Design, Actuation, and Functionalization of Untethered Soft Magnetic Robots with Life-Like Motions: A Review

Soft robots have demonstrated superior flexibility and functionality than conventional rigid robots. These versatile devices can respond to a wide range of external stimuli (including light, magnetic field, heat, electric field, etc.), and can perform sophisticated tasks. Notably, soft magnetic robots exhibit unparalleled advantages among numerous soft robots (such as untethered control, rapid response, and high safety), and have made remarkable progress in small-scale manipulation tasks and biomedical applications. Despite the promising potential, soft magnetic robots are still in their infancy and require significant advancements in terms of fabrication, design principles, and functional development to be viable for real-world applications. Recent progress shows that bionics can serve as an effective tool for developing soft robots. In light of this, the review is presented with two main goals: (i) exploring how innovative bioinspired strategies can revolutionize the design and actuation of soft magnetic robots to realize various life-like motions; (ii) examining how these bionic systems could benefit practical applications in small-scale solid/liquid manipulation and therapeutic/diagnostic-related biomedical fields

The Problem of Adhesion Methods and Locomotion Mechanism Development for Wall-Climbing Robots

This review considers a problem in the development of mobile robot adhesion methods with vertical surfaces and the appropriate locomotion mechanism design. The evolution of adhesion methods for wall-climbing robots (based on friction, magnetic forces, air pressure, electrostatic adhesion, molecular forces, rheological properties of fluids and their combinations) and their locomotion principles (wheeled, tracked, walking, sliding framed and hybrid) is studied. Wall-climbing robots are classified according to the applications, adhesion methods and locomotion mechanisms. The advantages and disadvantages of various adhesion methods and locomotion mechanisms are analyzed in terms of mobility, noiselessness, autonomy and energy efficiency. Focus is placed on the physical and technical aspects of the adhesion methods and the possibility of combining adhesion and locomotion methods

Wirelessly-Controlled Untethered Piezoelectric Planar Soft Robot Capable of Bidirectional Crawling and Rotation

Electrostatic actuators provide a promising approach to creating soft robotic sheets, due to their flexible form factor, modular integration, and fast response speed. However, their control requires kilo-Volt signals and understanding of complex dynamics resulting from force interactions by on-board and environmental effects. In this work, we demonstrate an untethered planar five-actuator piezoelectric robot powered by batteries and on-board high-voltage circuitry, and controlled through a wireless link. The scalable fabrication approach is based on bonding different functional layers on top of each other (steel foil substrate, actuators, flexible electronics). The robot exhibits a range of controllable motions, including bidirectional crawling (up to ~0.6 cm/s), turning, and in-place rotation (at ~1 degree/s). High-speed videos and control experiments show that the richness of the motion results from the interaction of an asymmetric mass distribution in the robot and the associated dependence of the dynamics on the driving frequency of the piezoelectrics. The robot's speed can reach 6 cm/s with specific payload distribution.Comment: Accepted to the 2023 IEEE International Conference on Robotics and Automation (ICRA

Robotic metamorphosis by origami exoskeletons

Changing the inherent physical capabilities of robots by metamorphosis has been a long-standing goal of engineers. However, this task is challenging because of physical constraints in the robot body, each component of which has a defined functionality. To date, self-reconfiguring robots have limitations in their on-site extensibility because of the large scale of today’s unit modules and the complex administration of their coordination, which relies heavily on on-board electronic components. We present an approach to extending and changing the capabilities of a robot by enabling metamorphosis using self-folding origami “exoskeletons.” We show how a cubical magnet “robot” can be remotely moved using a controllable magnetic field and hierarchically develop different morphologies by interfacing with different origami exoskeletons. Activated by heat, each exoskeleton is self-folded from a rectangular sheet, extending the capabilities of the initial robot, such as enabling the manipulation of objects or locomotion on the ground, water, or air. Activated by water, the exoskeletons can be removed and are interchangeable. Thus, the system represents an end-to-end (re)cycle. We also present several robot and exoskeleton designs, devices, and experiments with robot metamorphosis using exoskeletons

