This article investigates the challenge of enabling multifinger hands to perform human-like functional grasping for various intentions. However, accomplishing functional grasping in real robot hands present many challenges, including handling generalization ability for kinematically diverse robot hands, generating intention-conditioned grasps for a large variety of objects, and incomplete perception from a single-view camera. In this work, we first propose a six-step functional grasp synthesis algorithm based on fine-grained contact modeling. With the fine-grained contact-based optimization and learned dense shape correspondence, the algorithm is adaptable to various objects of the same category and a wide range of multifinger hands using few demonstrations. Second, over 10 k functional grasps are synthesized to train our neural network, named DexFG-Net, which generates intention-conditioned grasps based on reconstructed object. Extensive experiments in the simulation and physical grasps indicate that the grasp synthesis algorithm can produce human-like functional grasp with robust stability and functionality, and the DexFG-Net can generate plausible and human-like intention-conditioned grasping postures for anthropomorphic hands.

Grasping in cluttered environments is one of the most fundamental skills in robotic manipulation. Most of the current works focus on estimating grasp poses for parallel-jaw or suction-cup end effectors. However, the study for dexterous anthropomorphic hand grasping in clutter remains a great challenge. In this paper, we propose HGC-Net, a single-shot network that learns to predict dense hand grasp configurations in clutter from single-view point cloud input. Our end-to-end neural network can predict hand grasp proposals efficiently and effectively. To enhance generalization, we built a large-scale synthetic grasping dataset with 179 household objects, 5K cluttered scenes and over 10M hand annotations. Experiments in simulation show that our model can predict dense and robust hand grasps and clear over 78% of unseen objects in clutter without any post-processing and outperform baseline methods by a large margin. Experiments on the real robot platform also demonstrate that the model trained on synthetic data performs well in natural environments. Code is available at https://github.com/yimingli1998/hgc_net.

Object grasping in cluttered scenes is a widely investigated field of robot manipulation. Most of the current works focus on estimating grasp pose from point clouds based on an efficient single-shot grasp detection network. However, due to the lack of geometry awareness of the local grasping area, it may cause severe collisions and unstable grasp configurations. In this paper, we propose a two-stage grasp pose refinement network which detects grasps globally while fine-tuning low-quality grasps and filtering noisy grasps locally. Furthermore, we extend the 6-DoF grasp with an extra dimension as grasp width which is critical for collisionless grasping in cluttered scenes. It takes a single-view point cloud as input and predicts dense and precise grasp configurations. To enhance the generalization ability, we build a synthetic single-object grasp dataset including 150 commodities of various shapes, and a complex multi-object cluttered scene dataset including 100k point clouds with robust, dense grasp poses and mask annotations. Experiments conducted on Yumi IRB-1400 Robot demonstrate that the model trained on our dataset performs well in real environments and outperforms previous methods by a large margin.

Multi-scale object detection (MOD) is one of the remaining challenges for satellite imagery. To improve the performance of MOD task, YOLT (You Only Look Twice) has achieved a good accuracy in high resolution remote sensing images. Motivated by the state-of-art object detection method for satellite imagery, we explored and achieved the state-of-the-art accuracy based on the standard YOLT for MOD task by providing a novel method with enough experimental results and model comparison on the typical multi-scale satellite imagery dataset. First, we divide objects into three categories according to the scale of objects. Then, different training strategies are used to train the classifier and detector for different scale objects. Finally, multi-scale detection chips are stitched and fused to get more accurate localization and classification as the final predicted results for MOD in satellite imagery. Experiments have been conducted over dataset from the second stage of AIIA1Cup Competition of Typical Object Recognition for Satellite Imagery in Small Samples compared with the standard YOLT and Faster R-CNN, which demonstrates the effectiveness and the comparable detection performance of our proposed pipeline.

Object tracking is one of the important tasks for mobile robot, and developing a robust and real-time visual tracking algorithm which can adaptively capture the varying appearance of target under challenging conditions for mobile robot is still an open problem. The main challenges of visual tracking for mobile robot come from variation of target's appearance and disturbance of environment. To cope with these problems, one of the most important topics is how to select the best tracking features. In this paper, we propose a novel adaptive probabilistic tracking method with discriminative feature selection for mobile robot Different from the existing adaptive tracking algorithms which select the discriminative features in a finite feature set, the proposed method treats feature selection as an estimation problem of the best feature tunable parameters in a continuous space. The estimation of the best tunable parameters and object tracking are implemented via different particle filters with novel observation models. A novel target model updating strategy is also proposed to adapt to the varying appearance of target and resist gradual drift. Experiments show the robustness of the proposed method under challenging conditions.

Sparse coding has been used for target appearance modeling and applied successfully in visual tracking. However, noise may be inevitably introduced into the representation due to background clutter. To cope with this problem, we propose a saliency weighted sparse coding appearance model for visual tracking. Firstly, a spectral filtering based visual attention computational model, which combines both bottom-up and top-down visual attention, is proposed to calculate saliency map. Secondly, pooling operation in sparse coding is weighted by calculated saliency map to help target representation focus on distinctive features and suppress background clutter. Extensive experiments on a recently proposed tracking benchmark demonstrate that the proposed algorithm outperforms state-of-the-art methods in tracking objects under background clutter.