The increasing use of computer controlled mobile robots in various tasks has created a growing technological need for efficient low cost means and methods for mobile robot guidance. This work presents a robot navigati...
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ISBN:
(纸本)0819429783
The increasing use of computer controlled mobile robots in various tasks has created a growing technological need for efficient low cost means and methods for mobile robot guidance. This work presents a robot navigation and guidance system that consists of a directional light sensor and a set of at least three uniquely coded light sources, The three light sources provide distinct light fields in the operating area of the robot. The light sensor, mounted on a mobile robot, is used to measure the angle of the direction of origin of each of the three light: sources with respect to the robot reference frame. The local room coordinates of the robot can then be determined by an on-board microprocessor system. The planar position and orientation of the robot can be used to control the drive and steering mechanisms to reach a given target position or track a prescribed trajectory. Control methods for robot guidance are discussed.
Perspective flightpath displays and the depiction of 3-D terrain are regarded as a potential means to increase safety. Although the technology to generate such presentations in real-time is available, other issues whi...
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ISBN:
(纸本)0819428132
Perspective flightpath displays and the depiction of 3-D terrain are regarded as a potential means to increase safety. Although the technology to generate such presentations in real-time is available, other issues which are required for a safe introduction must still be resolved. This paper focuses on some of the major obstacles which are still present. It discusses several objections against perspective flightpath displays and shows why most of them are no longer justified. The potential for an increase in safety is related to navigation, guidance, and control task requirements, and potential implementations, ranging in complexity, to satisfy these requirements are discussed. This classification allows a gradual transition from today's 2-D symbolic displays to future spatial displays. The paper proposes an approach which supports an evolutionary introduction of 3-D navigation displays into the cockpit.
Glass surfaces were patterned with cell-adhesive regions of laminin adhesive peptides YIGSR, RGD, and IKVAV, and cell-repulsive regions of poly(ethylene glycol) (PEG). The patterns were created by sputter-coating tita...
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Glass surfaces were patterned with cell-adhesive regions of laminin adhesive peptides YIGSR, RGD, and IKVAV, and cell-repulsive regions of poly(ethylene glycol) (PEG). The patterns were created by sputter-coating titanium and then gold onto glass coverslips through electron microscope grids. Gold surfaces were modified with cysteine-terminated peptides to have approximately 450 fmol/cm(2) of peptide incorporated on the glass coverslips as determined with radiolabeled CGYIGSR. Amine-functionalized glass coverslips were prepared using an amine-functionalized silane and then further modified with PEG-aldehyde by a Schiff base reduction. All surfaces were characterized by X-ray photoelectron spectroscopy and water contact angles. Hippocampal neurons, plated from a serum-free medium, adhered preferentially to peptide-functionalized surfaces over PEG-modified surfaces. Cell adhesion and neurite outgrowth were limited to the peptide region, demonstrating that neurite outgrowth could be directed by a combination of cell-adhesive and cell-repulsive cues. (C) 1998 John Wiley & Sons, Inc.
Polar satellite launch vehicle PSLV is an optimally guided and controlled vehicle that has several fault tolerant and in flight retargetting features. Several flights have proven the soundness of control and guidance ...
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Polar satellite launch vehicle PSLV is an optimally guided and controlled vehicle that has several fault tolerant and in flight retargetting features. Several flights have proven the soundness of control and guidance design. Features of Control & guidance system of PSLV are described.
The method of the air-combat evaluation only by computer simulations is presented The mathematical models of the vehicles; aircraft, missile and bullet, their dynamics and guidance and control system are explained As ...
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The method of the air-combat evaluation only by computer simulations is presented The mathematical models of the vehicles; aircraft, missile and bullet, their dynamics and guidance and control system are explained As the preciseness of simulation models depends on the purpose of evaluation, the difference between the six cEgrees-of-freedom rigid body model and the point mass model, the analytical function model is explained Some tactics of the aircraft in air-combat are also explained and combat simulation examples are shown.
During the guidance process of an antiradiation missile (ARM), the target radar is often switched off in order to avoid being attacked. This will cause the passive seeker in ARM disabled, so the guidance system of the...
