Introduction to Robotics Jurek Sasiadek Department of Mechanical and Aerospace Engineering Carleton University MECH 4503
Course Objectives 1. The main objective of this course is to introduce students to basics of robotics. 2. The other objective is to give student brief overview of history of robotics, transformations, kinematics, dynamics, sensors and control related to robots.
Methodology used to meet course objectives I General History Transformation
Methodology used to meet course objectives II Robotics Kinematics Dynamics
Methodology used to meet course objectives III Robotics Control Systems Sensors
Definition of Robotics • Definition 1 : “any device which replaces human labour” • Definition 2 : “ a programmable multifunction manipulator designated to move materials, arts, or specialized devices through variable programmed motions for the performance of variety of tasks” Jurek Sasiadek
Definition of Robotics • Definition 3: “a robot is a machine which can be programmed to do variety of tasks, in the same way that a computer is an electronic circuit which can be programmed to do variety of tasks” • Definition 4: “robotics is an intelligent connection of perception to action” Jurek Sasiadek
Robotics is the discipline which involves: • Design, manufacture, control, and programming of robots; • Use of robots to solve problems; • Study of control processes, sensors and algorithms used in humans, animals and machines; • Application of these controls and algorithms to the design of robots Jurek Sasiadek
Robotics Engineering • Robotics engineering is concerned with design, construction and application of robots Jurek Sasiadek
Robotics Science • The goal of RS in not develepment of machines but to understand the physical and information processes underlying perception and action. Once basic concepts are understood, they can be used in the design of robots. Jurek Sasiadek
History of Robotics • 1921 – Karel Capek, Czech playwwriter and novelist wrote a play “RUR” (Rossum’s Universal Robots) Jurek Sasiadek
Karel Capek : • "It is with horror, frankly, that he rejects all responsibility for the idea that metal contraptions could ever replace human beings, and that by means of wires they could awaken something like life, love, or rebellion. He would deem this dark prospect to be either an overestimation of machines, or a grave offence against life. " [The Author of Robots Defends Himself - Karl Capek, Lidove noviny, June 9, 1935, translation: Bean Comrada] Jurek Sasiadek
RUR • Word ROBOTICS comes from the Czech language where “robota” means work • In the play RUR the machines (robots) revolted, killed their human master and took over the World Jurek Sasiadek
History of Robotics • 1926 – The first movie involving robots. • “Metropolis” was released in Germany Jurek Sasiadek
History of Robotics • 1939 – ELECTRO, a walking robot and his dog SPARKO were displayed at the New York World’s Fair Jurek Sasiadek
Electro and Sparko Jurek Sasiadek
Electro and Sparko • A robot and his electric dog. Sparko was built by Westinghouse as Elektro's robotic pet, though from his much more basic construction, I have a feeling that he was a bit of a slap-together job. Jurek Sasiadek
Sparko Jurek Sasiadek
Electro Jurek Sasiadek
History of Robotics • 1948 – Goertz is credited with development of teleoperator • 1948 Norbert Wiener publishes a book on cybernetics Jurek Sasiadek
History of Robotics • 1950 – Issac Asimov publishes his book “I, ROBOT” that revolves around intelligent humanoid robots designd according to certain laws • Clarke, Roger, "Asimov's Laws for Robotics: Implications for Information Technology", Part 1 and Part 2, Computer, December 1993, pp. 53 -61 and Computer, January 1994, pp. 57 -65. Jurek Sasiadek
Asimov’s laws • • Law Zero: A robot may not injure humanity, or, through inaction, allow humanity to come to harm. Law One: A robot may not injure a human being, or, through inaction, allow a human being to come to harm, unless this would violate a higher order law. Law Two: A robot must obey orders given it by human beings, except where such orders would conflict with a higher order law. Law Three: A robot must protect its own existence as long as such protection does not conflict with a higher order law. Jurek Sasiadek
