Biomechatronics

Marko B. Popovic

• Publisher: Academic Press
• Year: 2019
• ISBN:
  9780128130414
• Topic: Technology & Engineering
• Subtopic: Robotics
• Index: Technology & Engineering

Biomechatronics is rapidly becoming one of the most influential and innovative research directions defining the 21st century. Biomechatronics provides a complete and up-to-date account of this advanced subject at the university textbook level. Each chapter is co-authored by top experts led by Professor Marko B. Popovic, researcher and educator at the forefront of advancements in this fascinating field. Beginning with an introduction to biomechatronics and its historical background, this book delves into the most groundbreaking recent developments in a wide variety of subjects, such as artificial organs and tissues, prosthetic limbs, neural interfaces, orthotic systems, wearable systems for physical augmentation, physical therapy and rehabilitation, robotic surgery, natural and synthetic actuators, sensors, and control systems. A number of practice problems and solutions are provided at the end of the book. Two years in the making, the book Biomechatronics is a result of dedicated work of a team of close to thirty contributors from all across the globe including top researchers and educators from the USA (Popovic, Lamkin-Kennard, Sinyukov, Troy, Goodworth, Johnson, Kaipa, Onal, Bowers, Djuric, Fischer, Ji, Jovanovic, Luo, Padir, Tetreault), Japan (Tashiro, Iramina, Ohta, Terasawa), Sweden (Boyraz), Turkey (Arslan, Karabulut, Ortes), Germany (Beckerle, Willwacher), New Zealand (Liarokapis), and Switzerland (Dobrev).

• The only biomechatronics textbook written especially for students at a university level
• Ideal for undergraduate and graduate students and researchers in the biomechatronics, biomechanics, robotics, and biomedical engineering fields
• Provides an overview of state-of-the-art science and technology of modern day biomechatronics, introduced by the leading experts in this fascinating field

1

Introduction

Marko B. Popovic Worcester Polytechnic Institute, Worcester, MA, United States

Abstract

Biomechatronics holds a promise to be one of the most influential innovative research directions defining the 21st century. Here, a notion of biomechatronics is defined and various topics encompassed by this “crown” of science and technology are briefly reviewed in the context of material presented in this book.

Keywords

Biomechatronics; Biological; Mechatronics; Robotics; Bionic

Born at the turn of the 21st century, the word biomechatronics refers to an interdisciplinary field that closely merges biological and mechatronics systems.

Here, mechatronics refers to technology combining electronics and mechanical engineering according to its dictionary definition.

The word biomechatronics, also initially written as bio-mechatronics, has been in use since the late 1990s. Since then, numerous authors have attempted to provide a concise and accurate definition that would most appropriately describe this popular field. Unfortunately, the majority of them failed to some extent either because they artificially limited its notion to only a very specialized subfield, typically, closely related to their own research theme or topic, or because they regrettably missed to fully recognize a fine ambiguity in the level of unification of biological and synthetic systems, here, specifically mechatronics systems.

For example, consider a human driving a car. Is that a biomechatronic system? Probably not, if the car is just an old-fashioned 20th-century car, a machine which is merely mechanically operated by human driver. And probably yes, if the car is an advanced 21st-century car which interfaces more closely with human driver and directly affects the process of driving through a controlled feedback loop. Imagine that this car can sense its environment, own state, and state of the human driver. It can understand user intent, has different levels of communication with a user, and can provide automatic breaking or steering when necessary. For example, interior car cameras can decipher user's attention and direction in which the driver is glimpsing at, based on the orientation of the driver's head and location of irises and eye pupils. Moreover, tremor in operation of steering wheel or gas pedal can be removed or even car seat and specifically neck support could change stiffness levels based on vibration levels introduced by different road conditions. Clearly, this is a prime example of biomechatronic system and human-machine merging.

Hence, biomechatronics is quite a wide field covering every system that closely relates biological and mechatronics system within a functionally unified entity.