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During the guidance process of an antiradiation missile (ARM), the target radar is often switched off in order to avoid being attacked. This will cause the passive seeker in ARM disabled, so the guidance system of the missile will stop working. To solve this problem, a scheme called LOS angles optimal estimation, has been put forward,based on the fault-tolerant design method of system reconstruction. The effectiveness of the proposed scheme has been proved by the simulations.
This paper addresses the problem of designing guidance, control and navigation systems for autonomous underwater vehicles (AUVs). Its contribution is twofold: i) it introduces a new methodology for the integrated desi...
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This paper addresses the problem of designing guidance, control and navigation systems for autonomous underwater vehicles (AUVs). Its contribution is twofold: i) it introduces a new methodology for the integrated design of guidance and control, and ii) it describes a novel approach to the analysis and design of multi-rate complementary filters for navigation. The methodologies proposed lead to an efficient procedure for the design of controllers for AUVs, to accurately track reference trajectories defined in an inertial reference frame. The paper illustrates the application of that procedure to the design of a tracking controller for the MARIUS AUV. The design phase is summarized, and the performance of the resulting controller is assessed in simulations, using dynamic models of the vehicle and its sensor suite.
In order to assist the people in the transportation industry in accurately understanding and interpreting the transportation regulations, a prototype expert guidance system called REGS has been developed for Part 382 ...
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In order to assist the people in the transportation industry in accurately understanding and interpreting the transportation regulations, a prototype expert guidance system called REGS has been developed for Part 382 of the Federal Motor Carrier Safety Regulations. This PC-based system models the regulatory guidance methodology employed by statutory interpretation experts in the industry. The working environment of this system is very user-friendly. When a query is put forth requesting interpretation, the system is initiated and the user is presented with a set of choices. These choices are designed to cater to the needs of the user for providing appropriate and adequate guidance. If the user chooses to run the REGS module, the system puts forth a series of questions to arrive at the conclusions. While the user responds to these questions, the system evaluates the responses, internally reviews the relevant regulations and past interpretations and stops to provide a conclusion. The system can also handle "how", "why" and "what-if' type of questions by giving explicit explanations. While the system searches through its regulations knowledge base, the user is provided an option to look at the regulatory text, select the relevant sections and print them if it is required to answer the request for interpretation. This type of "all at one place" guidance helps the user to understand the intent latent in the regulations. It also helps the user in assembling a boilerplate response based on which an interpretation for the request can be prepared. The system is useful to enforcement officials, motor carrier company officials, drivers and government regulators, who all need to be intimately familiar with Part 382 of the FMCSRs. Since the architecture of REGS is transportable to any set of regulations, similar systems could easily be developed for any other set of transportation regulations.
Additional guidance has been published on the third edition of the Civil Engineering Standard Method of Measurement. John Banyard, chairman of ICE's standing CESSM review committee, explains.
Additional guidance has been published on the third edition of the Civil Engineering Standard Method of Measurement. John Banyard, chairman of ICE's standing CESSM review committee, explains.
This paper describes a solution to the problem of 3-D trajectory tracking for Autonomous Underwater Vehicles (AUVs). The trajectories considered consist of segments of trimming helices, which are parameterized by the ...
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This paper describes a solution to the problem of 3-D trajectory tracking for Autonomous Underwater Vehicles (AUVs). The trajectories considered consist of segments of trimming helices, which are parameterized by the vehicle's linear speed, yaw rate and flight path angle. Motivated by recent developments in robotics, the linear position of an AUV is given in terms of its location with respect to the closest point on a desired trajectory, together with the length of an imaginary curve traced along that trajectory. Tracking of a trimming trajectory by the vehicle at a fixed speed is then converted into the problem of driving a generalized error vector - that implicitly includes the distance to the trajectory - to zero. By showing that the linearization of the generalized error dynamics about trimming trajectories is time-invariant, the problem of trajectory tracking is posed and solved in the framework of gain scheduled control theory. This leads to a new method for the integrated design of guidance and control systems for AUVs.
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