A novel visual navigation method based on grating projection stereo vision for mobile robot in dark environment is proposed. This method is combining with grating projection profilometry of plane structured light and stereo vision technology. It can be employed to realize obstacle detection, SLAM (Simultaneous Localization and Mapping) and vision odometry for mobile robot navigation in dark environment without the image match in stereo vision technology and without phase unwrapping in the grating projection profilometry. First, we research the new vision sensor theoretical, and build geometric and mathematical model of the grating projection stereo vision system. Second, the computational method of 3D coordinates of space obstacle in the robot’s visual field is studied, and then the obstacles in the field is located accurately. The result of simulation experiment and analysis shows that this research is useful to break the current autonomous navigation problem of mobile robot in dark environment, and to provide the theoretical basis and exploration direction for further study on navigation of space exploring robot in the dark and without GPS environment.
The stereo visual odometer in vision based on the navigation system is proposed in the paper. The stereo visual odometer
can obtain the motion data to implement the position and attitude estimation of ALV(Autonomous Land Vehicle). Two
key technology in the stereo vision odometer are dissertated. The first is using SIFT(Scale Invariant Feature Transform)
to extract suitable feature, match points pairs in the feature, and track the feature of fore and after frames of the same
point on the object. The second is using matching and tracking to obtain the different 3-D coordinate of the feature of the
point on the object, and to compute the motion parameters by motion estimate. The unknown outdoor environment is
adopted in the experiment. The results show that the stereo vision odometer is more accurate, and the measurement error
dose not increase with the movement distance increasing. It can be used as an important supplement of conventional
odometer.
The unwrapped phase distribution on reference planes with different heights in grating project profilometry are analyzed
and synthesized. Then a two-parameter second-order rational polynomial to express the uneven phases on every plane is
proposed. A first-order Taylor series expansion is employed to obtain the polynomial coefficients of rational polynomial
based on least-square iterative estimation method. By this method, phases on all the reference planes are retrieved
precisely and extended to the full field. The results of experiences proved that the method not only can retrieve the
phases distribution on the full field from parts reference planes, but geometrical parameter error, real reference plane
profile error and random error are decreased, and coordinate measuring precision is also increased.
The image feature extract method of image pattern recognition algorithm is studied in the paper. A high speed and
real-time method of image locating and feature extract is presented. And the method mainly consists of two key
technologies, one is to locate the target area of measured object using mask matrix method, the other is to extract the
edge feature based on the template matching method. The experiment results show that the method of image feature
extracting is a high speed and high precision image recognition algorithm, and it can be satisfied the high-speed and
real-time requests of on-line detection.
The binocular vision measurement system is adopted with two CCDs and their optical axes are vertical to obtain the attitude of dynamic missile. Two methods to get the axis vector of the measured missile are discussed in the paper. One is to derive the linear equation of the missile axis' projection line in space coordinate using axle wire method. The other is to obtain the axis vector of measured object based on vertical principle of two CCDs' optical axes. Lastly, with the measured missile attitude measurement principle, the moving attitude from the axis vector obtained above is discussed in the paper too. The result of simulation experiment and analysis shows that the measurement method has higher precision, and can meet the measurement requirement for the dynamic parameter of moving object in long distance.
The binocular stereo vision measurement system with two CCDs, whose optic axes are parallel, is presented in this paper to measure the 3D profile of a dynamic object in long distance. Two key technologies in the binocular stereo vision measurement system are dissertated. The first technology is to extract the features of two images which are separately gathered by two CCDs. The second technology is to process the feature pairs to build a corresponding relationship of different feature points of the same space point and get the disparity image. Experiment results of stereo matching and 3D profile of measured object are given. These results show that the mathematic model is simple relatively, stereo matching is easy comparative, and the measurement is rapid. And the presented binocular stereo vision measurement system can be used to measure the attitude and 3D profile of flying missile, and the measurement system which requires some hardware, can be realized easily, operated stably and is of high measurement precision.
A novel Si-based MOEMS acceleration seismic geophone, based on M-Z interferometry, is present in this paper. In one silicon chip, several elements including four silicon beams,seismic mass, a polarizer, M-Z waveguide interferometer and acousto-optic phase modulator are integrated. The working principle and the optimization structure design of the acceleration seismic geophone are given. The simulation result performed in FEM software ANSYS agrees with the theoretical analysis well. The main design parameters of the geophone system is as following: resonance frequency: 1353 Hz; phase detection sensitivity ΔΦ/a: 1.2×10-4rad/m/s2.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.