First wave of usage of this word was rather naturally focused on advanced human prosthetic and brace technologies, specifically robots that are either attached to or wrapped around the human body as well as on advanced human rehabilitation technologies. However, biomechatronic practices have also been advanced, as it is probably less known, in the context of robotics and automation biotechnologies for bioproduction and control in agriculture, food processing, and pharmaceutical industries.

Due to its interdisciplinary nature, wide range of applicability, and impact that it creates, biomechatronics holds a promise to be one of the most influential innovative research directions defining the 21st century.

Due to the expertise of its authors, this book is mainly focused on human-centered biomechatronics. All chapters addressing concrete examples of biomechatronic system have a human directly looped in the system. The one exception toward the end of this book is Chapter 17 on bioinspired robots that only indirectly deals with human beings and animals; either through biologically motivated design or through co-robot (collaborative robot) concept. There is also some mention in the concluding Chapter 18 of assistive systems for animals.

This choice of human-centered content certainly does not imply that other areas of biomechatronics are of any lesser value. It is just the available knowledge and bandwidth of this team of authors which lead to the choice of material covered in this book. For readers with more interest, for example, in biomechatronic design in biotechnology one may review the book by Carl-Fredrik Mandenius and Mats Bjorkman published by Willey in 2011 [1].

Kinematics and dynamics relevant for manipulation, locomotion, postural balance, and propulsion in fluids are addressed in Chapter 2. Standard terminology is introduced and several conventional computational and problem-solving techniques are reviewed. These theoretical “tools” and methods are frequently utilized in the Biomechatronics research. However, as a drawback, Chapter 2 can be easily expanded to cover the entire book due to the nature of its content, and hence material presented here is somewhat condensed and limited in scope. Readers who find this material too difficult to follow but are still motivated to learn more on these topics may want to review a well-written book by John J. Craig published by Pearson/Prentice-Hall in 2005 [2]. Actually, a whole variety of textbooks and online video lectures exist that readers might find handy [3–12]. Still further, readers may also opt to completely skip Chapter 2 and without much consequence and overdue focus their attention on other materials presented in this book. When needed, reader may clearly return to Chapter 2 for clarification or look into one of the many useful references on these topics.

Review and comparison of biological and synthetic organismal building blocks in terms of passive material properties, actuation, sensing, and control/intelligence is a grand theme of Chapters 3–5. Chapter 3 discusses biological and synthetic actuators. Chapter 4 addresses biological and synthetic sensors. Chapter 5 focuses on biological and synthetic control/intelligence. All these are quite relevant in the context of biomechatronics research. In order to decide how best to interface with biological system one should clearly know a lot on biological system including its building block elements. Moreover, that knowledge can also serve as a good inspiration to engineer high fidelity synthetic counterparts. Still further, it is always good to have a “rich menu,” that is, multiple options on the table in terms of synthetic elements; different problems may require different approaches and corresponding components. Finally, it is a quite intellectually rewarding experience to compare living and engineered systems and their building block elements.

Majority of books focused on robotics follow this actuator-sensor-control organization with good reason. After all, robot is nothing else than synthetic organism. According to “Biomechanics and Robotics” book [13]: “Robotics is the branch of Science, Technology and Art that deals with robots, that is, artificial ‘organisms’ that convey lifelike appearance by physical actions (movements, etc.) and perform tasks autonomously by using an active sensory-control system, or with guidance, typically by teleoperation, in which case, some of the functions of an active sensory-control system are taken over by operator.”

Ever since the end of the 19th century we have been engineering “things” composed of sensors, actuators, and control systems intertwined such that these “things” have a lifelike appearance and often useful practical applications. These “things” are synthetic organisms, also called robots.

Nikola Tesla, Serbian inventor who lived most of his life in the United States, is credited with the creation of the first robot at the end of the 19th century. He invented a remote control and patented a radio-controlled robot-boat (referred to as teleautomaton) on November 8, 1898. In September 1898, Tesla demonstrated his invention. He used radio waves to move a robot-boat in a small pool of water in Madison Square Garden in New York City during the Electrical Exhibition of 1898. According to his own words, inspiration for this invention was the human organism; instead of eyes, the boat used small antennas that would pick up radio ways. This sensory input was then processed by simple AND logical control gate (approximately half century before the invention of transistor) instead of by brain and appropriate propulsion would be accordingly created [13].

