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Safe and efficient path planning for mobile robots in dynamic environments is still a challenging research topic. Most approaches use separate algorithms for global path planning and local obstacle avoidance. Furthermore, planning a path for a sequence of goals is mostly done by planning to each next goal individually. These two strategies generally result in sub-optimal navigation strategies. In this paper, we present an algorithm which addresses these problems in a single combined approach. For this purpose, we model the static and dynamic risk of the environment in a consistent way and propose a novel graph structure based on a state x time x goal lattice with hybrid dimensionality. It allows the joint planning for multiple goals while incorporating collision risk due to dynamic and static obstacles. It computes hybrid solutions which are part trajectory and part path. Finally, we provide some results of our algorithm in action to prove its high quality solutions and real-time capability

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The paper describes an autonomous water vehicle (ASV) capable of autonomously mapping shallow water environments above and below the water surface. Over the past two years, Fraunhofer IOSB has developed a system that is fully electrified and equipped with extensive sensor technology (multibeam sonar, lidar, cameras, IMU, GNSS). For autonomous navigation, the complete processing pipeline was implemented, from obstacle detection and avoidance to trajectory planning and control to multi-sensor localization and mapping. Above water, both lidar-based mapping and photogrammetric methods are used; underwater, bathymetry data is obtained using sonar. The interface to the operator is realized by an interactive digital map table, which allows intuitive mission specification and evaluation.

We present a local stereo matching method for hyperspectral camera data, allowing multiple usage of camera hardware and imaging data such as for object classification or spectral analysis and multichannel input to the correspondence problem. The matching process combines correlation-based similarity measures for pixel windows utilizing all 16 spectral channels followed by a consistency check for disparity selection. We evaluate stereo-processing methods focusing on effectiveness and runtime of the processing on a CPU and analyze parallelization possibilities. Based on the results of the evaluation on the CPU, we implement the optimized stereo matching for images with 16 channels on a graphics processing unit (GPU) utilizing the Compute Unified Device Architecture (CUDA). The parallel processing of the calculation steps to obtain the disparity image on the GPU achieves more than 27× speed up, resulting in calculation and post-processing of hyperspectral images with 8 -13 Hz, depending on the selection of maximum disparity. The 3D reconstruction achieves a mean square error of 0.0267 m 2 in distance measurements from 5 -10 m.