high precision robot for micro-handling are very high, where the workspace is limited to small areas. For handling operations, best results according velocity, precision and costs can be achieved with SCARA-type robots. Therefore, the introduction of a fine-positioning module for the enhancement of positioning accuracy of robots in the micro-handling techniques, become indispensable. The most micro-handling systems on the market have been designed for individual work-pieces. With our proposed fine-positioning module, we get a reconfigurable robot system for the execution of different handlings tasks both in the micro- and meso-scale 2 in the industrial automation. To increase the flexibility of the robot system, the handling system is equipped with a tool change system, which allows an automated couple of the fine-positioning module with the Scara Robot. At this robot system, the Scara Robot will be used for coarse movements, and the fine-positioning module for very accurate positioning tasks. The fine-positioning module is equipped with a microscope, which enables in combination with an image processing system relative positioning technique, object recognition and measurements simultaneously. Handling of micro-objects and measurements are the major operations, which can be executed by the fine-positioning module.

Dynamic Modeling of Robotics for Various Regions of Speed (DMRS)

The existing heavy rigid manipulators are shown to be inefficient in terms of power consumption or speed with respect to the operating payload. Also, the operation of high precision robots is severely limited by their dynamic deflection, which delays subsequent operations, thus conflicting with the demand of increased productivity. These conflicting requirements between high speed and high accuracy have rendered the robotic assembly task a challenging research problem. The choice of modeling techniques and dynamic analysis based on the operating regions of robotic speed plays effective factor for economical computation and efficient performance for the robotic job in question. Consequently, the modeling of robots can be classified into three main domains, which are rigid linkage domain, Semi-elastic linkage domain and Flexible linkage robotics domain. A numerical case study is presented to investigate that concept.

Stereoscopic human interfaces

This article focuses on the use of stereoscopic video interfaces for telerobotics. Topics concerning human visual perception, binocular image capturing, and stereoscopic devices are described. There is a wide variety of video interfaces for telerobotic systems. Choosing the best video interface depends on the telerobotic application requirements. Simple monoscopic cameras are good enough for watching remote robot movements or for teleprogramming a sequence of commands. However, when operators seek precise robot guidance or wish to manipulate objects, a better perception of the remote environment must be achieved, for which more advanced visual interfaces are required. This implies a higher degree of telepresence, and, therefore, the most suitable visual interface has to be chosen. The aim of this article is to describe the two main aspects using stereoscopic interfaces: the capture of binocular video images, according to the disparity limits in human perception and the proper selection of the visualization interface for stereoscopic images.

The Broadband In‐Water Structural Acoustics of Unexploded Ordinance

The Laboratory for Structural Acoustics (LSA) at the Naval Research Laboratory consists of a 1 million gallon, deionized water, indoor cylindrical tank (17m diameter by 15m deep). The key features include: 1) vibration and temperature isolation, 2) feedback controlled heating and adiabatic materials (temperature variability <0.01°C), and 3) reverberation reducing anechoic materials. This laboratory has computer controlled robotic scanners and manipulators used for precision freefield measurements including nearfield acoustic holography and compact range scattering. The precision robotics, environmental control, and painstaking measures to insure homogeneity and stability result in a high fidelity, versatile, and unique underwater acoustic measurement laboratory. The LSA also contains an indoor rectangular tank (10m by 8m) laboratory, with a 3m deep sand bottom and 4m of water column. In a similar fashion to the freefield laboratory, this laboratory is used to study target scattering in a marine bottom environment. We discuss such databases focused on the challenging problem of unexploded ordinance (UXO) in water where we use the structural acoustic response measured in a series of laboratory experiments to detect and identify several common UXOs. The 360 degree broadband (1‐140 kHz) compact range monostatic and bistatic measurements taken in both laboratories will be discussed.

One- and two-dimensional single-mode differential fiber-optic displacement sensor for submillimeter measurements

Using the overlap integral method and the Gaussian approximation for the single-mode fiber-optic field, the working principle of one- and two-dimensional differential fiber-optic displacement sensors for submillimeter measurements is demonstrated. The sensors consist of one emitting fiber and two or three receiving fibers, respectively, for the one- and two-dimensional sensors. Sensor responses are intrinsically linear over a wide range of travels. Moreover, for the two-dimensional sensor, each axis of displacement can be measured independently. Sensor responses are simulated experimentally using a highly precise robot. Linearity, travel, and sensitivity are characterized for the different gap distance between the emitting and receiving fibers. A design chart that includes nonlinearity error, travel, sensitivity, and gap is finally proposed.

AN IMAGE-GUIDED MAGNETIC RESONANCE-COMPATIBLE SURGICAL ROBOT

The past decade has witnessed the increasing application of robotics in surgery, yet there is no existing system that combines stereotaxy and microsurgery in an imaging environment. To fulfill this niche, we have designed and manufactured an image-guided robotic system that is compatible with magnetic resonance imaging. The system conveys the sight, touch, and sound of surgery to an operator seated at a remote workstation. Motion scaling, tremor filtering, and precision robotics allow surgeons to rapidly attain technical proficiency while working at a spatial resolution of 50 to 100 microm instead of a few millimeters. This system has the potential to shift surgery from the organ toward the cellular level. By integrating the robot with images obtained during the procedure, the effects of surgery on both the lesion and brain are immediately revealed. We are providing technology to advance and transform surgery with the potential to improve patient outcome.

