Robotic location of underground chemical sources

Robotica ◽  
2004 ◽  
Vol 22 (1) ◽  
pp. 109-115 ◽  
Author(s):  
R. Andrew Russell
Keyword(s):  
Robot Manipulator ◽  
Search Algorithm ◽  
Chemical Vapour ◽  
Coarse Sand ◽  
Land Mines ◽  
Factors Affecting ◽  
Sensory Environment ◽  
Manipulator Arm ◽  
Unexploded Ordinance ◽  
Sensor Probe

This paper describes current progress in a project to develop robotic systems for locating underground chemical sources. There are a number of economic and humanitarian applications for this technology. Finding unexploded ordinance, land mines, and sources of leaks from pipes and tanks are some examples. Initial experiments were conducted using an ethanol chemical source buried in coarse sand. To gain an understanding of the sensory environment that would be experienced by a robot burrowing through the ground, the factors affecting transport of chemical vapour through soil were investigated. A robot search algorithrn was then developed for gathering chemical gradient inforrnation and using this to guide a robot towards the source. Experiments were performed using a chemical sensing probe positioned by a UMI RTX robot manipulator arm. The resulting system was successful in locating a source of ethanol vapour buried in sand. This paper includes details of experiments to characterise the sand used in this project, the robot search algorithm, sensor probe and results of source location trials.

Manipulator system designs for drawing random objects through point cloud posture estimation

2021 ◽  
pp. 095440542097946
Author(s):  
Ching-Chang Wong ◽  
Hsuan Ming Feng ◽  
Yu-Cheng Lai ◽  
Hsiang-Yun Chen
Keyword(s):  
Point Cloud ◽  
Null Space ◽  
Robot Manipulator ◽  
Search Algorithm ◽  
Movement Control ◽  
Control Policy ◽  
Device Management ◽  
Redundant Robot ◽  
Better Regulation ◽  
The Right

This paper designed a 7-DOF redundant robot manipulator that can flexibly and efficiently pick-up random objects. The developed 7-DOF machine with an additional redundancy achieved great progress in terms of flexibility and efficiency in the operational space. A robot operating system (ROS) was used to configure the manipulator system’s software modules, supporting convenient system interface, appropriate movement control policy, and powerful hardware device management for better regulation of the manipulator’s motions. A 3D type Point Cloud Library (PCL) was utilized to perform a novel point cloud image pre-processing method that did not only reduce the point cloud number but also maintained the original quality. The results of the experiment showed that the estimation speed in object detection and recognition procedure improved significantly. The redundant robot manipulator architecture with the two-stage search algorithm was able to find the optimal null space. Suitable parameters in D-H transformation of forward kinematics were selected to efficiently control and position the manipulator in the right posture. Meanwhile, the reverse kinematics estimated all angles of the joints through the known manipulator position, orientation, and redundancy. Finally, motion panning implementation of manipulator rapidly and successfully reached the random object position and automatically drew it up to approximate the desired target.

Conditions of Parametric Resonance in Periodically Time-Variant Systems With Distributed Parameters

2009 ◽  
Vol 131 (3) ◽  
Author(s):  
Yong-Kwan Lee ◽  
Leonid S. Chechurin
Keyword(s):  
Parametric Resonance ◽  
Robot Manipulator ◽  
Synchronous Generator ◽  
Constant Current ◽  
Time Varying ◽  
Distributed Parameters ◽  
Time Varying Parameter ◽  
Manipulator Arm ◽  
The Stability ◽  
Systems With Distributed Parameters

Theoretical analysis of the stability problem for the control systems with distributed parameters shall be given. The approach to the analysis of such systems can be composed of two parts. First, the distributed parameter element is modeled by a frequency response function. Second, approximate conditions of parametric resonance are derived by a method of stationarization (describing functions of time-variant elements). The approach is illustrated by two examples. One is a robot-manipulator arm (distributed mechanical parameter system) controlled by a controller with a modulator/demodulator cascade (time-varying element). Another is an electromechanical transformer that consists of a constant current motor and a synchronous generator. Inductance between stator windings and the rotor of the synchronous generator serves as a periodical time-varying parameter, and a long electrical line plays the role of an element with distributed parameters. In both examples, dangerous (in terms of the first parametric resonance) regions for time-varying parameter are obtained theoretically and compared with simulation experiment.

