Hardware Experiments of Autonomous Space Robot – A Demonstration of Truss Structure Assembly –

2000 ◽  
Vol 12 (4) ◽  
pp. 343-350 ◽  
Author(s):  
Kei Senda ◽  
◽  
Yoshisada Murotsu ◽  
Akira Mitsuya ◽  
Hirokazu Adachi ◽  
...  
Keyword(s):  
Experimental System ◽  
Space Robot ◽  
Truss Structure ◽  
Two Dimensional ◽  
Air Bearings ◽  
Vision Sensor ◽  
Space Robots ◽  
Automatic Construction ◽  
System A ◽  
Structure Assembly

This paper addresses an experimental system simulating a free-flying space robot, which has been constructed to study autonomous space robots. The experimental system consists of a space robot model, a frictionless table system, a computer system, and a vision sensor system. The robot model composed of two manipulators and a satellite vehicle can move freely on a two-dimensional planar table without friction by using air-bearings. The robot model has successfully performed the automatic truss structure construction including many jobs, e.g., manipulator berthing, component manipulation, arm trajectory control avoiding collision, assembly considering contact with the environment, etc. The experiment demonstrates the possibility of the automatic construction and the usefulness of space robots.

Antifibrinolytic Action of the Anticoagulant Split Product of Fibrinogen

1968 ◽  
Vol 19 (03/04) ◽  
pp. 526-532 ◽  
Author(s):  
L. B Nanninga ◽  
M. M Guest
Keyword(s):  
Experimental System ◽  
New Method ◽  
System A ◽  
Fibrinogenolytic Activity

SummaryThe purified anticoagulant split product of fibrinogen has antifibrinolytic and anti-fibrinogenolytic activity. This was investigated by lysis times of fibrin and by the rate of disappearance of fibrinogen in plasma and in a purified system. A new method was used to measure fibrinogenolytic activity. In the experimental system which we have used no indication of additional breakdown of the anticoagulant split product in the presence of fibrinolysin was obtained.

New Methods for Analyzing Water Pollutants

1982 ◽  
Vol 14 (4-5) ◽  
pp. 59-71 ◽  
Author(s):  
L H Keith ◽  
R C Hall ◽  
R C Hanisch ◽  
R G Landolt ◽  
J E Henderson
Keyword(s):  
Amino Acids ◽  
Gas Chromatography ◽  
Two Dimensional ◽  
Gas Chromatograph ◽  
New Class ◽  
New Methods ◽  
System A ◽  
Drinking Waters ◽  
Computer Controlled ◽  
Nitrogen Containing Compounds

Two new methods have been developed to analyze for organic pollutants in water. The first, two-dimensional gas chromatography, using post detector peak recycling (PDPR), involves the use of a computer-controlled gas Chromatograph to selectively trap compounds of interest and rechromatograph them on a second column, recycling them through the same detector again. The second employs a new detector system, a thermally modulated electron capture detector (TMECD). Both methods were used to demonstrate their utility by applying them to the analysis of a new class of potentially ubiquitous anthropoaqueous pollutants in drinking waters- -haloacetonitriles. These newly identified compounds are produced from certain amino acids and other nitrogen-containing compounds reacting with chlorine during the disinfection stage of treatment.

scholarly journals Sampling-Based Motion Planning for Free-Floating Space Robot without Inverse Kinematics

2020 ◽  
Vol 10 (24) ◽  
pp. 9137
Author(s):  
Hongwen Zhang ◽  
Zhanxia Zhu
Keyword(s):  
Motion Planning ◽  
Inverse Kinematics ◽  
Random Trees ◽  
Space Robot ◽  
Initial Configuration ◽  
First Order ◽  
System A ◽  
Planning Framework ◽  
Planning Algorithm ◽  
Differential Relationship

Motion planning is one of the most important technologies for free-floating space robots (FFSRs) to increase operation safety and autonomy in orbit. As a nonholonomic system, a first-order differential relationship exists between the joint angle and the base attitude of the space robot, which makes it pretty challenging to implement the relevant motion planning. Meanwhile, the existing planning framework must solve inverse kinematics for goal configuration and has the limitation that the goal configuration and the initial configuration may not be in the same connected domain. Thus, faced with these questions, this paper investigates a novel motion planning algorithm based on rapidly-exploring random trees (RRTs) for an FFSR from an initial configuration to a goal end-effector (EE) pose. In a motion planning algorithm designed to deal with differential constraints and restrict base attitude disturbance, two control-based local planners are proposed, respectively, for random configuration guiding growth and goal EE pose-guiding growth of the tree. The former can ensure the effective exploration of the configuration space, and the latter can reduce the possibility of occurrence of singularity while ensuring the fast convergence of the algorithm and no violation of the attitude constraints. Compared with the existing works, it does not require the inverse kinematics to be solved while the planning task is completed and the attitude constraint is preserved. The simulation results verify the effectiveness of the algorithm.

scholarly journals Flexible Rope Manipulation Using Elastic Deformation Modeling by Dual Manipulator System with Vision Sensor