Survey on parallel manipulators with micro/nano manipulation technology and applications

Micro/nano manipulation is a new research direction of parallel manipulator along with the development of nanotechnology,which covers precision machinery,robotics,computer technology,automatic control,and precise measurement,etc., and has been widely used in cells or gene manipulation in biomedical field,precise surgery,microelectronic assembly, micromachining,fiber alignment,etc.The most recent work on micromanipulator research,related industrial products and applications are surveyed,then some problems existing in workspace,movement decoupling,bearing capacity,theoretical analysis, flexure hinge design,real-time calibration and measurement,new materials and actuators,etc.,are pointed out and some improvements are proposed.The research will be helpful to future creative design and research development.

A precision robot system with modular actuators and MEMS micro gripper for micro system assembly

A robotic system which consists of a precision manipulator and a micro gripper for a micro system assembly is presented. The developed P-R-R type 3 DOF robot is actuated by newly proposed modular revolute and prismatic actuators. As an end-effector of this manipulator, a micro gripper is designed and fabricated with MEMS technology, and the displacement of the jaw is up to 142.8 μm. A real gripping test is conducted to evaluate the robotic system.

Matched Feedforward/Model Reference Control of a High Precision Robot With Dead-Zone

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> A matched feedforward/model reference control is proposed in this brief to improve the transient characteristics of systems with uncertain parasitic nonlinearities. In particular, attention is focused on a New England Affiliated Technologies (NEAT) four-axis positioning system which is designed for high-precision applications. Due to the presence of a dead-zone with variable boundaries in this robot, most conventional methods tend to produce unacceptable transients or steady-state errors. The proposed control method is analyzed for its properties and subsequently implemented on the NEAT robot for experimental verifications. It is observed that the matched feedforward/model reference control method is effective while robust to plant and dead-zone boundary uncertainties. </para>

A SELF-TUNING TORQUE FEEDBACK FOR CONTROL OF MANIPULATORS

Joint-torque sensory feedback (JTF) can achieve precise robot control through a relatively simple control implementation, if accurate measurements of joint torques are available. This paper presents the development of an adaptive JTF control law that requires only the incorporation of uncalibrated joint torque signals, i.e., the gains and offsets of the torque sensors are unknown. Also, all physical parameters of the joints including the inertia of the rotors, link twist angles, and friction parameters are assumed unknowns to the controller. The robot dynamics with JTF is presented in a standard form with minimum number of parameters, where the inertia matrix appears symmetric and positive definite. Simulation and experimental results are presented to demonstrate disturbance rejection and tracking performance of the proposed adaptive JTF controller.

Precision robot welding for world's largest particle physics apparatus

Precision robot welding for world's largest particle physics apparatus

Precision robot welding for world's largest particle physics apparatus

Precision robot welding for world's largest particle physics apparatus

Gene expression profiling and its application in studies of haematological malignancy.

Gene expression profiling and its application in studies of haematological malignancy.

The position/Orientation determination of a mobile-task robot using an active calibration scheme

A new method of estimating the pose of a mobile-task robot is developed based upon an active calibration scheme. The utility of a mobile-task robot is widely recognized, which is formed by the serial connection of a mobile robot and a task robot. To be an efficient and precise mobile-task robot, the control uncertainties in the mobile robot should be resolved. Unless the mobile robot provides an accurate and stable base, the task robot cannot perform various tasks. For the control of the mobile robot, an absolute position sensor is necessary. However, on account of rolling and slippage of wheels on the ground, there does not exist any reliable position sensor for the mobile robot. This paper proposes an active calibration scheme to estimate the pose of a mobile robot that carries a task robot on the top. The active calibration scheme is to estimate a pose of the mobile robot using the relative position/orientation to a known object whose location, size, and shape are known a priori. For this calibration, a camera is attached on the top of the task robot to capture the images of the objects. These images are used to estimate the pose of the camera itself with respect to the known objects. Through the homogeneous transformation, the absolute position/orientation of the camera is calculated and propagated to get the pose of a mobile robot. Two types of objects are used here as samples of work-pieces : a polygonal and a cylindrical object. With these two samples, the proposed active calibration scheme is verified experimentally.

Robot-assisted Navigated Neuroendoscopy

Major steps in the evolution of advanced neurosurgical techniques include microneurosurgery, neuroendoscopy and its minimally invasive variations, neuronavigation, and advanced intraoperative imaging. With traditional neuroendoscopic techniques (e.g., freehand endoscopy or the use of mechanical arms), definitive controlled movement of the endoscope within the brain depends on the experience and skill of the individual neurosurgeon. With the Evolution 1 precision robot (Universal Robot Systems, Schwerin, Germany), a new neurosurgical tool has become available for the precise steering of instruments within the cranium. After preclinical anatomic and precision studies, the system was used for neuronavigated endoscopic procedures for three patients. All robot-assisted, navigated, endoscopic procedures were successfully completed. The time for the registration procedure and setup of the robot decreased from 60 minutes for the first patient to 30 minutes for the third patient. The time for the surgical part of the endoscopic procedure ranged from 17 to 65 minutes. No complications occurred during any procedure. The use of robotic technology for neuroendoscopic procedures is a major advance for controlled movement of the endoscope within the cranium. The start-up procedure and calibration of the robot are still time-consuming, but the actual operation time is comparable to that of freehand neuroendoscopic procedures. Steering of the endoscope is facilitated, and the precision of the endoscopic movements is noteworthy.