Indoor surveying apparatus
An indoor surveying apparatus comprises a 2D range finder, means for automatically aligning 2D range finder data and computing a 2D map of the environment, a calibrated optical imaging system for capturing images of environment, and means for establishing positions and extents of walls, doors, and windows and for drawing floor plans using the computed 2D map and calibrated images where 2D range finder data is missing. It is further contemplated that the imaging system can also be part of the range finder, that the range finder can be a scanning laser range finder, that the imaging system can include a panoramic lens with 180 degree field of view, that the apparatus can further include an IMU, an electronic compass, a panoramic rotator, and means for measuring positions of points on the floor using the image data.
1. An indoor surveying apparatus comprising:
a 2D range finder having a 2D measurement surface, whereby the 2D range finder measures a 2D data set comprised of a plurality of points located at intersection of the 2D measurement surface and surfaces of other objects;
a computing device executing an algorithm for automatically projecting 2D data sets measured by the 2D range finder onto a horizontal plane and automatically aligning the projected 2D data sets to construct a map of indoor environment consisting of points of the projected 2D data sets;
a calibrated optical imaging system coupled to the 2D range finder, comprising an image sensor and an objective lens, the calibrated optical imaging system having calibration coefficients that depend on a focal length and a distortion of the objective lens, a position and an orientation of the image sensor relative to the objective lens, and a position and an orientation of the objective lens relative to the 2D range finder, whereby points from a 2D data set measured by the 2D range finder can be projected onto an image captured by the calibrated optical imaging system using the calibration coefficients; and
a computing device executing an algorithm for establishing positions and extents of walls, doors, and windows and for drawing floor plans using information from the map of indoor environment, images captured by the calibrated optical imaging system, and the calibration coefficients of the calibrated optical imaging system, whereby the images can be used for establishing positions and extents of walls, doors, and windows where the map of indoor environment is missing.
2. A surveying apparatus according to claim 1 , wherein the 2D range finder is a scanning laser range finder.
3. A surveying apparatus according to claim 1 , wherein the 2D range finder is a triangulation laser range finger comprising a laser source with a 2D emission pattern and the calibrated optical imaging system, whereby the calibrated optical imaging system is used for both capturing images and measuring 2D data sets.
4. A surveying apparatus according to claim 1 , wherein the objective lens of the calibrated optical imaging system is a panoramic objective lens having an optic axis, an entrance pupil, and a field of view of at least 180 degrees.
5. A surveying apparatus according to claim 4 , further comprising a stand and a rotator through which the surveying apparatus is coupled to the stand, the rotator having a rotation axis that is substantially perpendicular to the optic axis of the objective lens and passes substantially through the entrance pupil of the objective lens, whereby the rotator enables the surveying apparatus to be rotated around the rotation axis relative to the stand.
6. A surveying apparatus according to claim 5 , wherein the rotator enables the surveying apparatus to be repeatably rotated into two angular positions that are substantially 180 degrees apart from each other.
7. A surveying apparatus according to claim 5 , wherein the rotator enables the surveying apparatus to be repeatably rotated into three angular positions that are substantially 120 degrees apart from each other.
8. A surveying apparatus according to claim 1 , further comprising an inertial measurement unit.
9. A surveying apparatus according to claim 1 , further comprising an electronic compass.
10. A surveying apparatus according to claim 1 , further comprising a computing device executing an algorithm for computing position of a point on a floor relative to the surveying apparatus by triangulation using images captured by the calibrated optical imaging system, the calibration coefficients of the calibrated optical imaging system, and a distance from the calibrated optical imaging system to the floor.