66 research outputs found
Novel Locomotion Methods in Magnetic Actuation and Pipe Inspection
There is much room for improvement in tube network inspections of jet aircraft. Often, these inspections are incomplete and inconsistent. In this paper, we develop a Modular Robotic Inspection System (MoRIS) for jet aircraft tube networks and a corresponding kinematic model. MoRIS consists of a Base Station for user control and communication, and robotic Vertebrae for accessing and inspecting the network. The presented and tested design of MoRIS can travel up to 9 feet in a tube network. The Vertebrae can navigate in all orientations, including smooth vertical tubes. The design is optimized for nominal 1.5 outside diameter tubes. We developed a model of the Locomotion Vertebra in a tube. We defined the model\u27s coordinate system and its generalized coordinates. We studied the configuration space of the robot, which includes all possible orientations of the Locomotion Vertebra. We derived the expression for the elastic potential energy of the Vertebra\u27s suspensions and minimized it to find the natural settling orientation of the robot. We further explore the effect of the tractive wheel\u27s velocity constraint on locomotion dynamics. Finally, we develop a general model for aircraft tube networks and for a taut tether.
Stabilizing bipedal walkers is a engineering target throughout the research community. In this paper, we develop an impulsively actuated walking robot. Through the use of magnetic actuation, for the first time, pure impulsive actuation has been achieved in bipedal walkers. In studying this locomotion technique, we built the world\u27s smallest walker: Big Foot. A dynamical model was developed for Big Foot. A Heel Strike and a Constant Pulse Wave Actuation Schemes were selected for testing. The schemes were validated through simulations and experiments. We showed that there exists two regimes for impulsive actuation. There is a regime for impact-like actuation and a regime for longer duration impulsive actuation
Models for reinforcement learning and design of a soft robot inspired by Drosophila larvae
Designs for robots are often inspired by animals, as they are designed mimicking animals’
mechanics, motions, behaviours and learning. The Drosophila, known as the
fruit fly, is a well-studied model animal. In this thesis, the Drosophila larva is studied
and the results are applied to robots. More specifically: a part of the Drosophila larva’s
neural circuit for operant learning is modelled, based on which a synaptic plasticity
model and a neural circuit model for operant learning, as well as a dynamic neural network
for robot reinforcement learning, are developed; then Drosophila larva’s motor
system for locomotion is studied, and based on it a soft robot system is designed.
Operant learning is a concept similar to reinforcement learning in computer science,
i.e. learning by reward or punishment for behaviour. Experiments have shown
that a wide range of animals is capable of operant learning, including animal with only
a few neurons, such as Drosophila. The fact implies that operant learning can establish
without a large number of neurons. With it as an assumption, the structure and dynamics
of synapses are investigated, and a synaptic plasticity model is proposed. The
model includes nonlinear dynamics of synapses, especially receptor trafficking which
affects synaptic strength. Tests of this model show it can enable operant learning at the
neuron level and apply to a broad range of NNs, including feedforward, recurrent and
spiking NNs.
The mushroom body is a learning centre of the insect brain known and modelled
for associative learning, but not yet for operant learning. To investigate whether it participates
in operant learning, Drosophila larvae are studied with a transgenic tool by
my collaborators. Based on the experiment and the results, a mushroom body model
capable of operant learning is modelled. The proposed neural circuit model can reproduce
the operant learning of the turning behaviour of Drosophila larvae.
Then the synaptic plasticity model is simplified for robot learning. With the simplified
model, a recurrent neural network with internal neural dynamics can learn to
control a planar bipedal robot in a benchmark reinforcement learning task which is
called bipedal walker by OpenAI. Benefiting efficiency in parameter space exploration
instead of action space exploration, it is the first known solution to the task with reinforcement
learning approaches.
Although existing pneumatic soft robots can have multiple muscles embedded in
a component, it is far less than the muscles in the Drosophila larva, which are well-organised
in a tiny space. A soft robot system is developed based on the muscle pattern
of the Drosophila larva, to explore the possibility to embed a high density of muscles
in a limited space. Three versions of the body wall with pneumatic muscles mimicking
the muscle pattern are designed. A pneumatic control system and embedded control
system are also developed for controlling the robot. With a bioinspired body wall will
a large number of muscles, the robot performs lifelike motions in experiments
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
An Overview of Legged Robots
The objective of this paper is to present the evolution and the state-of-theart in the area of legged locomotion systems. In a first phase different possibilities for mobile robots are discussed, namely the case of artificial legged locomotion systems, while emphasizing their advantages and limitations. In a second phase an historical overview of the evolution of these systems is presented, bearing in mind several particular cases often considered as milestones on the technological and scientific progress. After this historical timeline, some of the present day systems are examined and their performance is analyzed. In a third phase are pointed out the major areas for research and development that are presently being followed in the construction of legged robots. Finally, some of the problems still unsolved, that remain defying robotics research, are also addressed.N/
Modeling, analysis and control of robot-object nonsmooth underactuated Lagrangian systems: A tutorial overview and perspectives
International audienceSo-called robot-object Lagrangian systems consist of a class of nonsmooth underactuated complementarity Lagrangian systems, with a specific structure: an "object" and a "robot". Only the robot is actuated. The object dynamics can thus be controlled only through the action of the contact Lagrange multipliers, which represent the interaction forces between the robot and the object. Juggling, walking, running, hopping machines, robotic systems that manipulate objects, tapping, pushing systems, kinematic chains with joint clearance, crawling, climbing robots, some cable-driven manipulators, and some circuits with set-valued nonsmooth components, belong this class. This article aims at presenting their main features, then many application examples which belong to the robot-object class, then reviewing the main tools and control strategies which have been proposed in the Automatic Control and in the Robotics literature. Some comments and open issues conclude the article
Locomation strategies for amphibious robots-a review
In the past two decades, unmanned amphibious robots have proven the most promising and efficient systems ranging from scientific, military, and commercial applications. The applications like monitoring, surveillance, reconnaissance, and military combat operations require platforms to maneuver on challenging, complex, rugged terrains and diverse environments. The recent technological advancements and development in aquatic robotics and mobile robotics have facilitated a more agile, robust, and efficient amphibious robots maneuvering in multiple environments and various terrain profiles. Amphibious robot
locomotion inspired by nature, such as amphibians, offers augmented flexibility, improved adaptability, and
higher mobility over terrestrial, aquatic, and aerial mediums. In this review, amphibious robots' locomotion
mechanism designed and developed previously are consolidated, systematically The review also analyzes
the literature on amphibious robot highlighting the limitations, open research areas, recent key development
in this research field. Further development and contributions to amphibious robot locomotion, actuation, and
control can be utilized to perform specific missions in sophisticated environments, where tasks are unsafe
or hardly feasible for the divers or traditional aquatic and terrestrial robots
Climbing and Walking Robots
With the advancement of technology, new exciting approaches enable us to render mobile robotic systems more versatile, robust and cost-efficient. Some researchers combine climbing and walking techniques with a modular approach, a reconfigurable approach, or a swarm approach to realize novel prototypes as flexible mobile robotic platforms featuring all necessary locomotion capabilities. The purpose of this book is to provide an overview of the latest wide-range achievements in climbing and walking robotic technology to researchers, scientists, and engineers throughout the world. Different aspects including control simulation, locomotion realization, methodology, and system integration are presented from the scientific and from the technical point of view. This book consists of two main parts, one dealing with walking robots, the second with climbing robots. The content is also grouped by theoretical research and applicative realization. Every chapter offers a considerable amount of interesting and useful information
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