The word robot was eventually introduced in the play R.U.R. (Rossum's Universal Robots) by Czech author Karel Capek published in 1920. Karel Capek's robots were built in the human form. They were allowed to physically interact with humans and operate in the same workplaces as humans do. Karel Capek would probably be amused to learn that such robots are now also called cobots or co-robots (from collaborative robots).

Chapter 6 addresses neural interfaces, for example, high-resolution peripheral neuromuscular interfaces and cortical microelectrode technologies. These interfaces can be used among others for diagnosis and monitoring or they can be an integral part of the biomechatronics system. One of the critical challenges in the field of advanced prosthesis, braces, exoskeletons/exomusculatures, and even wheelchairs is communication of user intent, that is, biological control command followed by appropriate actuation of synthetic (or engineered) system resulting in corresponding movement of the entire system. Moreover, to close the feedback loop it is also often highly desirable to communicate synthetic sensory output back to human neural control system; problem which in practice proved even harder than communication of biological command. Finally, new directions of research also address neural prosthesis as well as assistive and augmentative brain add-ons, that is, technologies that could deal with various brain-related deficiencies and maybe also fundamentally influence ways how we interface with the digital world, store and process our memories, communicate with each other, how long do we live, and how we perceive ourselves, that is, our likely substantially evolved identities. Clearly, the development of these technologies is likely to create a strong influence on the entire human race. And hence one cannot but wonder about the ethical consequences. However, as usual when technology is concerned, it is often not the technology that is good or evil.

Chapter 7 is focused on synthetic organs, tissues, and support systems. Numerous systems that are already in wide use as well as those that are still being actively developed and researched are addressed in this chapter. Topics include pacemakers, implantable artificial hearts, heart valves, blood vessels/stents, hearing aids, middle ear and cochlear implants, brainstem implants, artificial cornea, intraocular lens, visual prosthesis including retinal, optic nerve, or cortical prosthesis, breast prosthesis, dental implants, artificial skin in the context of wound dressing and cultured skin, artificial dura mater, etc. The cardiopulmonary bypass (CPB), or heart-lung machine, artificial respirator, artificial pancreatic islet, and artificial dialyzer are addressed as examples of support systems. It appears that the accelerated advancement of Health Science and Technology are bringing us closer and closer to the day when the majority of human body parts from macro to micro, that is, cellular or molecular level, will be easily exchangeable with engineered systems made of synthetic or biological elements. To assist that process, concepts addressed in the following chapter might prove to be very critical.

Chapter 8 discusses biomechatronics and robotics at the molecular and cellular levels. Imagine, soon in the future, a new generation of microrobots, nanorobots, and even biohybrid robots that could effectively assist with diagnosis, health monitoring, therapy, surgery, gene therapy, cell manipulation, cancer detection and treatment, drug delivery, tissue engineering, detoxification, etc. They operate at tiny scales where, for example, adhesion, Van der Waals, and capillary forces dominate and where our intuitive understanding of physics at macroscale is not as applicable. Hence, one needs to consider that viscous fluid dynamics at low Reynolds numbers are also referred to as Stokes flows and contemplate on various ratios including advection to diffusion, momentum diffusivity to thermal diffusivity, viscous forces to surface tension, gravity to surface tension, the molecular mean free path to the characteristic system length scale, and so on. What is the propulsion mechanism of these robots? Where is their energy coming from? How are they controlled? What type of actions they might be able to perform? The interested reader may want to review this chapter in great detail to find answers to these and other important questions.

Advanced assistive prosthesis, braces, and exoskeletons/exomusculatures/exosuits are addressed in Chapters 9–11, respectively. The robots that intimately interact with the human body probably necessitate the least introduction as they represent the more traditional biomechatronics systems. In...