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

触觉人机交互机制和系统在各种工程和科学活动中发挥着关键作用，这些活动依赖于虚拟对象组装的基本任务，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、遥操作和消费应用。开发这种实用的交互系统的关键长期挑战之一是缺乏有效地帮助用户探索虚拟环境的指导力的适当公式，从排斥碰撞到吸引适当的接触。第二个困难是实现能够保持可接受的触觉刷新率的有效实现。目前这些开放问题的最新解决方案是针对严格受限的形状和运动类别开发的，并且严重依赖于利用严重几何限制的启发式算法。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，该模型支持空间关系，从而正确地组装任意复杂的形状。项目成果将导致智能人-计算机或人-机器人系统的有效交互机制，并将为通用和全自动装配规划器的开发打开大门，同时在广泛的工业、科学和消费应用中释放依赖交互式装配任务的活动的表达和生产力的新水平，这些领域包括3D用户界面、工程以及医疗和辅助技术。PI的行业伙伴关系将促进积极和广泛的技术转让。为此，能量函数被表示为依赖于形状的亲和场的卷积，其依赖于空间连续的、定义良好的和稳健的密度函数的新概念，称为骨架密度函数(SDF)，其极限中的子级集与中轴的隐式定义相关。重要的是，提出的能量场导致了第一种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，提出的方法完全避免了现有触觉组装方法中常见的启发式配方和人工干预。PI的初步结果表明，该研究可以将当前触觉模拟中常见的自由运动和精密装配两个触觉交互阶段统一为单一的交互模式，并提出所谓虚拟夹具的通用自动约束模型，而不对所涉及的装配特征和形状的类型进行限制性假设。

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.