Algorithms Research Of2D Laser Scanner Based On DSP

The main research purpose of this paper is to suppress hysteresis effect ofpiezoelectric stack through the establishment of algorithm model and method of softwarecontrol in order to make the nonlinearity of a single fast-steering-mirror system be reducedto less than1%in normal operating condition. The main research content of this paper iscombining a pair of fast-steering-mirror system adjusted with hysteresis effect into a2Dlaser scanner system at first. Afterwards, to achieve specific scanning waveform throughload triangular waveform drive voltage with different frequency to twofast-steering-mirror systems respectively.In addition to hysteresis effect of piezoelectric ceramics, the circumstance of lightincidence, reflection and emergence is an important content of this paper. Because most ofthe work in this paper is achieved by the computer simulation of MATLAB software andDSP control by using C language programming, it is need making all the calculationprocess programming. Considering this, matrix form of the reflection law is introduced inthis paper. At the same time, calculate and analyze some error of the two-dimensionalscanning system, such as cushion error and incident point position error. Because theseerrors in our development of small Angle deflection of2D scanning system are just at0.03%and0.02%respectively, they can be ignored for reducing the complexity of thecalculation and improving the efficiency of the system operation.In this paper, the key is how to suppress hysteresis effect of each fast-steering-mirrorsystem in2D scanning system. Some mainstream open loop control algorithm has beenintroduced, especially focusing on the analysis of the inverse control model andfeed-forward compensation method with hysteresis effect correction effect. The inversecontrol model based on elliptic polar coordinate makes the system nonlinearity from morethan6%to less than2%, but still failed to reach the precision of the system requirements.However, the feed-forward compensation method makes the system nonlinearity under1% and has self learning characteristics, namely can make corresponding adjustmentautomatically as the change of external environment, so it is used as automatic correctionpart of DSP control.Finally, it is discussed how to control F2812DSP to implement output of idealtriangular waveform drive voltage and combine feed-forward compensation method forthe suppression of hysteresis effect. Besides, scanning waveform has been measured onthe test platform of the2D scanning system, obtains the scanning waveforms whenscanning frequency ratio of fast-steering-mirror system X and Y is3:1and5:1respectively.It is consistent with simulation results and system linearity gets great improvement.