(c) KSIS Politechnika Poznanska

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1 Fundamentals of Autonomous Systems Lecture 1 Dariusz Pazderski 1 1 Katedra Sterowania i In»ynierii Systemów, Politechnika Pozna«ska 7th March 2017

2 Rules and regulations Lecturer: Dariusz Pazderski room 419 EL oce hours Thursday, Lecture Assessment: Final exam: multi-choice test/open questions. The nal grade is a combination of the exam grade (2/3) and the laboratory exercise grade (1/3). Main topics: Fundamental denitions and concepts Review of control architectures Modelling of wheeled vehicles Motion control of nonholonomic vehicles Fundamental localization and navigation methods Numerical models of the environment Path and motion planning References: R. Siegwart, I. Nourbakhsh, to Autonomous Mobile Robots, MIT, R. C. Arkin (edytor), Principles of Robot Motion Theory, Algorithms and Implementation, Massachussets Institute of Technology (MIT), B. Siciliano, L. Sciavicco, L. Villani, G. Oriolo, Robotics: Modelling, Planning and Control, Springer B. Siciliano, O. Khatib (Ed.), Handbook of Robotics, Springer J. Borenstein (edytor), Where am I - Systems and Methods for Mobile Robot Positioning, Tcho«, Mazur, Hossa, Dul ba, Manipulatory i roboty mobilne, Akademia Ocyna Wydawnicza PLJ, P. Skrzypczy«ski, Metody analizy i redukcji niepewnosci percepcji w systemie nawigacji robota mobilnego, Rozprawy, nr 407, Wydawnictwo Politechniki Pozna«skiej, Poznan 2007.

3 Basic concepts Table of contents 1 Rules and regulations 2 Basic concepts Mobile robots Locomotion systems Selected applications of mobile robots Examples of (semi) autonomous mobile robots Ground vehicles Marine vehicles Flying vehicles Space vehicles

4 Basic concepts What is autonomy? (1) Figure: Dynamic system in the environment Denition (Basic denition of autonomy) Autonomy refers to systems capable of operating in the real-world environment without any form of external control for extended periods of time.

5 Basic concepts What is autonomy? (2) Mathematical general description Dene: Isolated dynamic environment (without external disturbances): Σ e : ẋ e = f e (x e,u e ), where x e denotes the state and u e is an input (initially u e = 0) Control system: Σ c : ẋ c = f c (x c,u c ) where x c state and u c input Next, consider interaction between the control system and the environment the environments acts on the control system: u c = f (x c,x e ) the control systems acts on the environment: u e = f (x c,x e ) nally we have mathematical autonomous system given by: ) Σ e : ẋ e = f e (x e, f (x c,x e ) ( Σ c : ẋ c = f c xc, f (x c,x e ) )

6 Basic concepts What is autonomy? (3) Living systems The unique examples of fully autonomous systems are living (biological) systems they can survive in a dynamic environment for extended periods maintain their internal structures and processes use the environment to locate and obtain materials for sustenance exhibit a variety of behaviours (such as feeding, foraging, and mating) they are capable of (partially) adapting to environment change Remark: Constant elements of the environment should not be considered as the autonomous systems. It is assumed that the autonomous systems are capable of operating in the word (they perform some function or task)!

7 Basic concepts What is autonomy? (4) Fundamental denition in mobile robotics Denition Mobile robot is a programmed machine which has ability to move in an environment, and one of its execution systems is the locomotion system. Mobile robots have a mobile platform and a manipulation part, which does not occur in the simplest versions (in such a case a mobile robot is considered equivalent to a mobile platform). Denition Autonomous mobile robot performs its tasks without the external help on part of a human. The basic property of such a system is its ability to develop and implement plans of action autonomously on the basis of the observation of its environment.

8 Basic concepts What is autonomy? (5) Basic tasks for a fully autonomous robot A fully autonomous robot has the ability to gain information about the environment (Rule #1) work for an extended period without human intervention (Rule #2) move either all or part of itself throughout its operating environment without human assistance (Rule #3) avoid situations that are harmful to people, property, or itself unless those are part of its design specications (Rule #4)

9 Basic concepts What is autonomy? (6) Limitations in practice Within the scope of the given autonomy denition the articial systems (robots) created by human are not fully autonomous! Building a fully autonomous robot essentially means devising a system equipped with advanced machine intelligence and capable of learning. An autonomous robot should be similar to a biological organism. However considering the current state of the art the possibility of imitating the living organisms is very limited. As a result the desired degree of autonomy is now unreachable! In practice the term autonomy can be considered as a theoretical concept, general idea or even a measure in order to estimate what level of autonomy is achieved by the particular system.

