01Introduction to Robotics(Chapter3)
MIT Introduction to Robotics, Chapter 1 Introduction
- 2.12 Lecture Notes -H. Harry AsadaFord Professor of Mechanical EngineeringFall 2005Introduction to Robotics, H. Harry Asada 1Chapter 1IntroductionMany definitions have been suggested for what we call a robot. The word may conjure up various levels of technological sophistication, ranging from a simple material handling device to a humanoid. The image of robots varies widely with researchers, engineers, and robot manufacturers. However, it is widely accepted that today’s robots used in industries originated in the invention of a programmed material handling device by George C. Devol. In 1954, Devol filed a U.S. patent for a new machine for part transfer, and he claimed the basic concept of teach-in/playback to control the device. This scheme is now extensively used in most of today's industrial robots.1.1 Era of Industrial RobotsDevol's industrial robots have their origins in two preceding technologies: numerical control for machine tools, and remote manipulation. Numerical control is a scheme to generate control actions based on stored data. Stored data may include coordinate data of points to which the machine is to be moved, clock signals to start and stop operations, and logical statements for branching control sequences. The whole sequence of operations and its variations are prescribed and stored in a form of memory, so that different tasks can be performed without requiring major hardware changes. Modern manufacturing systems must produce a variety of products in small batches, rather than a large number of the same products for an extended period of time, and frequent changes of product models and production schedules require flexibility in the manufacturing system. The transfer line approach, which is most effective for mass production, is not appropriate when such flexibility is needed (Figure 1-1). When a major product change is required, a special-purpose production line becomes useless and often ends up being abandoned, despite the large capital investment it originally involved. Flexible automation has been a centralFigure 1-1 General trend of manufacturing cost vs. batch sizeIntroduction to Robotics, H. Harry Asada 2 issue in manufacturing innovation for a few decades, and numerical control has played a central role in increasing system flexibility. Contemporary industrial robots are programmable machines that can perform different operations by simply modifying stored data, a feature that has evolved from the application of numerical control.Another origin of today's industrial robots can be found in remote manipulators. A remote manipulator is a device that performs a task at a distance. It can be used in environments that human workers cannot easily or safely access, e.g. for handling radio-active materials, or in some deep sea and space applications. The first master-slave manipulator system was developed by 1948. The concept involves an electrically powered mechanical arm installed at the operation site, and a control joystick of geometry similar to that of the mechanical arm (Figure 1-2). The joystick has position transducers at individual joints that measure the motion of the human operator as he moves the tip of the joystick. Thus the operator's motion is transformed into electrical signals, which are transmitted to the mechanical arm and cause the same motion as the one that the human operator performed. The joystick that the operator handles is called the master manipulator, while the mechanical arm is called the slave manipulator, since its motion is ideally the replica of the operator's commanded motion. A master-slave manipulator has typically six degrees of freedom to allow the gripper to locate an object at an arbitrary position and orientation. Most joints are revolute, and the whole mechanical construction is similar to that of the human arm. This analogy with the human arm results from the need of replicating human motions. Further, this structure allows dexterous motions in a wide range of workspaces, which is desirable for operations in modern manufacturing systems.and remote manipulation. Thus a widely accepted definition of today’s industrial robot is that of a numerically controlled manipulator, where the human operator and the master manipulator in the figure are replaced by a numerical controller.Figure removed for copyright reasons.See Figure 1-4 in Asada and Slotine, 1986.Figure 1-3 White body assembly lines using spot welding robots1.2 Creation of RoboticsThe merge of numerical control and remote manipulation created a new field of engineering, and with it a number of scientific issues in design and control which are substantially different from those of the original technologies