Study On The Joint Calibration Of3D Laser Scanner And Digital Camera

Joint calibration is one of the key techniques of the integration of laser scanner and camera,and that point cloud and image complement each other’ advantage. Now one commonly usedmethod of joint calibration is achieved by the way of human assistant, this will involve humanerror and the degree of automation is low. Another method is achieved based on the2D target.This model is limited by the characteristics of target and the experimental environment. Thispaper proposes the Joint calibration method based on3D Tridimensional Target, establishes thejoint calibration model, and all these models are validated by experiments. The maincontributions are as follows：1. error sources of3D laser scanners and scanner calibration models are studied on based onthe analysis of working principle of3D laser scanning system.2.3D Tridimensional Target is designed with circular artificial retro-reflective target (RRT)as common points. A new fast self-adaptive localization algorithm of is proposed; this algorithmcan achieve the localization of RRT in the point cloud and image, which can set the stage for theapplication of3D tridimensional target. The external camera calibration and joint calibration arerealized based on the3D Tridimensional Target.3. A ranging error correction model based on intensity is built up. It can correct the rangingerror in relation to intensity; this improves the quality of original point cloud. and this modelmust have important referential significance to instrument calibration which adopts the similarranging principle.4. Joint calibration model based on3D Tridimensional Target is built up. It is validatedthrough mathematical simulation experiment and hardware-in-the-loop (HWIL) simulationexperiment based on the working principle of laser scanner and camera. The validity androbustness of model are validated through simulation experiment.5．An experimental platform is programmed to realize the joint calibration based on theanalysis of functional requirements, some examples are depicted to validate the methods in thispaper.The two sensors can achieve synchronization in space by means of joint calibration ofscanner and digital camera; it can provide a basis for the integration of point cloud data andimage data and fully exploit the functionality of the camera in scanning system.