Self-propelled Bouncing Spherical Robot

25th Annual Denman Undergraduate Research Forum Finalist Second PlaceMost robots that can travel on the ground are either traditional wheeled robots or legged robots. Exploring non-traditional novel robots may provide new solutions for locomotion not previously examined. Currently, self-rolling spherical robots have been designed and manufactured for hobbies, entertainment, or military uses. Similarly, various researchers have built legged robots that walk and run. Our objective in this research project was to design, build, and control a self-propelled bouncing and rolling spherical robot. While some self-bouncing wheeled robots have been built as toys, the self-bouncing spherical robot (one that looks like a ball) remains largely not explored. No one has produced a robot that can bounce continuously and can be steered without any external device to assist its movement. To achieve this goal, we plan to prototype up to three different mechanisms for bouncing. Each prototype would go through brainstorming, computer-aided design and simulation (of the bouncing), initial build, redesign, second build, and final analysis. We follow the classic design cycle: observe, ideation, prototype, and testing. We will also perform dynamic analyses of the robot to improve the design. This thesis reports on current progress towards these goals: we have designed and fabricated (and iterated) on a simple prototype bouncing ball, based on a spinning internal mass; we have performed some 2D and 3D simulations of the spinning mechanism that shows promise for the mechanism to produce persistent bouncing. Future work will consist of improving the current prototype, matching the computer simulations quantitatively to the prototype, performing design optimization and trajectory optimizations for optimal control, exploring other designs closer to hopping robots, and finally, building the ability to control and steer the robot.The Ohio State University Second-year Transformational Experience ProgramThe Ohio State University College of EngineeringNo embargoAcademic Major: Mechanical Engineerin

Advances in Bio-Inspired Robots

This book covers three major topics, specifically Biomimetic Robot Design, Mechanical System Design from Bio-Inspiration, and Bio-Inspired Analysis on A Mechanical System. The Biomimetic Robot Design part introduces research on flexible jumping robots, snake robots, and small flying robots, while the Mechanical System Design from Bio-Inspiration part introduces Bioinspired Divide-and-Conquer Design Methodology, Modular Cable-Driven Human-Like Robotic Arm andWall-Climbing Robot. Finally, in the Bio-Inspired Analysis on A Mechanical System part, research contents on the control strategy of Surgical Assistant Robot, modeling of Underwater Thruster, and optimization of Humanoid Robot are introduced

Exploiting the Nonlinear Stiffness of Origami Folding to Enhance Robotic Jumping Performance

This research investigates the effects of using origami folding techniques to develop a nonlinear jumping mechanism with optimized dynamic performance. A previous theoretical investigation has shown the benefits of using a nonlinear spring element compared to a linear spring for improving the dynamic performance of a jumper. This study sets out to experimentally verify the effectiveness of utilizing nonlinear stiffness to achieve optimized jumping performance. The Tachi-Miura Polyhedron (TMP) origami structure is used as the nonlinear energy-storage element connecting two end-point masses. The TMP bellow exhibits a “strain-softening” nonlinear force-displacement behavior resulting in an increased energy storage compared to a linear spring. The geometric parameters of the structure are optimized to improve air-time and maximum jumping height. An additional TMP structure was designed to exhibit a close-to-linear force-displacement response to serve as the representative linear spring element. A critical challenge in this study is to minimize the hysteresis and energy loss of TMP during its compression stage before jumping. To this end, plastically annealed lamina emergent origami (PALEO) concept is used to modify the creases of the structure in order to reduce hysteresis during the compression cycle. PALEO works by increasing the folding limit before plastic deformation occurs, thus improving the energy retention of the structure. Steel shim stock are secured to the facets of the TMP structure to serve as end-point masses, and the air-time and jumping height of both structures are measured and compared. The nonlinear TMP structure achieves roughly 9% improvement in air-time and a 12% improvement in jumping height when compared to the linear TMP structure. These results validate the theoretical benefits of utilizing nonlinear spring elements in jumping mechanisms and can lead to improved performance in dynamic systems which rely on springs as a method of energy storage and can lead to emergence of a new generation of more efficient jumping mechanisms with optimized performance in the future