History of Robotics • 1968 – GE (General Electric) built a quadrupedal walking machines • 1968 – GM (General Motors) installed its first Unimation robot • 1969 – a mobile robot was designed and built at Stanford University Jurek Sasiadek
Robot History • Shakey (Stanford Research Institute) – the first mobile robot to be operated using AI techniques • Simple tasks to solve: – To recognize an object using vision – Find its way to the object – Perform some action on the object (for example, to push it over) http: //www. frc. ri. cmu. edu/~hpm/book 98/fig. ch 2/p 027. html Jurek Sasiadek
Shakey Jurek Sasiadek
The Stanford Cart Hans Moravec • 1973 -1979 http: //www. frc. ri. cmu. edu/users/hpm/ – Stanford Cart – Equipped with stereo vision. – Take pictures from several different angles – The computer gauged the distance between the cart and obstacles in its path Jurek Sasiadek
History of Robotics • 1970 – Lunokhod, a first unmanned rover designed in Russia explored the surface of the Moon • 1970’s and 80’s – exponential grow in the field of robotics Jurek Sasiadek
Contemporary robotics • Jurek Sasiadek
Types of Robots • Robot Manipulators • Mobile Manipulators Jurek Sasiadek
Types of Robots • Locomotion Aerial Robots Wheeled mobile robots Legged robots Humanoid Underwater robots Jurek Sasiadek
Mobile Robot Examples Hilare II http: //www. laas. fr/~matthieu/robots/ Sojourner Rover NASA and JPL, Mars exploration Jurek Sasiadek
Autonomous Robots Jurek Sasiadek
Autonomous robot helicopter • Goal: To develop a vision-guided robot helicopter which can autonomously carry out functions applicable to search and rescue, surveillance, law enforcement, inspection, mapping, and aerial cinematography, in any weather conditions and using only on-board intelligence and computing power http: //www-2. cs. cmu. edu/afs/cs/project/chopper/www/haughton-do. html Jurek Sasiadek
Installed Industrial Robots Jurek Sasiadek
How are they used? • Industrial robots – 70% welding and painting – 20% pick and place – 10% others • Research focus on – Manipulator control – End-effector design • Compliance device • Dexterity robot hand – Visual and force feedback – Flexible automation Jurek Sasiadek
Robot Arm Dexterity Jurek Sasiadek
Robotics: a much bigger industry • Robot Manipulators – Assembly, automation • Field robots – Military applications – Space exploration • Service robots – Cleaning robots – Medical robots • Entertainment robots Jurek Sasiadek
Field Robots Jurek Sasiadek
Field Robots Jurek Sasiadek
Service robots Jurek Sasiadek
Is this you future? Jurek Sasiadek
What is AI • • Knowledge representation Understanding natural language Learning Planning and problem solving Inference Search Vision Jurek Sasiadek
Learning and Evolution • Learning – Skills vs Task (Map acquisition) • Learning Methods – Learning by instruction – Learning by imitation – Learning by skill transfer • Evolution and adaptation Jurek Sasiadek
The early stage of AI Jurek Sasiadek
Autonomous and Intelligence Jurek Sasiadek
The Honda Humanoid (1997) Jurek Sasiadek
Humanoid Jurek Sasiadek
Robot Applications • Manufacture Industry – Assembling – Automation • Biotechnology – Micro/Nano manipulation – Sample Handling – Automated Analysis Jurek Sasiadek
Robot Applications • Military Applications Jurek Sasiadek
Military Applications • DARPA Programs: (Defense Advanced Research Projects Agency) Tactical Mobile Robotics Jurek Sasiadek
Robot Applications • Fire Fighting, Search and Rescue Jurek Sasiadek
Robot Applications • Robots for Assistive Technology Jurek Sasiadek
Robot Applications • Entertainment Industry Jurek Sasiadek
Robot Applications • Entertainment Robots Sony-Qrio Jurek Sasiadek
Classification of Robots • JIRA – Japanese Industrial Robot Association • RIA – Robotics Institute of America • AFRI – Association Francaise de Robotique Jurek Sasiadek
JIRA Classification • • • Class 1 – manual handling devices Class 2 – fixed sequence robots Class 3 – variable sequence robots Class 4 – playback robots Class 5 – numerical control robots Class 6 – intelligent robots Jurek Sasiadek
RIA Classification Classes 3, 4, 5, 6 from JIRA are considered to be robots Jurek Sasiadek
AFRI Classification • Type 1 = class 1 JIRA - manual control and telerobotics • Type B = classes 2 and 3 – automatic handling devices with predetermined cycle • Type C = Classes 4 and 5 – programmable robots • Type D = class 6 Jurek Sasiadek