A Frequency Domain Identification Scheme for Control and Fault Diagnosis

1997 ◽  
Vol 119 (1) ◽  
pp. 48-56 ◽  
Author(s):  
G. Mallory ◽  
R. Doraiswami
Keyword(s):  
Frequency Domain ◽  
Linear Time ◽  
Robot Manipulator ◽  
Physical Parameters ◽  
Linear Time Invariant ◽  
Domain Identification ◽  
Frequency Domain Identification ◽  
Identification Technique ◽  
Manipulator Arm ◽  
Linear Time Invariant System

A robust scheme to estimate a set of models for a linear time-invariant system, subject to perturbations in the physical parameters, from a frequency response data record is proposed. The true model as well as the disturbances affecting the system are assumed unknown. However, the physical parameters are assumed to enter the coefficients of the system transfer function multilinearly. A set of models is identified by perturbing the physical parameters one-at-time and using a frequency domain identification technique. Exploiting the assumed multilinearity, the estimated set of models is validated. The proposed scheme is evaluated on a number of simulated systems, and on a physical robot manipulator arm.

Sulfonylurea herbicides applied to acidic sandy soils: a bioassay for residues and factors affecting recoveries

1991 ◽  
Vol 42 (7) ◽  
pp. 1205 ◽  
Author(s):  
WM Blacklow ◽  
WM Blacklow ◽  
PC Pheloung ◽  
PC Pheloung
Keyword(s):  
Half Life ◽  
Lens Culinaris ◽  
Sandy Loam ◽  
Crop Protection ◽  
Coarse Sand ◽  
Cereal Crop ◽  
Minimum Concentration ◽  
Factors Affecting ◽  
White Sand ◽  
Plastic Bags

Chlorsulfuron and triasulfuron, applied at 15-35 g ha-1, are a challenge to analytical methods because residues are phytotoxic at concentrations of pg kg-1 soil. A bioassay based on the suppression of root growth of lentils (Lens culinaris cv. Laird) can detect a minimum concentration of 0.48g kg-1 soil. The sandy loam, 20g, is extracted with methanol and extracts are made up in 5 mM CaCl2. The extracts, 20 mL, are added to 250 g of coarse white sand in plastic cups and sown with seven pre-germinated lentil seeds. The cups are enclosed in plastic bags to prevent evaporation, and incubated for 6 days at 20�C. Herbicide concentrations are brought within the range of sensitivity of the bioassay by dilutions of the extracts. The assay was easier, and more sensitive, precise and reproducible than a direct assay of soil. Herbicides in the field were lost due to photolysis (38-49% in 8 h) and in laboratory manipulations by hydrolysis with high pH extractants, such as saturated Ca(OH)2 (pH 11.2) where the half-life was about 4 h. Hydrolysis at the pH of the sandy loam and the bioassay in coarse sand, pH 5 - 8, gave a half-life of 176 and 198 days for chlorsulfuron and triasulfuron, respectively, at 20�C; at 30�C, the corresponding half-lives were 47 and 27 days. At concentrations for 50% suppressions of lentil roots (ID50 = 0.6 8g L-1 in coarsesand), adsorption in the sandy loam, estimated by the Langmuir equation, was 76% of the total residues of both herbicides. Adsorption could account for the differences in the ID50 of lentils grown in sandy loam and coarse sand for triasulfuron, but it was overcorrected for chlorsulfuron. The herbicides should be applied as near to seeding the cereal crop as possible and should be incorporated with the seeding operation so that losses from photolysis and hydrolysis in warm acidic soils are minimized before crop protection is needed.

scholarly journals Electronic Architecture for a Mobile Manipulator

2018 ◽  
Vol 14 (02) ◽  
pp. 133
Author(s):  
Oscar Aviles ◽  
Mauricio Felipe Mauledoux Monroy ◽  
Oscar Rubiano
Keyword(s):  
Mobile Robot ◽  
Degrees Of Freedom ◽  
Robot Manipulator ◽  
Robotic System ◽  
Mobile Platform ◽  
Mobile Manipulator ◽  
Human Being ◽  
Manipulator Arm ◽  
Electronic Design

A mobile manipulator is a robotic system consisting of a mobile platform on which a manipulator arm is mounted, allowing the robotic system to perform locomotion and manipulation tasks simultaneously. A mobile manipulator has several advantages over a robot manipulator which is fixed, the main advantage is a larger workspace. The robots manipulators are oriented to work collaboratively with the human being in tasks that simultaneously require mobility and ability to interact with the environment through the manipulation of objects. This article will present the electronic design for a mobile robot manipulator with five degrees of freedom and a 6-wheel traction with four of these directional.

