1 June 2007 in The International Journal of Robotics Research
In this paper we present a tutorial introduction to two important senses for biological and robotic systems — inertial and visual perception. We discuss the fundamentals of these two sensing modalities from a biological and an engineering perspective. Digital camera chips and micro-machined accelerometers and gyroscopes are now commodities, and when combined with today's available computing can provide robust estimates of self-motion as well 3D scene structure, without external infrastructure. We discuss the complementarity of these sensors, describe some fundamental approaches to fusing their outputs and survey the field.
1 June 2007 in The International Journal of Robotics Research
This paper proposes an approach to calibrate off-the-shelf cameras and inertial sensors to have a useful integrated system to be used in static and dynamic situations. When both sensors are integrated in a system their relative pose needs to be determined. The rotation between the camera and the inertial sensor can be estimated, concurrently with camera calibration, by having both sensors observe the vertical direction in several poses. The camera relies on a vertical chequered planar target and the inertial sensor on gravity to obtain a vertical reference. Depending on the setup and system motion, the translation between the two sensors can also be important. Using a simple passive turntable and static images, the translation can be estimated. The system needs to be placed in several poses and adjusted to turn about the inertial sensor centre, so that the lever arm to the camera can be determined. Simulation and real data results are presented to show the validity and simple requirements of the proposed methods.
23 August 2011 in Robotics and Autonomous Systems
7 March 2013 in IEEE Transactions on Cybernetics
In this paper, we present a Bayesian framework for the active multimodal perception of 3-D structure and motion. The design of this framework finds its inspiration in the role of the dorsal perceptual pathway of the human brain. Its composing models build upon a common egocentric spatial configuration that is naturally fitting for the integration of readings from multiple sensors using a Bayesian approach. In the process, we will contribute with efficient and robust probabilistic solutions for cyclopean geometry-based stereovision and auditory perception based only on binaural cues, modeled using a consistent formalization that allows their hierarchical use as building blocks for the multimodal sensor fusion framework. We will explicitly or implicitly address the most important challenges of sensor fusion using this framework, for vision, audition, and vestibular sensing. Moreover, interaction and navigation require maximal awareness of spatial surroundings, which, in turn, is obtained through active attentional and behavioral exploration of the environment. The computational models described in this paper will support the construction of a simultaneously flexible and powerful robotic implementation of multimodal active perception to be used in real-world applications, such as human-machine interaction or mobile robot navigation.
26 February 2010 in Journal of Real-Time Image Processing