have emerged.Robots are required to have much higher mobility and dexterity than traditional machine tools. They must be able to work in a large reachable range, access crowded places, handle a variety of workpieces, and perform flexible tasks. The high mobility and dexterity requirements result in the unique mechanical structure of robots,which parallels the human arm structure. This structure, however, significantly departs from traditional machine design.A robot mechanical structure is basically composed of cantilevered beams, forming a sequence of arm links connected by hinged joints. Such a structure has inherently poor mechanical stiffness and accuracy, hence is not appropriate for the heavy-duty, high-precision applications required of machine tools. Further, it also implies a serial sequence of servoed joints, whose errors accumulate along the linkage. In order to exploit the high mobility and dexterity uniquely featured by the serial linkage, these difficulties must be overcome by advanced design and control techniques.The serial linkage geometry of manipulator arms is described by complex nonlinear equations. Effective analytical tools are necessary to understand the geometric and kinematic behavior of the manipulator, globally referred to as the manipulator kinematics. This represents an important and unique area of robotics research, since research in kinematics and design has traditionally focused upon single-input mechanisms with single actuators moving at constant speeds, while robots are multi-input spatial mechanisms which require more sophisticated analytical tools.The dynamic behavior of robot manipulators is also complex, since the dynamics of multi-input spatial linkages are highly coupled and nonlinear. The motion of each joint is significantly affected by the motions of all the other joints. The inertial load imposed at each joint varies widely depending on the configuration of the manipulator arm. Coriolis and centrifugal effects are prominent when the manipulator arm moves at high speeds. The kinematic and dynamic complexities create unique control problems that are not adequately handled by standard linear control techniques, and thus make effective control system design a critical issue in robotics.Figure removed for copyright reasons.See Figure 1-4 Adept Direct-Drive robotFinally, robots are required to interact much more heavily with peripheral devices than traditional numerically-controlled machine tools. Machine tools are essentially self-contained systems that handle workpieces in well-defined locations. By contrast, the environment in which robots are used is often poorly structured, and effective means must be developed to identify the locations of the workpieces as well as to communicate to peripheral devices and other machines in a coordinated fashion. Robots are also critically different from master-slave manipulators, in that they are autonomous systems. Master-slave manipulators are essentially manually controlledFigure 1-5 Dexterous fingersPhoto removed for copyright reasons.See /viewdetails/item/313/size/300/3/'Also published Menzel, Peter, and Faith D’Aluisio. Robo Sapiens: Evolution of a New Species . Cambridge, MA: MIT Press, 2001, p. 176.'Figure 1-6 Medical robots for minimally invasive surgerysystems, where the human operator takes the decisions and applies control actions. The operator interprets a given task, finds an appropriate strategy to accomplish the task, and plans theprocedure of operations. He/she devises an effective way of achieving the goal on the basis of his/her experience and knowledge about the task. His/her decisions are then transferred to the slave manipulator through the joystick. The resultant motion of the slave manipulator ismonitored by the operator, and necessary adjustments or modifications of control actions are provided when the resultant motion is not adequate, or when unexpected events occur during the operation. The human operator is, therefore, an essential part of the control loop. When the operator is eliminated from the control system, all the planning and control commands must be generated by the machine itself. The detailed procedure of operations must be set up in advance, Photo removed for copyright reasons.Robot hand holding lightbulb - http://www.dlr.de/rm/en/Desktopdefault.aspx/tabid-426/569_read-76/_____________________________________________________________and each step of motion command must be generated and coded in an appropriate form so that the robot can interpret it and execute it accurately. Effective means to store the commands and manage the data file are also needed . Thus, programming and command generation are critical issues in robotics. In addition, the robot must be able to fully monitor its own