Multimodal pipe-climbing robot with origami clutches and soft modular legs

In nature, climbing trees and pipes of varying diameters or even navigating inside of hollow pipes and tree holes is easy for some climbing animals and insects. However, today's pipe-climbing robots, which are important for automatically conducting periodic inspections and maintenance of pipelines to save time and keep humans away from hazardous environments, are designed mainly for a specific task, limiting their adaptability to different working scenarios and further implementation in real-life. In this paper, we propose a pipe-climbing robot with a soft linear actuator for bioinspired propulsion, two origami clutches to realize multi-degrees-of-freedom (DoF) motion and two pairs of soft modular legs for multimodal climbing. Design, modeling and experimental validation of the origami clutch are introduced in detail. Preliminary experimental results show that we can achieve a stroke of up to 289.6% and a maximum 45 degrees bending angle on the soft linear actuator by regulating the air pressure inside the soft actuator and origami clutches. Additionally, by choosing the leg-type, three climbing modes, including out-pipe versatile mode, out-pipe high-force mode and in-pipe mode can be realized for particular working scenarios. A prototype climbing robot demonstrates that in out-pipe versatile mode, the robot can climb on the exterior of pipes made of various materials including PVC, rubber and metal with diameters ranging from 105 to 117 mm. In the out-pipe high-force mode, the climber can navigate along a specific pipe carrying maximum 675 g external load at the top or 200 g hanging from the bottom, as well as keeping functional without failure under static loads as high as 1968 g. In the in-pipe mode, the robot is able to travel inside pipes. This research might bridge the design gap between in-pipe and out-pipe climbing robots while offering an alternative option for soft robots to execute multi-DoF motion.

Modular soft pneumatic actuator system design for compliance matching

Matthew Aaron Robertson

The future of robotics is personal. Never before has technology been as pervasive as it is today, with advanced mobile electronics hardware and multi-level network connectivity pushing âsmartâ devices deeper into our daily lives through home automation systems, virtual assistants, and wearable activity monitoring. As the suite of personal technology around us continues to grow in this way, augmenting and offloading the burden of routine activities of daily living, the notion that this trend will extend to robotics seems inevitable. Transitioning robots from their current principal domain of industrial factory settings to domestic, workplace, or public environments is not simply a matter of relocation or reprogramming, however. The key differences between âtraditionalâ types of robots and those which would best serve personal, proximal, human interactive applications demand a new approach to their design. Chief among these are requirements for safety, adaptability, reliability, reconfigurability, and to a more practical extent, usability. These properties frame the context and objectives of my thesis work, which seeks to provide solutions and answers to not only how these features might be achieved in personal robotic systems, but as well what benefits they can afford. I approach the investigation of these questions from a perspective of compliance matching of hardware systems to their applications, by providing methods to achieve mechanical attributes complimentary to their environment and end-use. These features are fundamental to the burgeoning field of Soft Robotics, wherein flexible, compliant materials are used as the basis for the structure, actuation, sensing, and control of complete robotic systems. Combined with pressurized air as a power source, soft pneumatic actuator (SPA) based systems offers new and novel methods of exploiting the intrinsic compliance of soft material components in robotic systems. While this strategy seems to answer many of the needs for human-safe robotic applications, it also brings new questions and challenges: What are the needs and applications personal robots may best serve? Are soft pneumatic actuators capable of these tasks, or âusefulâ work output and performance? How can SPA based systems be applied to provide complex functionality needed for operation in diverse, real-world environments? What are the theoretical and practical challenges in implementing scalable, multiple degrees of freedom systems, and how can they be overcome? I present solutions to these problems in my thesis work, elucidated through scientific design, testing and evaluation of robotic prototypes which leverage and demonstrate three key features: 1) Intrinsic compliance: provided by passive elastic and flexible component material properties, 2) Extrinsic compliance: rendered through high number of independent, controllable degrees of freedom, and 3) Complementary design: exhibited by modular, plug and play architectures which combine both attributes to achieve compliant systems. Through these core projects and others listed below I have been engaged in soft robotic technology, its application, and solutions to the challenges which are critical to providing a path forward within the soft robotics field, as well as for the future of personal robotics as a whole toward creating a better society.

