Morphological change in peristaltic crawling motion of a narrow pipe inspection
robot inspired by earthworm’s locomotion
M. Kamata, S. Yamazaki, Y. Tanise, Y. Yamada and T. Nakamura
Precision Mechanics, chuo University, tokyo, Japan
ABSTRACT
Infrastructure pipes require inspection in order to prevent accidents. However, it is diffilt to inspect a1-in-diameter gas pipe because it is long, narrow and complicated. Therefore, an earthworm-type robot was developed to inspect this 1-in pipe. The robot moved by peristaltic crawling with pneumatic artifiial muscles and displayed its suitability as a 1-in pipe inspection robot in experiments. However, its speed was extremely slow to be practically utilized. A major cause for this is the small distance covered in a single motion of the robot. Therefore, in this study, we developed an axial extension actuator to increase the moving distance of the robot in a single motion. Furthermore, we installed this new actuator on our robot and made it possible for the robot to change the morphological motion in peristaltic crawling. The experiments with straight and elbow pipes ascertained the
importance of morphological change in peristaltic crawling for increasing the speed of the robot. Moreover, in a continuous elbow pipe, the velocity of the proposed robot was 5.5 mm/s, which is 1.3 times faster than that of the conventional robot. Consequently, we confimed that the speed of the proposed robot was suffiently fast for inspecting a1-in pipe.
KEYWORDS
Pipe inspection; artifiial muscle; earthworm robot
Morphological computation-based c ontrol of a modular, p neumatically driven, soft robotic arm
M. Edera, F. Hischb and H. Hauserc,d
aArtificial Intelligence Laboratory, Institute for Informatics, University of Zurich, Zurich, Switzerland; bInstitut für Informatik, Technische Universität München, Munich, Germany; cDepartment of Engineering Mathematics, University of Bristol, Bristol, UK; dBristol Robotics Laboratory, Bristol, UK
ABSTRACT
The dynamics of soft robotic bodies are typically complex and exhibit nonlinearities and a high dimensional state space. As a result, such systems are difficult to model and, therefore, hard to control. In this work, we use a model free approach by employing the concept of morphological computation, which understands the complexity of the dynamics of such bodies as potential computational resources that can be exploited, for example, for control. The validity of this approach has been
previously demonstrated in a number of simulations as well on a number of simple soft robotic platforms. However, this work takes the approach a significant step further by implementing it on a highly complex pneumatically driven robotic arm consisting of multiple modular segments, bringing the morphological computation-based control approach closer to real industrial applications. We demonstrate that various oval shaped end point trajectories can be learned and be reproduced consistently in a remarkably robust fashion. The presented morphological computation setup needs no model of the highly complex robot. Moreover, by exploiting the seemingly unbeneficial complex dynamics as a computational resource, the learning task to implement a nonlinear and dynamic control can be reduced to simple linear regression.
KEYWORDS
Morphological computation; soft robotics; compliant robot arm; model-free control; embodiment
Morphological computation i n haptic sensation and interaction: from nature to r o b o t i c s
Julius E. Berntha, Van Anh Hob and Hongbin Liua
aDepartment of Informatics, King’s College London, London, UK; bSchool of Materials Science, Japan Advanced Institute of Science and Technology (JAIST), Nomi, Japan
ABSTRACT
Haptics, or the sense of touch, has played an important role in enhancing the versatility and capabilities of robots. Tasks involving unstructured or changing environments can significantly benefit from haptic sensation. The requirements of such sensing systems can be complex, however. Many designers have succeeded in using the morphological properties of the sensors themselves,
such as geometry or material properties, to replicate or replace the functions of traditional computer control, reducing the burden on the central controller. This concept is generally referred to as morphological computation or embodied intelligence in the literature. This review will investigate the role morphological computation has played in haptic sensing and discuss potential future avenues of research. In the review, the concept of morphological computation will first be more rigorously defined. This is followed by an investigation into how nature has solved the problem of touch and a discussion of how such morphological principles could inspire design of similar systems in robotics. The state of haptic systems for display, sensing and interaction that utilise morphological computation is then surveyed. Finally, approaches to future research on morphological computation in haptics are discussed as well as some of the major challenges in this field.
KEYWORDS
Haptics; tactile sensing; morphological computation; biologically inspired robots and systems; soft materials
Suitable confiurations for pneumatic soft sheet actuator to generate traveling
waves
Masahiro Watanabe and Hideyuki Tsukagoshi
department of Mechanical and control engineering, tokyo institute of technology, tokyo, Japan
ABSTRACT
This paper presents suitable confiurations for a pneumatic soft sheet actuator capable of moving by traveling waves. Inspired by the locomotion of snails and slugs using pedal foot generating traveling waves, we challenge to develop a pneumatic sheet type actuator named Wavy-sheet, aiming to make it move even on a fragile environment which the wheel-type robots are hard to cross
over. To design the suitable confiuration to fulfil the above purpose, fist, we derive combinations of realizable waveform patterns from a mathematical point of view and examine the characteristics of the waves. Next, after a couple of desired confiurations are selected from the aspects of velocity and payload, their prototypes are fabricated. Finally, to verify the validity of our consideration, the experiments are conducted, and the most suitable confiuration for the proposed actuator is determined.
KEYWORDS
Word; pneumatic actuator; traveling waves; soft robot; biomimetics; gastropods
