Modeling and Analyses of the N-link PenduBot
As the foundation of the multi-link PenduBot control, the mathematical model should be established first. Based on the method of kinematics and dynamics, the N-link PenduBot mathematical models are established in this paper, including the nonlinear model, the linear model and the generalized model which considers the motor characteristic. The natural characteristic of the system is analyzed. By using the condition number of the controllability matrix, the control difficulty for the higher order systems is compared. From the comparison result, the control law of the different links PenduBot is obtained. Increasing with the count of PenduBot links, the control difficulty is growing dramatically. Only a strong control measure can make it stable. So, further study on multi-link PenduBot can be carried on.
Research on Control Problem of PenduBot Based on PSO Algorithm
PenduBot is a new experiment object in the control theory and a typical representation in the underactuated robot, so it is the research focus of control and robot domain. It is known for its strongly nonlinear and naturally unstable properties. To stabilize the PenduBot and verify the control abilities of the algorithm on strongly nonlinear and naturally unstable properties, the thesis presents the purpose that the state-feedback matrixes can be optimized by new bionics algorithm PSO. Based on the introduction of standard PSO algorithm, how to select the position and velocity evolution equations parameters and fitness function became a great emphasis. Next, the simulations were done on the linearized PenduBot model in MATLAB environment by PSO and LQR algorithm separately, and the results were compared. Finally, the comparison results proved the PSO advantages. The expected goal was achieved.
Intentional poisoning cases of animals with anticholinesterase pesticide-carbofuran in Sri Lanka.
Carbofuran is a broad spectrum insecticide and nematicide which inhibits acetyl cholinesterase. Several intentional poisoning cases of animals and birds including crows, dogs, cow, and elephant, using carbofuran were reported in Sri Lanka. Qualitative analysis of carbofuran in biological specimens was carried out using T.L.C and GC-MS. The quantitative analysis was carried out by HPLC using Zorbax Eclips XDB-C18 (150 x 4.6 mm I.D x 5 microm particle size) column with acetonitrile: water 25:75 v/v mobile phase and UV detection at 210 nm. The liquid-liquid extraction with chloroform was reproducible and sensitive. The procedure was validated in terms of linearity (0.996<r<0.999) for concentrations ranging from 1 to 200 microg/ml, repeatability (RSD 4.4% at 100 microg/ml, n=10) extraction recovery (91.7% at 100 microg/g, 77.3% at 20 microg/g), limit of detection (S/N ratio=3, 0.7 microg/ml) and limit of quantification (S/N ratio=10, 2.4 microg/ml). The method was found satisfactory and successfully applied in fatal cases of animals and birds due to carbofuran poisoning. The fatal carbofuran levels detected were in the range of 42-910 microg/g in crow's gizzard and contents, 50-800 microg/g in dog's stomach contents, 13-20 microg/g in dog's liver, 0.9 microg/g in cow's stomach and contents, 35 microg/g in elephant's stomach and contents.