EPFL2019

Development of Essential Components for Soft Wearable Technologies

Amir Firouzeh

The rising demand for safe human-robot interaction in daily tasks has motivated significant research effort in the robotics field towards compliant and conformable robots, capable of replicating complex human movements in applications such as wearable rehabilitative devices and haptic interfaces. Novel manufacturing, actuation, and sensing technologies contributed significantly to this field by providing design and manufacturing frameworks for inherently compliant robots. Although promising, these technologies are still in the early stages of development and base research for refining their design, improving their performance, and defining design criteria is still required for these technologies to reach their full potential. In this thesis, some of the main challenges hindering the effective application of robotics in wearable devices are tackled. We propose the robotic origami (robogami) framework with multiple but finite degrees of freedom (DoFs) for soft wearable devices. Robogamis are low profile robots that provide conformity and compliance with their multiple DoFs driven by soft actuation methods. The finite DoFs in these robots enable better prediction and planning of their motion while highly customizable joint designs, thanks to the layer-by-layer manufacturing and the precise quasi-2D fabrication processes, allows the multiple DoFs to be embedded to achieve the required level of conformity. The main contributions of this thesis are: -Study of the robogami framework as a design platform for soft robots with programmable reconfiguration and compliance. -Design and validation of actuation solutions based on smart materials for independent actuation of robogami joints. -Adoption of the smart materials' variable mechanical properties to adjust the stiffness of robogami joints and the overall compliance of the robot. -Development of customized sensing methods to measure robogami joint angles and stretchable sensors based on the same principles to measure body movements. We believe that these contributions facilitate some of the main challenges for the effective application of robogamis in wearable devices for safe and yet capable interaction with humans. The highly customizable components can also be used in design frameworks other than robogamis and other applications where compliance and conformity are required.

EPFL2017

Development and control of interactive reconfigurable robotic systems

Jian-Lin Huang

While reconfigurable robots provide a new promising approach for interactive systems, the complexity of distributed actuation/sensing systems, coupled kinematics and desired functionalities also bring new challenges and questions both in control design and hardware development: What design approaches enable direct human-robot interactions to address the morphological transformations and constraints of multi-DoF distributed activated robotic system? How to implement in-situ, multi-stage, programmable, and controllable actuation for the desired range of motion and functionalities? How to design multi-DoF robotic systems and needed for operation in distinct, real-world applications? These challenges and research questions formulate the objective and framework of my thesis. Namely, I explore for the solutions to provide methodologies for not only building the hardware for reconfigurable interactive systems but also investigating the control algorithm considering human-in-the-loop and evaluating the effectiveness of the integrated system with different application scenarios. In order to address the challenges associated with the development of reconfigurable robotic systems for human interactions, I first outline the concept of an interactive interface between humans and robots. I study the design methods for intuitively and dynamically controlling multi-DoF reconfigurable systems and algorithms for integrating mechanical characteristics of the core robotic components. Then, we investigate the design space and limitation of gesture-based multi-modalities interactions for further exploring the controllability, scalability, and versatility in functions for reconfigurable robotic systems. To realize the reconfigurable interactive robotic system, the design, capability, and limitation of the hardware system need to be established and evaluated. One of my research goals is to take the advantage of current non-conventional manufacturing technologies and materials as well as overcome their limitations. I study and develop compact actuators and unique transmission mechanisms inspired by origami patterns that can be integrated with multi-DoF robotic systems. I start with the design, model, and experimental validation of core functional components. Then, we investigate the fabrication process which has an additive manufactured structure with subtractive manufactured functional components integrated for compact, light-weight, and distributed activated mechanisms. Lastly, I propose the strategies for configuring and controlling the functional components to achieve functionalities like multi-DoF distributed actuation, self-assembly, and tunable stiffness. The achievable functionalities are further examined with several application scenarios. The main contributions of this thesis are: Development of interactive control interface for reconfigurable robotic systems Design and validation of distributed actuation solution and transmission mechanisms for compact multi-DoF robotic systems Study the synergy of additive manufacturing techniques and smart materials for achieving customizable functionalities and overcoming the limitation for conventional robotic systems

EPFL2021