Method and system for fusing data arising from image sensors and from motion or position sensors

摘要

A method and a system are provided integrating inter-pose constraints, which are weighted in a step of “bundle adjustment” in a localization application (SLAM). The inertial data associated with a motion model serve to predict the pose of the system at the instant of a new image. This prediction is then used to construct an inter-pose constraint. A technique arising from learning theory selects the weighting coefficient (ratio of the noise of the covariance signals) in an efficient manner. The inter-pose constraint thus weighted is then integrated within the cost function of the bundle adjustment.

主权项

1. A method for fusing data arising from a first image sensor and from a motion and/or position measuring module, the said first sensor and the said motion and/or position measuring module being integral and forming a device, the method being executed by a processing module in order to localize the said device, comprising:
a first step consisting of acquiring several points on the images in order to define a current pose ptc of the device, including image camera and motion and/or position measuring module, for a given instant t, a prediction step of the predicted pose {circumflex over (p)}tk of the device (camera and motion/position sensor) for the same given instant t and using the measurements from the motion and/or position measuring module, a step where we determine an associated constraint εk for the sensor k of the device (camera c and sensor k), a step where we automatically determine a weighting coefficient λt of the said constraint, an estimation step of the current pose pt of the said device, a step of simultaneous optimization of the poses of the device (camera+sensor) by the bundle adjustment technique using the following cost function:EBA⁡(Xt,Zt)=∑t′=t-(N-1)t⁢ɛc2⁡([pt′⁢s],zt′c)+∑t′=t-(N-1)t⁢Ep⁡([pt′⁢s],Zt) with
Ep(xt,Zt)=εc2(xt,ztc)+λt2εk2(xt,ztk)εc2: reprojection errors of the scene in the imagesxt: =[ps] the pose of the device and the sceneztc: =the observations of the scene detected in the image of the camera c at the instant tZt=[ztcztk] combination of all the measurements for all the camera c sensors and of the sensors k of motion and/or position module at an instant t.