CoPa: General Robotic Manipulation through Spatial Constraints of Parts with Foundation Models

Foundation models pre-trained on web-scale data are shown to encapsulate extensive world knowledge beneficial for robotic manipulation in the form of task planning. However, the actual physical implementation of these plans often relies on task-specific learning methods, which require significant data collection and struggle with generalizability. In this work, we introduce Robotic Manipulation through Spatial Constraints of Parts (CoPa), a novel framework that leverages the common sense knowledge embedded within foundation models to generate a sequence of 6-DoF end-effector poses for open-world robotic manipulation. Specifically, we decompose the manipulation process into two phases: task-oriented grasping and task-aware motion planning. In the task-oriented grasping phase, we employ foundation vision-language models (VLMs) to select the object's grasping part through a novel coarse-to-fine grounding mechanism. During the task-aware motion planning phase, VLMs are utilized again to identify the spatial geometry constraints of task-relevant object parts, which are then used to derive post-grasp poses. We also demonstrate how CoPa can be seamlessly integrated with existing robotic planning algorithms to accomplish complex, long-horizon tasks. Our comprehensive real-world experiments show that CoPa possesses a fine-grained physical understanding of scenes, capable of handling open-set instructions and objects with minimal prompt engineering and without additional training. Project page: https://copa-2024.github.io

Solid Texture Synthesis using Generative Adversarial Networks

Solid texture synthesis, as an effective way to extend 2D exemplar to a volumetric texture, exhibits advantages in numerous application domains. However, existing methods generally suffer from synthesis distortion due to the under-utilization of information. In this paper, we propose a novel approach for the solid texture synthesis based on generative adversarial networks(GANs), named STS-GAN, learning the distribution of 2D exemplars with volumetric operation in a feature-free manner. The multi-scale discriminators evaluate the similarities between patch exemplars and slices from generated volume, promoting the generator to synthesize realistic solid texture. Experimental results demonstrate that the proposed method can synthesize high-quality solid texture with similar visual characteristics to the exemplar

Stabilizing the Oxygen Lattice and Reversible Oxygen Redox Chemistry through Structural Dimensionality in Lithium-Rich Cathode Oxides.

Lattice-oxygen redox (l-OR) has become an essential companion to the traditional transition-metal (TM) redox charge compensation to achieve high capacity in Li-rich cathode oxides. However, the understanding of l-OR chemistry remains elusive, and a critical question is the structural effect on the stability of l-OR reactions. Herein, the coupling between l-OR and structure dimensionality is studied. We reveal that the evolution of the oxygen-lattice structure upon l-OR in Li-rich TM oxides which have a three-dimensional (3D)-disordered cation framework is relatively stable, which is in direct contrast to the clearly distorted oxygen-lattice framework in Li-rich oxides which have a two-dimensional (2D)/3D-ordered cation structure. Our results highlight the role of structure dimensionality in stabilizing the oxygen lattice in reversible l-OR, which broadens the horizon for designing high-energy-density Li-rich cathode oxides with stable l-OR chemistry

Experimental Study of Foam Flooding in Low Permeability Sandstones: Effects of Rock Permeability and Microscopic Heterogeneity

Foam flooding (or injection of foam) is a common technology to enhance oil recovery. Although the effects of permeability on foam flooding were well studied in many laboratory experiments, little research has been focused on the specificity of low permeability. In this paper, a series of constant-quality nitrogen foam flow experiments were conducted to investigate the effects of permeability on the foam performance and oil displacement efficiency. Moreover, the results indicated that foam can be generated in low permeability porous media. With uniform experimental conditions, the higher permeability core has a bigger recovery amplification and greater decreasing range of water cut decline. Furthermore, the effect of microscopic heterogeneities of low permeability reservoir on foam displacement is considered. Moreover, experimental comparative analysis with different microscopic heterogeneity cores showed that, in low permeability condition, homogeneous porous media has a better prospects of oil-displacement. Finally, in this work, the results of the permeability effects on the foam performance and oil displacement efficiency exemplify a potential to apply the technology to low permeability reservoir

Assessment of the influence of using green tea waste and fish waste as soil amendments for biosolarization on the growth of lettuce (Lactuca sativa L. var. ramosa Hort.)

