CHS: Small: Interactive Haptic Assembly and Docking for 3D Shapes

从蛋白质对接、药物设计和远程手术，到先进制造、康复、机器人、远程操作和消费者应用，触觉人机交互机制和系统在依赖虚拟物体组装的各种工程和科学活动中发挥着关键作用。在开发这种实用的交互系统中，一个长期存在的关键挑战是缺乏一个适当的引导力的公式来有效地帮助用户探索虚拟环境，从排斥碰撞到吸引适当的接触。第二个困难是实现有效的实现，保持可接受的触觉刷新率。目前，这些开放性问题的最先进的解决方案是针对严重受限的形状和运动类开发的，并且严重依赖于利用剧烈几何限制的启发式。为了解决这些问题，PI的这项研究的目标是为人工能量场开发一个纯几何模型，该模型有利于空间关系，从而导致任意复杂形状的适当组装。项目成果将导致智能人机或人机系统的有效交互机制，并将为通用和全自动装配计划器的发展打开大门，同时在广泛的工业，科学和消费者应用中，在3D用户界面，工程，医疗和辅助技术。PI的工业伙伴关系将促进积极和广泛的技术转让。为了达到这些目的，能量函数以依赖于形状的亲和场的卷积来表示，该亲和场依赖于空间连续的、定义良好的、健壮的密度函数的新概念，称为骨架密度函数（SDF），其极限中的子水平集与内轴线的隐式定义相关。重要的是，提出的能量场导致了第一个实用和自动的方法来检测有助于正确对准或装配的关键特征，以及虚拟装配所需的几何约束。此外，该方法完全避免了现有触觉装配方法中常见的启发式配方和人工干预。PI的初步结果表明，本研究可以将当前触觉仿真中常见的自由运动和精密装配两个触觉交互阶段统一为一个单一的交互模式，并为所谓的虚拟夹具提供了一个通用的自动约束模型，对所涉及的装配特征和形状的类型没有任何限制假设。

Haptic human-computer interaction mechanisms and systems play a critical role in a variety of engineering and scientific activities that rely on the fundamental task of virtual object assembly, from protein docking, drug design and tele-surgery, to advanced manufacturing, rehabilitation, robotics, teleoperation and consumer applications. One of the key long-standing challenges in developing such practical interactive systems is the lack of a proper formulation of the guidance forces that effectively assist the user in the exploration of the virtual environment, from repulsing collisions to attracting proper contact. A secondary difficulty is that of achieving an efficient implementation that can maintain an acceptable haptic refresh rate. Current state-of-the art solutions to these open problems have been developed for severely restricted classes of shapes and motions, and rely heavily on heuristics that exploit drastic geometric limitations. To address these issues, the PI's goal of this research is to develop a purely geometric model for an artificial energy field that favors spatial relations leading to proper assembly of arbitrarily complex shapes. Project outcomes will lead to effective interaction mechanisms for intelligent human-computer or human-robot systems and will open the doors to the development of generic and fully automated assembly planners while simultaneously unlocking new levels of expression and productivity in activities that rely on interactive assembly tasks in a broad range of industrial, scientific and consumer applications, in domains as diverse as 3D user interfaces, engineering, and medical and assistive technologies. The PI's industrial partnerships will facilitate aggressive and widespread technology transfer. To these ends, the energy function is expressed in terms of a convolution of shape-dependent affinity fields that rely on the novel concept of a space-continuous, well-defined, and robust density function, called the Skeletal Density Functions (SDF), whose sublevel sets in the limit are related to an implicit definition of the medial axis. Importantly, the proposed energy field leads to the first practical and automatic approach to detect key features that contribute to proper alignment or assembly, as well as the geometric constraints required for virtual assembly. Moreover, the proposed approach completely avoids the heuristic recipes and manual intervention that are common to existing methods for haptic assembly. The PI's preliminary results show that this research can unify the two haptic interaction phases of free motion and precision assembly, which are common in current haptic simulations, into a single interaction mode, and suggest a generic and automatic constraint model for the so-called virtual fixtures, with no restrictive assumption on the types of the assembly features and shapes involved.