Research On Key Technology Of The Chromosome Micro Manipulation System

Bioengineering shows great effect on the national economy, together withmicroelectronics, advanced materials technology and new energy technology. Most of itstechnologies such as organelle transplantation, gene injection and chromosome microdissection involve micro manipulation. Chromosome micro dissection is widely used onthe research of chromosome evolution and genome structure, etc. However, chromosomemicro manipulator is the key factor that influences the development of chromosomemicro dissection.This article aims to increase the chromosome dissection accuracy and efficiency. Byanalyzing current chromosome micro manipulation systems, this article proposes a novelmulti-DOF redundant chromosome micro dissection system along with the analysis of itsperformance design, calibration and accuracy. The major contents are as follows:(1) According to the disadvantages of current chromosome micro dissectionmanipulator such as low DOF and small work space, etc. a novel macro micro dual drivechromosome dissection system was proposed. Both design idea and parameter selectionsof its components are shown. Work space and resolution are all measured both for macroand micro manipulators.(2) The chromosome dissection process, which is proposed based on thecharacteristics of chromosome dissection, is composed of two separate parts. One part ismacro movement, another is micro movement. The corresponding kinematic analysis of 6-PPPS macro manipulator,6-PSU macro manipulator and6-PSS micro manipulator areincluded along with the macro and micro movements.(3) A new external calibration method named rolling iterative calibration methodwas proposed. This method utilizes laser tracker to measure the displacements of all thelinear joints and the pose of the moving platform. Besides, it can solve the errorparameters one after another rather than all together. Comparing the proposed methodwith common method on the6-PPPS macro manipulator, the results can demonstrate thatrolling iterative calibration method can solve the non-convergence problem duringmassive calculation.(4) A method for accuracy analysis on non-redundant parallel robots with identicalserial limbs was proposed. By introducing a second level partial derivative matrix calledEMGJI matrix, the influences of geometry parameters acting on the moving platformthrough joint variables can be studied. The traditional differential method usuallyconducts partial derivative on all parameters. However, according to the rules weobtained, certain parameters can be excluded in advance from the calculation. Simulationbased on the6-PPPS and the6-PSU macro manipulators shows that calculation time onaccuracy analysis drops significantly for the proposed method comparing with traditionalmethod.(5) The deformation model of the glass needle during chromosome dissection hasbeen built. The influences on the deformation through puncture angle and surface frictionhas been described. The chromosome dissection experiment also demonstrates thevalidation of the proposed system.