Types of Robot Motion Control • Point to point – spot welding, pick and place operation, loading and unloading • Continuous path - spray painting, arc welding, gluing Jurek Sasiadek
Types of Robots Stationary/ Manipulators Mobile Jurek Sasiadek
Types of Robots Manipulators Arm Gantry Jurek Sasiadek SCARA (Selective Compliance Artificial Research Arm)
Gantry Type Robot Gantry kinematics Jurek Sasiadek
SCARA Jurek Sasiadek
SCARA specs Jurek Sasiadek
SCARA • Adept Technologies Robot Jurek Sasiadek
Types of Robots Mobile robots Flying and floating robots Surface on-road robots Jurek Sasiadek Surface off-road robots
Surface off-road • Walking Jurek Sasiadek
Mobile Robots Jurek Sasiadek
i. Robot- ATRV Jurek Sasiadek
Technical Specs • ATRV mobile robot Sonar 11 (6 forward facing, 4 side facing, 2 rear facing) CPU's. Pentium based ATX computer system. Communications. Optional wireless radio Ethernet. Batteries 4 lead acid, 1440 W-hr. Run Time 4 to 6 hours terrain dependent. Motor 4 high torque, 24 V DC servo motors. Drive 4 -wheel differential. Turn Radius. Zero (skid steer)Translate Speed 2 m/s 6. 6'/s. Rotate Speed 70°/s. Approach Angle 45°Decent Angle 45°Payload 100 kg 220 lbs. Height 65 cm 25. 6"Length 105 cm 41. 3"Width 80 cm 31. 5"Weight 118 kg 260 lbs Replacement Battery Pack Vision Systems Individual Vision Components Wireless Communications SICK® LMS Laser Scanner ASCII to Speech Interface Front and Rear Bumper Tactiles Computerized Navigation Compass 12 Channel GPS Receiver Inertial Sensors Jurek Sasiadek
Robot characteristics Rhino XR-3 • • Number of axis – 5 Load carrying capacity – 0. 5 kg Max speed, cycle time – 25 cm/s Reach and stroke – horizontal (62. 23 mm), vertical (88. 27 mm) • Tool orientation – pitch (270 deg), roll (∞) • Repeatability – 0. 5 mm • Precision and Accuracy - …… Jurek Sasiadek
Robot Specification • Repeatability - is a measure of the ability of the robot to position the tool tip in the same place repeatedly • Accuracy – is a measure of the ability of the robot to place the tool tip at an arbitrarily prescribed location in the work envelope Jurek Sasiadek
Robot specification (cont) • Precision – is a measure of a spatial resolution with which the tool can be positioned within the work envelope Jurek Sasiadek
Precision A B Accuracy Jurek Sasiadek
Manipulators • Robot Configuration: Cartesian: PPP Cylindrical: RPP Spherical: RRP Hand coordinate: SCARA: RRP Articulated: RRR n: normal vector; s: sliding vector; (Selective Compliance Assembly Robot Arm) a: approach vector, normal to the tool mounting plate
Robot Configurations • Cartesian – joints: prismatic waist x, prismatic shoulder y, prismatic z • Cylindrical – joints: revolute waist Θ, prismatic shoulder z, prismatic elbow r • Spherical (Polar) – joints: revolute waist Θ, revolute shoulder Φ, prismatic elbow r Jurek Sasiadek
Robot Configuration • Anthropomorphic – joints: revolute waist Θ, revolute shoulder Φ, revolute elbow Ψ • SCARA (Selective Compliance Artificial Research Arm) Jurek Sasiadek
Cartesian configuration • Advantages: linear motion in three directions; simple kinematics model; rigid structure; easy to visualize; can use inexpensive pneumatic drives for pick and place operations Jurek Sasiadek
Cartesian (cont) • Disadvantages: require a large volume to operate in; work space is smaller than robot volume; unable to reach areas under objects; guiding surfaces of prismatic joints must be covered to prevent ingress of dust Jurek Sasiadek
Cylindrical configuration • Advantages: simple kinematics model; easy to visualize, good accesses into cavities and machine openings; very powerful when hydraulic drives used • Disadvantages: restricted work envelope, prismatic guides difficult to seal from dust and liquids; back side of robot can overlap with work volume Jurek Sasiadek
Spherical configuration • Advantages: covers a large volume from a central support; can bend down to pick objects up off the floor • Disadvantages: complex kinematics model; difficult to visualize Jurek Sasiadek
Articulated configuration • Advantages: maximum flexibility; covers a large work space relative to the volume of robots; revolute joints are easy to seal; suits electric motors; can reach over and under objects Jurek Sasiadek