motion. In order to adapt to disturbances and unpredictable changes in the work environment, the robot needs a variety of sensors, so as to obtain information both about the environment (using external sensors, such as cameras or touch sensors) and about itself (using internal sensors, such as joint encoders or joint torque sensors). Effective sensor-based strategies that incorporate this information require advanced control algorithms. But they also imply a detailed understanding of the task.1.3. Manipulation and Dexterityof robots to ever more advanced tasks. Robots arehuman assistance or intervention. To extend theapplications and abilities of robots, it becomesimportant to develop a sound understanding of thetasks themselves.develop effective control algorithms, we need toprecisely understand how a given task should beaccomplished and what sort of motions the robotoperation, for example, we need to know how toit withway. In a grinding operation, the robot mustposition the grinding wheel whileaccommodating the contact force. We need toanalyze the grinding process itself in order togenerate appropriate force and motioncommands.A detailed understanding of the underlying principles and "know-how" involved in the task must be developed in order to use industrial robots effectively, while there is no such need for making control strategies explicit when the assembly and grinding operations are performed by a human worker. Human beings perform sophisticated manipulation tasks without being aware of the control principles involved. We have trained ourselves to be capable of skilled jobs, but in general we do not know what the acquired skills are exactly about. A sound and explicit understanding of manipulation operations, however, is essential for the long-term progress of robotics. This scientific aspect of manipulation has never been studied systematically before, and represents an emerging and important part of robotics research.1.4 Locomotion and NavigationRobotics has found a number of important application areas in broad fields beyond manufacturing automation. These range from space and under-water exploration, hazardous waste disposal, and environment monitoring to robotic surgery, rehabilitation, home robotics, and entertainment. Many of these applications entail some locomotive functionality so that the robot can freely move around in an unstructured environment. Most industrial robots sit on a manufacturing floor and perform tasks in a structured environment. In contrast, those robots for non-manufacturing applications must be able to move around on their own. See Figure 1-8. Locomotion and navigation are increasingly important, as robots find challenging applications in the field. This opened up new research and development areas in robotics. Novel mechanisms are needed to allow robots to move through crowded areas, rough terrain, narrow channels, and even staircases. Various types of legged robots have been studied, since, unlike standard wheels, legs can negotiate with uneven floors and rough terrain. Among others, biped robots have been studied most extensively, resulting in the development of humanoids, as shown in Figure 1-9. Combining leg mechanisms with wheels has accomplished superior performance in both flexibility and efficiency. The Mars Rover prototype shown below has a rocker-buggy mechanism combined with advanced wheel drives in order to adapt itself to diverse terrain conditions. See Figure 1-10.Photo removed for copyright reasons.Figure 1-8 Automatically guided vehicle for meal delivery in hospitalsPhoto removed for copyright reasons.Figure 1-9 Honda’s P3 humanoid robotNavigation is another critical functionality needed for mobile robots, in particular, for unstructured environment. Those robots are equipped with range sensors and vision system, and are capable of interpreting the data to locate themselves. Often the robot has a map of the environment, and uses it for estimating the location. Furthermore, based on the real-time data obtained in the field, the robot is capable of updating and augmenting the map, which is incomplete and uncertain in unstructured environment. As depicted in Figure 1-10, location estimation and map building are simultaneously executed in the advanced navigation system. Such Simultaneous Location and MApping (SLAM) is exactly what we human do in our daily life, and is an important functionality of intelligent robots.The goal of robotics is thus two-fold: to extend our understanding about manipulation, locomotion,and other robotic behaviors and to develop engineering methodologies to actually perform desired tasks. The goal of this book is to provide entry-level readers and experienced engineers with fundamentals of understanding robotic tasks and intelligent behaviors as well as with enabling technologies needed for building and controlling robotic systems.Figure 1-10 JPL’s planetary exploration robot: an early version of the Mars Rover。
