To create fully-soft robots, fully-soft actuators are needed. Currently, soft rotary actuator topologies described in the literature exhibit low rotational speeds, which limit their applicability. In this work, we describe a novel, fully-soft synchronous rotary electromagnetic actuator and soft magnetic contact switch sensor concept. In this study, the actuator is constructed using gallium indium liquid metal conductors, compliant permanent magnetic composites, carbon black powders, and flexible polymers. The actuator also operates using low voltages (<20 V, ≤10 A), has a bandwidth of 10 Hz, a stall torque of 2.5-3 mN·m, and no-load speed of up to 4000 rpm. These values show that the actuator rotates at over two orders-of-magnitude higher speed with at least one order-of-magnitude higher output power than previously developed soft rotary actuators. This unique soft rotary motor is operated in a manner similar to traditional hard motors, but is also able to stretch and deform to enable new soft robot functions. To demonstrate fully-soft actuator application concepts, the motor is incorporated into a fully-soft air blower, fully-soft underwater propulsion system, fully-soft water pump, and squeeze-based sensor for a fully-soft fan. Hybrid hard and soft applications were also tested, including a geared robotic car, pneumatic actuator, and hydraulic pump. Overall, this work demonstrates how the fully-soft rotary electromagnetic actuator can bridge the gap between the capabilities of traditional hard motors and novel soft actuator concepts.

中文翻译：

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用于同步旋转运动的软电磁电机和软磁传感器。

要创建全软机器人，需要全软执行器。目前，文献中描述的软旋转致动器拓扑表现出低旋转速度，这限制了它们的适用性。在这项工作中，我们描述了一种新颖的全软同步旋转电磁执行器和软磁接触开关传感器概念。在这项研究中，执行器采用镓铟液态金属导体、顺应性永磁复合材料、炭黑粉末和柔性聚合物构建。该执行器还可以使用低电压（<20 V，≤10 A）运行，带宽为 10 Hz，失速扭矩为 2.5-3 mN·m，空载速度高达 4000 rpm。这些值表明，与之前开发的软旋转执行器相比，执行器的旋转速度高出两个数量级以上，输出功率至少高出一个数量级。这种独特的软旋转电机的运行方式与传统硬电机类似，但也能够拉伸和变形以实现新的软机器人功能。为了演示全软执行器应用概念，电机被集成到全软鼓风机、全软水下推进系统、全软水泵和用于全软风扇的基于挤压的传感器中。还测试了混合硬和软应用，包括齿轮机器人汽车、气动执行器和液压泵。总的来说，这项工作展示了全软旋转电磁执行器如何弥合传统硬电机和新颖软执行器概念之间的差距。