Continuously bending reconfigurable robot manipulators for flexible handling and assembly in confined and remote environments

大多数串联机器人使用传统的刚性连杆设计，具有多个关节和连杆[1]。然而，对于这些机器人在缩小的空间中执行的多个单独任务，较低的自由度（DOF）就足够了[2]。这包括制造电子产品和海上作业等活动，在这些活动中，在狭小的空间和偏远地区工作至关重要。这种情况的其他例子是深海，危险材料处理和空间机器人。虽然足够完成任务，但低DOF限制了工作空间，因此限制了系统的灵活性，阻碍了机器人适应各种任务的能力。对于需要复杂定位的偏远区域内的工作，具有更高DOF的传统机器人手臂似乎更合适，例如，因为更高的DOF允许机器人手臂适应给定的场景，完成更大范围的复杂任务。然而，更高数量的自由度导致机器人更大，更重，有时比特定活动所需的更复杂。当需要满足机器人要求时，这可能会导致特定的限制，例如空间机器人的重量限制。因此，解决这个问题的理想方案是一个简单的，低自由度的机器人，保持系统的灵活性。软机器人手臂，通常使用一个连续弯曲的链接，承诺了许多改进刚性，离散的机械手，如减少尺寸和重量的要求，增加系统的灵活性;然而，这些机器人系统一直在努力实现完全刚性设计的保持强度和精度[3]。最近的研究已经探索了在软的连续体机器人中使用可变刚度连杆进行手术，通过改变机器人的刚度来包含两个系统的方面[4][5]。这一发展使机器人克服了软机器人的强度限制，通过提供一个刚性平台时，机器人是'激活'。然而，目前，不存在具有减少的自由度数量的机器人，其可以适应于具有可变但可控的工作空间的多个任务;这些机器人是在受限和远程环境中实现过程自动化和增强人类操作员能力的需要。本研究旨在联合收割机，改进和扩展现有的用于可重构串联臂的软机器人研究，生产具有减少的自由度数量的机器人，这些机器人可以使用可变刚度连杆来调整其拓扑结构，从而能够执行一系列任务，重点是处理和拾取-放置装配操作。这些系统的理想实现将是在需要具有高DOF性能的减小尺寸/重量的机器人的操作中作为协作机器人，即深海和太空机器人。这些新型机械手具有更大的灵活性，通过适应不同的机器人，同时保持低自由度机器人系统的优点，如重量，尺寸和控制复杂性。拟议的机器人将使用外部可延展链接的串联链制造：可变刚度，柔性，连续弯曲的链接，可以在非刚性状态下手动重新定位，同时在激活时保持其位置。这些可延展的链接将通过旋转关节连接，以便能够执行传统机器人手臂可以执行的操作。

The majority of serial robots use traditional rigid-link designs with multiple joints and links [1]. However, for multiple individual tasks that are performed by these robots in reduced spaces, a lower number of degrees of freedom (DOF) is sufficient [2]. This includes activities such as manufacturing electronics and offshore operations, where working inside reduced spaces and in remote locations is vital. Other examples of such situations are deep sea, hazardous material handling, and space robotics. Whilst sufficient for the task, a low DOF limits the workspace, and therefore the flexibility of the system, hindering the ability for the robot to adapt to various tasks. For work within remote areas that requires complex positioning, a traditional robot arm with higher DOF seems more appropriate for instance, as a higher DOF allows the robot arm to adapt to given scenarios, accomplishing a larger range of complex tasks provided. Nevertheless, a higher number of DOF causes the robot to be larger, heavier, and sometimes more complex than necessary for particular activities. This can cause specific limitations when robotic requirements are needed to be met, for example weight limitations with space robotics. The ideal solution to this problem therefore is a simpler, low DOF robot that maintains the flexibility of the system.Soft robot arms, implemented usually using a single continuously bending link, promise a number of improvements over stiff, discrete manipulators such as reduced size and weight requirements with an increase in system flexibility; however, these robotic systems have been struggling to achieve the holding strength and precision of fully rigid designs [3]. Recent research has explored the use of variable stiffness links in soft, continuum robots for surgery, which contains aspects of both systems by varying the rigidity of the robot [4][5]. This development allows the robot to overcome the strength limitation of soft robotics, by providing a rigid platform when the robot is 'activated'. However, at present, no robots with a reduced number of DOF that can be adaptable to multiple tasks with variable but controllable workspace exist; these robots are a need for the automation of processes and the augmentation of human operator capabilities in confined and remote environments.This research aims to combine, improve, and extend existing research in soft robotics for use in reconfigurable serial arms, producing robots with a reduced number of DOF that can adjust their topology using variable stiffness links, thus being able to perform a range of tasks with a focus on handling and pickand-place assembly operations. Ideal implementations of these systems would be as collaborative robotics in operations that require a reduced size/weight robot with a high DOF performance, namely deep sea and space robotics. These novel manipulators have the possibility of greater flexibility by adapting to different workspaces while keeping the benefits of a lower DOF robotic system, such as weight, size, and control complexity. The proposed robots will be fabricated using serial chains of extrinsic malleable links: A variable stiffness, flexible, continuously bending link which can be repositioned by hand when in a non-rigid state, while holding its position when activated. These malleable links will be connected by revolute joints to be able to perform the operations that can be carried out with traditional robotic arms.