Articulated configuration (cont. ) • Disadvantages: complex kinematics, difficult to visualize, control of linear motion is difficult, structure not very rigid at full reach Jurek Sasiadek
Robot design • Potential weak points in mechanical design Jurek Sasiadek
Permanent deformation of total structure or single components Corrective measures : - increase stiffness; - reduce weight; - counterbalance Jurek Sasiadek
Dynamic deformation • - Corrective measures: Increase stiffness; Reduce the mass to be moved; Distribute mass Jurek Sasiadek
Backlash • Corrective measures: - Reduce backlash in gears; - Use stiffer transmission elements Jurek Sasiadek
Bearing clearance • Corrective measures: - Use prestressed bearings; Jurek Sasiadek
Friction • Corrective measures: -improve bearing clearance; -increase lubrication Jurek Sasiadek
Thermal effects • Corrective measures: - Isolate the heat source Jurek Sasiadek
Poor connection of transducers • Corrective measures; - Improve mechanical connection; - Find a better location; - Shield against environment Jurek Sasiadek
Robots main parts • Joints • Links • Actuators Jurek Sasiadek
Joints - Prismatic (linear) - Revolute - Spherical Jurek Sasiadek
Links • Robots links are powered by actuators Jurek Sasiadek
Robot Actuators • Pneumatic • Hydraulic • Electric Jurek Sasiadek
Pneumatic Actuators • Advantages: -relatively inexpensive; -high speed; -do not pollute workspace with fluids; -can be used in laboratory work; -actuator can stall without damage; -use common source of energy in industry Jurek Sasiadek
Pneumatic Actuators • Disadvantages: -compressibility of air limits their accuracy; -noise pollution; -leakage of air is a major concern; -additional air filtering and drying system is needed; -difficult with speed control Jurek Sasiadek
Hydraulic Actuators • Advantages: -large lift capacity; -fast response; -very good servo control; -offers accurate control; - oil is incompressible, hence once positioned joints can be held motionless; -self lubricating and self cooling Jurek Sasiadek
Hydraulic Actuators • Disadvantages: -hydraulic systems are expensive; -they pollute the workspace with fluids and noise; -not suitable for really high speed cycling Jurek Sasiadek
Electric Actuators • Advantages: -fast and accurate; -it is possible to apply sophisticated control techniques; -easily available and relatively inexpensive; -simple to use; -new rare Earth (Sm. CO 5 samarium cobalt) motors have high torques, reduced weight and fast response Jurek Sasiadek
Electric Actuators • Disadvantages: -require gear trains or the like for transmission of power; -gear backlash limits precision; -electric arcing might be a problem; -power limit; -problems with overheating in stalled conditions; -brake are needed to lock them in position Jurek Sasiadek
Electric motor selection consideration • Mechanical specification: -mechanical time constant; -no-load speed and acceleration; -rated torque; -rated output power; -frictional torques; -damping constant; -dimension and weight; -armature moment of inertia Jurek Sasiadek
Electric motor selection (cont) • Electrical specification: -electrical time constant; -input power; -armature resistance and inductance; -field resistance and inductance; -compatible drive circuit specification Jurek Sasiadek
Electric motor selection (cont. ) • General specification: -brush life and motor life; -efficiency; -operating temperature and other environment conditions; -heat transfer; -mounting configurations; -coupling methods Jurek Sasiadek
Actuators • Actuators are usually components of so called, “servo control mechanism” • Servo control of robots actuators acts on three main variables: -movement (angular or linear); -speed (angular or linear); -torque (or force) Jurek Sasiadek
Robots Servo systems • Positional • Speed • Torque Jurek Sasiadek
Sensors Internal External Jurek Sasiadek
Sensors Internal (Motion Sensors) Potentiometers Tachometers Microswitches Jurek Sasiadek Encoders
Internal Sensors • Encoders Jurek Sasiadek
Sensors External Contact Non-contact Jurek Sasiadek
Sensors Contact Pressure sensors Tactile sensors Jurek Sasiadek Force and Torque Sensors/ Inertial Sensors