机器人控制技术 (4)
Introduction to Robotics:ControlProfessor Qihong ChenSchool of Automation, Wuhan Univ. ofTechnologyE‐mail: qh_chen@TextbookReferenceChapter 1 Introduction1.1 BackgroundIndustrial robot became identifiable as a unique device in the 1960s. The latest trends inthe automation of the manufacturing process:•Industrial Robot(computer•CAD ‐aided design)•CAM (computer‐aided manufacturing)ofunit sNumber•Undersea robot (Germany)This course focuses on the control of the pmost important form of the industrial robot, mechanical manipulator121.2 The control of mechanical Manipulator 1.2.1 Description of position and orientationIn robotics, we constantlythe study of are concerned with the location of objects in three‐dimensionalspaceCoordinate system (Frame)•Any frame can serve as a reference system within which position and orientation to express the of a bodydescription of these attributes •Transforming the from one frame to another1221.2.2 Forward Kinematics •Kinematics is the science of motion that treatsi i i h i f i h motion without regard to the forces which cause it.•Within the science of kinematics, one studies,position, velocity, acceleration, and all higherporder derivatives of the position variables •The study of the kinematics of manipulators refers to all the geometrical and time‐based properties of the motion•Degrees of freedom (DOF)Thenumber of independent position variables.In the case of typical industrial robot, theq j number of DOF equals the number of joints:(1) A manipulator is usually an open chain(2) each joint position is defined with a single variable•Forward kinematics is a static geometrical p p g pproblem of computing the position and orientation of the end‐effector of the manipulator1231.2.3 Inverse kinematicsGiven the position and orientation of thepend‐effector of the manipulator, calculate all possible sets of joint angles that could be used to attain this given orientation.position and orientation•Singularity of mechanismThat does not prevent arobot arm from positioning anywhere within its workspace,the but can cause problems with motions of arm in their neighborhood.1.2.4 Dynamics124Dynamics is a huge field of study devoted to y g qstudying the forces required to cause motion.One method of controlling a manipulator to O h d f lli i l follow a desired path involves calculating actuator torque functions by using the dynamic equations of motion of the manipulator.1.2.5 Trajectory generation125A common way of moving a manipulator from here to there in a smooth,controlled fashion is to cause each joint to move as specified by a smooth function of time.timeExactly how to compute these motion functions is the problem trajectoryof generation.126position1.2.6 Linear controlActuators: stepper motors, servo motorsA primary concern of a position control is to compensate automatically for:()g p(1) Errors in knowledge of the parameters(2) Suppress disturbancepIn order to cause the manipulator to follow the desired trajectory, a position control system be implemented.must implemented1271.2.7 Force controlControl forces of contact when it touches pparts, tools, etcp y pComplementary to position control1.2.8 Programming robots 128•Robot programming language‐interface •Flexible‐different fromfixed automation。
Ch1.Introduction to Robotics
仿生技术有助于解决老龄化社会的家庭服务和医疗等问题，同时 也可有效缓解全球共同面临的器官源稀缺问题，给病患带来福音。
中南大学智能科学与技术系
Department of Intelligence Science and Technology, IST
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Top 10 Robot News in 2013
中南大学智能科学与技术系
Department of Intelligence Science and Technology, IST
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4 折衬衫机器人
自己动手的乐高折 叠衣服。你只需把它放 在一个平板盒子上，然 后按下开关。机器人会 翻转盒子的两翼，然后 非常完美地叠好衬衣。
中南大学智能科学与技术系
Department of Intelligence Science and Technology, IST
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2013年世界十大超酷机器人排行榜
1 终结者服装模特
名为《为我试衣》 或《终结者服装模特》 的机器人可以为你试衣 服，展现2000种不同的 体型，顾客可以看到机 器人试不同衣服的整个 过程。
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Robots in Imagination
中南大学智能科学与技术系
Department of Intelligence Science and Technology, IST
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Robots in Imagination
中南大学智能科学与技术系
Department of Intelligence Science and Technology, IST
机器人学导论
Introduction to Robotics
introduction to robotics
University of Pennsylvania
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University of Pennsylvania
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MEAM 520
What is a robot?
u Webster
An automatic apparatus or device that performs functions ordinarily ascribed to humans or operates with what appears to be almost human intelligence.
