Our JRM Paper with Iwamoto Sensei Has Been Published
umedachi@shinshu-u.ac.jp
We are pleased to announce that our joint research with Assistant Prof. Noriyasu Iwamoto (Shinshu University) and Masaru Miyajima has been published in the international journal Journal of Robotics and Mechatronics (JRM).
Citation: “Variable-Corner Robotic Surfaces with Minimal Area and Their Kinematics.” Masaru Miyajima, Takuya Umedachi, Noriyasu Iwamoto, Journal of Robotics and Mechatronics (JRM), 37(1): 143–152, Published Feb. 20, 2025. DOI: 10.20965/jrm.2025.p0143 ( Open access).
Summary of “Variable-Corner Robotic Surfaces with Minimal Area and Their Kinematics”
This study proposes a robotic surface whose boundary can change the number of corners and analyzes its kinematics.
- Background. Conventional robotic surfaces typically keep the number and positions of boundary corners fixed in the undeformed state.
- Proposal. We realize a boundary with a variable number of corners by combining a ring-shaped actuator—constructed from three types of bending elements—with a soap-film membrane.
- Kinematic formulation. We develop both forward kinematics (FK) and inverse kinematics (IK) tailored to such variable-corner surfaces. The boundary is modeled as a minimal surface (a shape of minimal area), and the interior geometry is computed by solving the Laplace equation, forming the basis of the kinematic model.
- IK algorithm. We introduce a method that adjusts the internal pressure of the actuators so that designated control points reach their target positions.
- Results. Simulations demonstrate feasible shape transitions and boundary-corner changes under the proposed FK/IK framework.
- Applicability. The approach can be extended to soft-robotic surfaces made from prestretched silicone rubber or fabrics, offering a new pathway for shape control of robotic skins/surfaces.