Inertial Sensors Navigation systems Computerized Navigation Compass • • • One-axis heading sensor with 0. 5 degree accuracy RS-232 communication port Auto-calibration compensates for field effects of other on-board equipment Inertial Navigation Sensor 3 -axis pitch/roll/yaw gyros 3 -axis pitch/roll/yaw accelerometers 150 degrees per second gyro rate 10 Hz gyro bandwidth 100 Hz accelerometer bandwidth RS-232 communications interface Low power consumption Jurek Sasiadek
Inertial Systems Absolute Orientation Sensor • • • Heading accuracy of 1. 5 degrees Heading resolution of 0. 1 degrees Heading repeatability of 0. 3 degrees Tilt accuracy of 0. 4 degrees Tilt resolution of 0. 3 degrees Tilt repeatability of 0. 3 degrees Tilt range of 50 degrees RS-232 communications interface Low power consumption Mobility Robot Integration support Jurek Sasiadek
Sensors Non-contact Vision systems Radar and Sonar sensors Jurek Sasiadek Range sensors
Vision Systems • • • Vision Systems and Components High-Performance Stereo Vision System Fully assembled and configured. Available on the ATRV, ATRV-Jr and B 21 r robots. • • 2 PCI Frame Grabbers Pan-Tilt Head 2 XC 999 Color CCD cameras with 6 mm lenses (NTSC or PAL) Custom, adjustable stereo camera mounting bar Synchronization electronics Power, signal and control cabling Mobility Robot Integration support for individual components Jurek Sasiadek
Range Sensors • SICK Proximity Laser Scanner • • Pulsed IR 164' (50 m) range 180 -degrees coverage 0. 5% angle resolution +/- 50 mm dist. measurement resolution Mobility Robot Integration support • • • Pulsed IR 492'(150 m) range 180 -degrees coverage 0. 5% angle resolution +/- 50 mm dist. measurement resolution Mobility Robot Integration support SICK Laser Measurement System Jurek Sasiadek
Robot Actuators Pneumatic Hydraulic Jurek Sasiadek Electric
Electric Actuators • • • Stepper Synchronous AC servo Brushless DC servo Brushed DC servo Direct drive motors Jurek Sasiadek
Stepper motors Jurek Sasiadek
Controllers Jurek Sasiadek
Controllers • Boards Jurek Sasiadek
Robotics • • What is the future of robotics? UAV? Service robots? Humanoid robots? Jurek Sasiadek
Homogeneous Transformations • • Vectors: x, y, v Planes: P, A Coordinate frames: CONV, H Arrays: A, B, C, D Jurek Sasiadek
Homogeneous Transformation (cont. ) • To describe a point in space, which we call p, with respect to a coordinate frame E: Ev • The same point p with respect to a different coordinate frame, for example H is described : Hw Jurek Sasiadek
HT Example • The tip of a pin might be described as a vector tip, with respect to a frame BASE as BASE tip Jurek Sasiadek
HT Vectors • The homogenous coordinate representation of objects in n-space is an n+1 space entity such that a particular perspective projection recreates the n-space • It can also be viewed as an addition of an extra coordinate to each vector, such that the vector has the same meaning if each component, including the scale vector, is multiplied by a constant Jurek Sasiadek
HT Vectors (cont. ) • A point vector v = ai +bj + ck , where i, j, k are unit vectors along x, y, z coordinate axis, respectively, is represented in homogeneous coordinates as a column matrix, e. g. v= Jurek Sasiadek
HT Where a = x/w ; b = y/w ; c = z/w thus the vector 3 i+4 j+5 k can be represented as [3 4 5 1]T or as [6 8 10 2]T. Jurek Sasiadek
Trajectory Planning • A path is a set of points in operational or joint space that the end point of manipulator has to follow. A path is a geometric description of motion Jurek Sasiadek
Trajectory Planning • A trajectory is a path on which the time constraints have been specified, e. g. velocities and/or accelerations are specified at each points Jurek Sasiadek
Joint space trajectories • Joint space trajectory planning algorithm requirements: - to generate smooth trajectory, not too demanding from computational point of view - joint positions and velocities have to be continuous functions Jurek Sasiadek
Trajectory and motion planning • Point-to-point motion • Path motion Jurek Sasiadek
Point-to point motion • Optimization problem - For chosen angular joint velocity, determine the solution of the differential equation (1) subject to the condition (2) Jurek Sasiadek
Скачать презентацию Introduction to Robotics Jurek Sasiadek Department of Mechanical
ec1d939acb7f12ba5d5a26bfc94940fa.ppt