MEAM 520
History
u Origin of the word “robot”
l Czech word “robotnik” l 1920 play by Karel Capek l 1940s - Isaac Asimov’s science fiction
u History of automation
Leg 6 Leg 2 Leg 1
University of Pennsylvania
SParallel robot manipulators (continued)
Planar parallel manipulators
l capable of movements in the horizontal plane
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MEAM 520
The Honda Humanoid
University of Pennsylvania
MEAM 520
What is a robot?
Definition of a robot revisited
一机器人技术绪论精品PPT课件
1. 1 机器人学的发展 1．2 机器人的特点、结构与分类 1．3 机器人学与人工智能
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“机器人三原则”，阿西莫夫，科幻作家
1 机器人不应伤害人类； 2 机器人应遵守人类的命令，与第一条违背的命令 除外； 3 机器人应能保护自己，与第一条相抵触者除外。
• 适应性adaptivity---主要指其对工作环境变化的 适应能力 需具有（1）传感与测量环境变化的能力 （2）分析任务和执行操作规划的能力 （3）自动执行指令能力
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1.2机器人的特点、结构与分类
1.2.2机器人系统的结构 机器人系统由机械部分、环境测量、任务规
划、控制器等四部分组成，结构如图1.1。
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1.2机器人的特点、结构与分类
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1.2机器人的特点、 结构与分类
1.2.3机器人的自由度
1）刚体的自由度 任何空间刚体具有6个
自由度，即可任意运动。
2）机器人的自由度 机器人靠末端执行器工
作，末端执行器具有6个 自由度即可保证其灵活运 动。
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一般来讲，由之前我们所讲的刚体的自由度 来看，6自由度的机械臂已经足够确定末端物 体的位姿，那为什么有些机器人自由度大于6 呢？是不是多余呢？
• 1999年，日本索尼公司推出犬型机器人爱宝(AIBO)，当即销 售一空，从此娱乐机器人成为目前机器人迈进普通家庭的途 径之一
• 2006年 6月，微软公司推出Microsoft Robotics Studio，机器 人模块化、平台统一化的趋势越来越明显，比尔·盖茨预言 ，家用机器人很快将席卷全球
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第一代 第二代 第三代
第一个可编程机 器人，1954
Introduction to Robotics
History of Robotics (cont.)
• Two famous robots:
– Puma. (Programmable Universal Machine for Assembly). ‘78. – SCARA. (Selective Compliant Articulated Robot Assembly). ‘79.
Best soccer player ever
Best robot player ever
A Brief History of Robotics II
• Definition: a robot is a software-controllable mechanical device that uses sensors to guide one or more endeffectors through programmed motions in a workspace in order to manipulate physical objects. • Today’s robots are not androids built to impersonate humans. • Manipulators are anthropomorphic in the sense that they are patterned after the human arm. • Industrial robots: robotic arms or manipulators
机器人学基础 第1章 绪论 蔡自兴0
Robots
Robotics and AI
Ch. 1 Introduction
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Ch. 1 Introduction
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1 The U.S. "Big Dog"
In March 2008, the U.S. government released a video of the military robots called "Big Dog", which has amazing mobility and adaptability. Latest "Big Dog" can climb up 35 ° slopes, carry more than 40 kg equipment, representing about 30% of its weight It can move along a simple route, or by remote control.
Ch. 1 Introduction
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7 Robot World Cup held in China for the first time
China successfully held the Robot World Cup through July 14-20, 2008 for the first time.
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机器人学的数学基础
数学基础/机器人运动学 机器人运动学
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讲授
讲授 讲授
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机器人动力学
机器人控制（1） 机器人控制（2）
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Introduction to Robotics_ch03
l
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Differential Motions of a Frame versus a Robot
A robot may be the cause of the differential motions of a frame, attached to the end effector.
