Research On The Design Of The Photoelectric Reference Scale For Laser Theodolite System Orientation

Because of the characters of high precision,wild measurement range,easy to carry,the laser theodolite system has been playing an important role in measuring for the coordinates in the large space and size with high precision.It has been using in the aerospace,shipbuilding,measuring the bridge and so on.Before the laser theodolite measurement system starts to work,the space position and attitude between theodolites must be determinated first.This process is called measurement system orientation.The traditional method is based on fixed length reference scale.Whole process of orientating the measurement system needs manual intervention,so it wastes time,imports random error.To get a ideal result,one time of orientating is not enough.The new non-orthogonal shafting "laser theodolite" measurement system replaces the telescope with laser beam,so the traditional orientation method can’t be used.The traditional laser theodolite and the new non-orthogonal shafting "laser theodolite" both based on laser beam.Thus,this paper proposes and studies a construction technology of intelligent “variable length” photoelectric reference scale based on high-precision photoelectric position sensitive detector.It achieves “variable length” reference,wireless transmission,guiding the space intersection,orientating the laser theodolite measurement system automatically,but no need of aiming at special point.The study details are as follows:1.Analysis the coordinate measurement systems in the large space and size,high precision and their principle.Introduce common directional reference scale’s structure at home and abroad.Based on that,propose a new kind of reference scale with variable length for laser theodolite system orientation.Introduce its function and feature simply.2.Two kinds of the orientation methods of laser theodolite system are given.After that,propose the measurement system’s orientation program and process based on variable length photoelectric reference scale.3.According to physics,the lateral photoelectric effect of PSD is analyzed.Based on that,we choose the S5991 PSD.Study on the PSD’s main parameters,factorsinfluencing its precision and methods to reduce noise.In order to adapt to the outdoor environment,introduce methods to reduce the impact of backgound light.4.The hardware and structure design of the intelligent “variable length” photoelectric reference scale is completed.The hardware part includes PSD signal processing module,Bluetooth module and data processing module.List the common materials of reference scale,complete in the production.5.Present the method to calibrate the spatial position relationship of the reference scale.Analyze the system model of three-coordinate with laser detector and calibration method based on that.6.Finish the calibrating process and evaluation of the accuracy of variable length photoelectric reference scale by designing experiments.