IntroductionSafe and efficient treatment of organic waste is crucial to developing a sustainable food system around the world. Soil biosolarization (SBS) is a soil treatment technique that can use organic solid wastes to treat the soil in a way that is alternative to the use of chemical fumigants to improve soil fertility in agriculture.MethodsIn this study, two types of organic food wastes, green tea waste (GTW) and fish waste (FW), were evaluated for the feasibility of being applied as soil amendments within simulations of high-temperature cycle SBS. The evaluation was conducted by execution of three groups of measurements: gas and organic volatile emission profile, residual soil phytotoxicity and weed suppression, and cultivar growth (Lactuca sativa L. var. ramosa Hort.).Results and DiscussionGreen tea waste contributed to elevated levels of soil respiration and the evolution of signature volatile organic compounds during the simulated SBS. In the soil amended with green tea waste and then undergoing SBS the phyto compatibility was restored after residual phytotoxicity dissipation and a complete weed suppression was achieved. By using an application rate of 2.5% (w/w, mass fraction of green tea waste in total soil-waste mixture) green tea waste cultivar growth comparable to that of the non-treated soil (NTS) group was attained, with a more efficient nitrogen utilization and higher residual soil nitrogen content enabling the improvement of the continuous cropping system. FW at 1% (w/w, mass fraction of FW in total soil-waste mixture) promoted cultivar growth despite the significant reduction of the nitrogen (p value=0.02) and phosphorus (p value=0.03) contents in the cultivar leaves. A significant increase of the sodium content together with an increase of iron and chromium, which exceeded the permissible limit, were observed. These results provide new information about amendment selection for the SBS process

Spin State Disproportionation in Insulating Ferromagnetic LaCoO3 Epitaxial Thin Films

The origin of insulating ferromagnetism in epitaxial LaCoO3 films under tensile strain remains elusive despite extensive research efforts have been devoted. Surprisingly, the spin state of its Co ions, the main parameter of its ferromagnetism, is still to be determined. Here, we have systematically investigated the spin state in epitaxial LaCoO3 thin films to clarify the mechanism of strain induced ferromagnetism using element-specific x-ray absorption spectroscopy and dichroism. Combining with the configuration interaction cluster calculations, we unambiguously demonstrate that Co3+ in LaCoO3 films under compressive strain (on LaAlO3 substrate) are practically a low spin state, whereas Co3+ in LaCoO3 films under tensile strain (on SrTiO3 substrate) have mixed high spin and low spin states with a ratio close to 1:3. From the identification of this spin state ratio, we infer that the dark strips observed by high-resolution scanning transmission electron microscopy indicate the position of Co3+ high spin state, i.e., an observation of a spin state disproportionation in tensile-strained LaCoO3 films. This consequently explains the nature of ferromagnetism in LaCoO3 films

Exploring a Novel Reservoir Impoundment Operation Framework for Facilitating Hydropower Sustainability

Reservoir impoundment operation has far-reaching effects on the synergies of hydropower output, floodwater utilization, and carbon fluxes, but flood risk is significantly increasing, which is especially true when shifting to earlier impoundment timings and lifting reservoir water levels. This study proposed a novel reservoir impoundment operation framework driven by flood prevention, hydropower production, floodwater utilization, and carbon emission management. The Three Gorges Reservoir in the Yangtze River was selected as a case study. The results demonstrated that flood prevention safety could be guaranteed with the initial impoundment timings on and after the first of September. The best scheme of reservoir impoundment operation could efficiently boost synergistic benefits by enhancing 2.98 billion kW·h (8.8%) hydropower output and 6.4% water impoundment rate and decreasing greenhouse gas (GHG) fluxes and carbon budget by 28.15 GgCO2e/yr (4.6%) and 0.44 (23.1%), respectively, compared with the standard operation policy. This study can not only provide scientific and technical support for reservoir impoundment operations, benefiting water–carbon synergies, but can also suggest policymakers with various favorable advancing impoundment timing and lifting reservoir water level schemes to experience related risks and benefits in the interest of hydropower sustainability