2004 ◽  
Vol 16 (1) ◽  
pp. 31-38 ◽  
Author(s):  
Takayuki Matsuno ◽  
◽  
Toshio Fukuda ◽  
Fumihito Arai ◽  
Yasuhisa Hasegawa ◽  
...  
Keyword(s):  
Object Recognition ◽  
Elastic Deformation ◽  
Object Manipulation ◽  
Object Model ◽  
Vision Sensor ◽  
Recognition Method ◽  
Simple Task ◽  
System A

In this paper we propose a flexible object manipulation method by a dual manipulator system. A flexible object such a rope and paper is easily deformed and has hysteresis. Various approaches have been made on the research for the flexible object manipulation. However in the former research works, the manipulator system works only simple task. For more complex works with flexible object, the robot has to hand over the flexible object. So, we propose a flexible object recognition method which can hand over a flexible object using vision information and flexible object model. The dual manipulator system tied a cylinder object with flexible rope by repeating handing over actions in the experiment.

scholarly journals Development of integrated multi-trophic aquaculture (IMTA) for tropical brackishwater species in Sindhudurg District, Maharashtra, west coast of India

2018 ◽  
Vol 65 (1) ◽  
Author(s):  
C. P. Balasubramanian ◽  
Shailesh S. Mhaskar ◽  
Krishna Sukumaran ◽  
A. Panigrahi ◽  
Kurmaraguru Vasagam ◽  
...  
Keyword(s):  
Experimental System ◽  
Open Water ◽  
Trophic Levels ◽  
Cost Ratio ◽  
Benefit Cost Ratio ◽  
System A ◽  
Etroplus Suratensis ◽  
Penaeus Indicus ◽  
Benefit Cost ◽  
And Control

Integrated multi-trophic aquaculture (IMTA), farming of species from different trophic levels and with complimentary ecosystem function, is regarded as a suitable approach to develop a sustainable aquaculture system. In order to establish an IMTA system, a study was carried out in Sindhudurg District, Maharashtra, India for selected tropical brackish-water species. Two equal sized pens (250 m2) were constructed for IMTA and control respectively in each land based system and open water cages were set in the estuary. Different combinations of fed species (Chanos chanos, Etroplus suratensis, Mugil cephalus, Penaeus indicus) and an extractive crop (Crassostrea madrasensis) were stocked in IMTA experimental system whereas monoculture of P. indicus served as control. Water quality characteristics were found to be within the admissible limits. Soil organic carbon was found to be lesser in the IMTA system compared to control. The productivity of IMTA system was higher than control: 3250 kg h-1 vs 2000 kg ha-1. Further, income and benefit-cost ratio was found to be higher in IMTA pens. The present study concludes that IMTA is a possible option for system diversification as well as species diversification without compromising economic profitability of culture.

Inverse Dynamics Algorithm for Space Robots

1996 ◽  
Vol 118 (3) ◽  
pp. 625-629 ◽  
Author(s):  
Subir Kumar Saha
Keyword(s):  
Efficient Algorithm ◽  
Dynamic Models ◽  
Inverse Dynamics ◽  
Recursive Algorithm ◽  
Space Robot ◽  
Orthogonal Complement ◽  
Free Base ◽  
Space Robots ◽  
Primary Body ◽  
Kinematic Models

An efficient algorithm for the inverse dynamics of free-flying space robots, consisting of a serial manipulator mounted on a free-base, e.g., a spacecraft, is presented. The kinematic and dynamic models are based on the concepts of the Primary Body (PB) and the Natural Orthogonal Complement, respectively, reported elsewhere. In this paper, besides the efficiency, the usefulness of the PB in deriving different kinematic models and selecting an efficient one is pointed out. Moreover, it is shown that a recursive algorithm for the inverse dynamics of the space robot at hand can be developed even without the consideration of the momenta conservation principle.

The Asymptotic Stability of Weakly Perturbed Two Dimensional Hamiltonian Systems

2001 ◽  
Author(s):  
Ludwig Arnold ◽  
Peter Imkeller ◽  
N. Sri Namachchivaya
Keyword(s):  
Lyapunov Exponent ◽  
Equations Of Motion ◽  
Perturbation Approach ◽  
Two Dimensional ◽  
White Noise Process ◽  
System A ◽  
Additive White Noise ◽  
Small Dissipation ◽  
Small Intensity ◽  
Single Well

Abstract The purpose of this work is to obtain an approximation for the top Lyapunov exponent, the exponential growth rate, of the response of a single-well Kramers Oscillator driven by either a multiplicative or an additive white noise process. To this end, we consider the equations of motion as dissipative and noisy perturbations of a two-dimensional Hamiltonian system. A perturbation approach is used to obtain explicit expressions for the exponent in the presence of small intensity noise and small dissipation. We show analytically that the top Lyapunov exponent is positive, and for small values of noise intensity ε and dissipation ε the exponent grows proportional to ε1/3.

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