1 z 0 0
z 1 0 0
Rot
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z,
z)
0
0 1 0
0 0 0 1
1 0 0 0 0 1 n 0 Rot(n, n) 0 n 1 0 0 0 0 1
1 0 o 0 0 1 0 0 Rot(o, o) o 0 1 0 0 0 0 1
1 a 0 0
a 1 0 0
Rot(a,
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Differential Motions of a Frame
Differential motions of a frame can be divided into the following:
Differential translations Differential rotations Differential transformations (combinations of
Resulting motion B
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mRoetisounlting
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Resulting motion
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What is the Jacobian
For an equation in the form of
yi fi (x1, x2 , x3,..., x j )
The derivatives are:
Introduction_to_Robotics 20
Robot Classes
Manipulators: robotic arms. These are
most commonly found in industrial settings. Mobile Robots: unmanned vehicles capable of locomotion. Hybrid Robots: mobile robots with manipulators.
(Images from AAAI and HowStuffWorks, respectively)
Robot Components
Body Effectors Actuators Sensors Controller Software
Robot::Body
Typically defined as a graph of links and joints:
6-DOFs Robot Arm
How many DOFs can you identify in your arm?
Robot::Effectors
Component to accomplish some desired physical function Examples:
Hands Torch Wheels Legs Trumpet?
Roomba Effectors
What are the effectors of the Roomba?
Roomba Effectors
What are the effectors of the Roomba?
Vacuum, brushes, wheels
Robotics
Robotics Introduction to RoboticsArtificial intelligence is the branch of computer science that deals with writing computer programs that can solve problems creatively; "workers in AI hope to imitate or duplicate intelligence in computers and robots"manipulator designed to move material, parts, tools, or specialized devices through various programmed motions for the performance of a variety of tasks" .•Or a simpler version•An automatic device that performs functions normally ascribed to humans or a machine in the form of a human.robotnik,meaning •First used to describe fabricated workers in a fictional 1920s play called Rossum’s Universal Robots by Czech author Karel Capek.The golems of medieval Jewish legend were robot-like servants made of clay, brought to life by a spoken•In 1495, Leonardo da Vinci drew plans for a mechanical man.•Real robots were only possible in the 1950s and 1960s with the introduction of transistors and integrated circuits., was created.was installed at a General Motors plant to work with heated die-casting machines .and science fiction stories , robots then started to appear on television shows, like Lost in Space and then in Hollywood movies.In Lost in Space the robot demonstrated human characteristics such as feelings and emotions.•Scientists today are still a long way off from programming robots which can think and act like humans.Robots in Fiction/Hollywood •Robby the Robot(1956)–the firstrobot seen at themovies• A scene fromForbidden Planet•Lost In Space (1965)•Star Warsthrough inaction, allow a human being to come A robot must obey orders given it by human beings, except where such orders would conflict with the First Law.•A robot must protect its own existence as long as such protection does not conflict with the First or Second Law.Types of Robots–improving productivity–LaboratoryapplicationsIn 1979 a nuclear accident in the USA caused a leak of radioactive material. Led to production of special robot–teleoperator to handle the radioactive material. Examples are Robolaband modern toys which are programmed to do things like talking, walking and dancing.perform a variety of tasks by moving parts, tools oradaptive robots -no way of sensing the environment, so do the job regardless of any environmental factors-get feedback from a sensor to alter the operation of the device.•Robots can also be classified according to whether they are stationary or mobile. Mobile robots are free to move around, but stationary robots remain in 1 place but have arms that move.Robots never get sick or¾Robots can do tasksconsidered too dangerous for humans.Robots can operateequipment to much higherprecision than humans.¾May be cheaper over the long term¾May be able to perform tasks that are impossible forhumansDangerous tasks •Impossible tasks•Robots assisting the handicapped.Exploring VolcanoesUnderwater Exploration •MEDICAL SCIENCE –Surgical assistant •ASSEMBLY-factoriesThe hardest thing any robot has to do is to be able to taught how to walk.dispose of bombs. About three feet long, the Mini-Andros looks something like a small armoured tank with eight wheels on four "legs" that extend for climbing stairs.flexible enough to do justabout anything a human cando.•Here is an example of some new development on creating robots that walk.。