Shen Donghua, Zhang Qi, Han Yali, Tu Chunlei, Wang Xingsong
School of Mechanical Engineering, Nanjing Institute of Technology, Nanjing, China.
School of Automation, Nanjing University of Information Science and Technology, Nanjing, China.
Soft Robot. 2023 Oct;10(5):1015-1027. doi: 10.1089/soro.2022.0179. Epub 2023 May 4.
Continuum robots have the advantages of agility and adaptability. However, existing continuum robots have limitations of low stiffness and complex motion modes, and the existing variable stiffness methods cannot achieve a wide range of stiffness changes and fast switching stiffness simultaneously. A continuum robot structure, switching stiffness method, and motion principle are proposed in this article. The continuum robot is made up of three segments connected in series. Each segment comprises multiple spherical joints connected in series, and the joints can be locked by their respective airbag. A valve controls each airbag, quickly switching the segment between rigidity and flexibility. The motion of the segments is driven by three cables that run through the robot. The segment steers only when it is unlocked. When a segment becomes locked, it acts as a rigid body. As a result, by locking and unlocking each segment in sequence, the cables can alternately drive all the segments. The stiffness variation and movement of the continuum robot were tested. The segment's stiffness varies from 36.89 to 1300.95 N/m and the stiffness switching time is 0.25-0.48 s. The time-sharing control mode of segment stiffness and motion is validated by establishing a specific test platform and a mathematical model. The continuum robot's flexibility is demonstrated by controlling the fast bending of different segments sequentially.
连续体机器人具有灵活性和适应性的优点。然而，现有的连续体机器人存在刚度低和运动模式复杂的局限性，并且现有的可变刚度方法无法同时实现大范围的刚度变化和快速的刚度切换。本文提出了一种连续体机器人结构、切换刚度方法和运动原理。该连续体机器人由三个串联的节段组成。每个节段包括多个串联的球形关节，并且关节可以通过各自的气囊锁定。一个阀门控制每个气囊，快速在刚度和灵活性之间切换节段。节段的运动由三根穿过机器人的缆绳驱动。节段仅在解锁时转向。当一个节段锁定时，它就充当刚体。因此，通过依次锁定和解锁每个节段，缆绳可以交替驱动所有节段。对连续体机器人的刚度变化和运动进行了测试。节段的刚度在36.89至1300.95N/m之间变化，刚度切换时间为0.25 - 0.48s。通过建立特定的测试平台和数学模型，验证了节段刚度和运动的分时控制模式。通过依次控制不同节段的快速弯曲，展示了连续体机器人的灵活性。