Quantitative Investigation of the Factors Affecting the Hydrothermal Growth of Zinc Oxide Nanowires

2009 ◽  
Vol 1174 ◽  
Author(s):  
Aron Robert Rachamim ◽  
Sharvari H. Dalal ◽  
Sieglinde M.-L. Pfaendler ◽  
Michael E. Swanwick ◽  
Andrew Flewitt ◽  
...  
Keyword(s):  
Growth Rate ◽  
Zinc Oxide ◽  
Chemical Vapour ◽  
Average Diameter ◽  
Zinc Nitrate ◽  
Hydrothermal Growth ◽  
Factors Affecting ◽  
Oxide Nanowires ◽  
Device Applications ◽  
Axial Growth

AbstractZinc oxide (ZnO) nanowires (NWs) are receiving significant industrial and academic attention for a variety of novel electronic, optoelectronic and MEMS device applications due to their unusual combination of physical properties, including being optically transparent, semiconducting and piezoelectric. Hydrothermal growth is possible at significantly lower temperatures (and hence lower thermal budgets) compared with other NW growth methods, such as chemical vapour deposition. In this context, the hydrothermal growth of ZnO NWs on seeded substrates immersed in equimolar zinc nitrate/HMTA aqueous solution was investigated. NWs were grown on polished silicon (001) substrates, and the solution concentrations, temperatures and growth times were varied. Importantly, the NW diameter was found to depend only on concentration during hydrothermal growth for times up to 4 hours. The average diameter was 14 nm in 0.005 M solution and increased up to a maximum 150 nm at 0.07 M, when the NWs formed a continuous polycrystalline film. Concentration and temperature were all found to affect the axial growth rate of NWs in the [0001] direction. The growth rate was constant up to 4 hours (200 nm hr-1) for constant conditions (81 oC, 0.025 M). The growth rate was found to increase approximately linearly with concentration at a rate of 7840 nm M-1 hr-1 up to 0.06 M (81 oC solution). The growth rate also increased linearly with temperature at a rate of 4.9 nm hr-1 K-1 (0.025 M solution). This indicates that growth takes place close to the equilibrium point, found by linear regression to be 36 oC for 0.025 M solution.

Self-tuning control of a robot manipulator arm

1989 ◽  
Vol 27 (3) ◽  
pp. 423-449
Author(s):  
W. WAHABT ◽  
P. E. WELLSTEAD
Keyword(s):  
Robot Manipulator ◽  
Manipulator Arm ◽  
Self Tuning

scholarly journals Host Range, Biology, and Factors Affecting Survival and Reproduction of the Stubby Root Nematode

1969 ◽  
Vol 54 ◽  
pp. 341-369
Author(s):  
Alejandro Ayala ◽  
M. W. Allen ◽  
E. M. Noffsinger
Keyword(s):  
Plant Species ◽  
Nutrient Solution ◽  
Tobacco Rattle Virus ◽  
Ecological Factors ◽  
Nematode Species ◽  
Coarse Sand ◽  
Nematode Reproduction ◽  
Factors Affecting ◽  
Survival And Reproduction ◽  
Stubby Root Nematode

Populations of T. allius increased to levels nine times higher in Glurk tobacco plants infected with California tobacco rattle virus than in healthy plants of the same variety and age. Populations of T. christiei increased with applications of Hoagland's nutrient solution diluted up to 50-percent concentration, whereas population densities were low at the highest concentration (100 percent), and in water alone. Trichodorus allius did not seem to be affected to a large extent by similar applications of Hoagland's nutrient solution. Soil type influenced populations of T. allius; lighter soils were conducive to development of higher populations while soil, coarse sand, and white quartz sand used separately were not favorable for reproduction. Temperature proved to be one of the most important ecological factors in nematode reproduction. The optimum temperatures for the reproduction of each species was as follows: T. christiei, 16° to 24° C; T. porosus, 24° C; and. T allius, 21° to 24° C. Extremes of temperatures at which the different species could reproduce also varied. Populations of T. christiei were affected by an undetermined disease or condition which seemed to slow movement but did not have any apparent effect on rate of reproduction. Host ranges of three species of Trichodorus were studied. All three nematode species seemed to be polyphagous because 90 percent, 90 percent and 95 percent of the plant species tested were hosts of T. christiei, T. porosus, and T. allius, respectively. Twenty-five plant species were tested for T. porosus, 50 for T. christiei and 38 for T. allius. A method is described for keeping populations of T. allius alive in water for extended periods of time.

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