10 Mobile robots Table of contents 1 Rules and regulations 2 Basic concepts Mobile robots Locomotion systems Selected applications of mobile robots Examples of (semi) autonomous mobile robots Ground vehicles Marine vehicles Flying vehicles Space vehicles

11 Mobile robots Key denitions Perception the organization, identication and interpretation of sensory information in order to represent and understand the environment Localization the determination of a mobile robot's position (or/and orientation) in a selected coordinate frame Cognition a group of mental processes that includes attention, memory, producing and understanding language, learning, reasoning, problem solving, and decision making Navigation answers the question how a mobile robot is supposed to move in order to realise the desired task. Navigation problem = perception + localization + cognition

12 Mobile robots Abstract control scheme of (semi) autonomous robot Figure: Interaction robot-environment

13 Mobile robots Selected aspects of autonomy in robotics Figure: Fundamental elements of autonomy

14 Mobile robots Motion autonomy levels in robotics teleoperated system it is remotely controlled by an operator semi-autonomous system it is controlled by an operator, however it has ability to realize the prescribed task automatically (collision avoidance, reaching the selected point in an environment, passage through the door, etc.) autonomous system still unreachable!

15 Mobile robots Mobile robots classication Considering the type of environment the following classes of mobile robots can be distinguished: ground machines wheeled vehicles tracked vehicles walking machines (one legged hopping machine, two legged biped, four legged quadruped, six legged, etc.) water vehicles moving on the surface (ships, vessels) underwater aerial vehicles space vehicles

16 Locomotion systems Table of contents 1 Rules and regulations 2 Basic concepts Mobile robots Locomotion systems Selected applications of mobile robots Examples of (semi) autonomous mobile robots Ground vehicles Marine vehicles Flying vehicles Space vehicles

17 Locomotion systems Locomotion systems A mobile robot needs locomotion mechanisms which enable it to move unbounded throughout its environment. Locomotion is the complement of manipulation and it is related to interaction between the robot and the environment. Main issues: stability number and geometry of contact points center of gravity static/dynamic stability inclination of terrain charakteristic of contact contact point/path size and shape angle of contact friction type of environment structure medium (e.g. water, air, type of ground, etc.)

18 Locomotion systems Selected locomotion systems (1) Figure: Locomotion mechanisms used in biological systems (source R. Siegwart, I.R. Nourbakhsh, D. Scaramuzza, to Autonomous Mobile Robots, The MIT Press, 2011).

19 Locomotion systems Selected locomotion systems (2) Figure: A biped walking as an approximation of rolling locomotion (source R. Siegwart, I.R. Nourbakhsh, D. Scaramuzza, to Autonomous Mobile Robots, The MIT Press, 2011).

20 Locomotion systems Selected locomotion systems (3) Figure: Specic power verus attainable speed of various locomotion mechanisms (source R. Siegwart, I.R. Nourbakhsh, D. Scaramuzza, to Autonomous Mobile Robots, The MIT Press, 2011).

21 Selected applications of mobile robots Table of contents 1 Rules and regulations 2 Basic concepts Mobile robots Locomotion systems Selected applications of mobile robots Examples of (semi) autonomous mobile robots Ground vehicles Marine vehicles Flying vehicles Space vehicles

22 Selected applications of mobile robots Source: R. Siegwart, I.R. Nourbakhsh, D. Scaramuzza, to Autonomous Mobile Robots, The MIT Press, 2011

23 Examples of (semi) autonomous mobile robots Table of contents 1 Rules and regulations 2 Basic concepts Mobile robots Locomotion systems Selected applications of mobile robots Examples of (semi) autonomous mobile robots Ground vehicles Marine vehicles Flying vehicles Space vehicles

24 Examples of (semi) autonomous mobile robots Mobile systems in the industry: Automated Guided Vehicle (AGV) Figure: AGV transport system ( localised with optical or inductive line

25 Examples of (semi) autonomous mobile robots Transport systems in public environments Figure: TUG robot for transportation tasks in hospitals (

26 Examples of (semi) autonomous mobile robots Cleaning robots c e t li (c) IS S K Figure: P a ik n h a k s n na z o Po Robotics hoovers produced by irobot (

27 Examples of (semi) autonomous mobile robots Inspection robots Figure: Teleoperated robots: Robovolc automatic robotic system to explore and perform measurements in a volcanic environment ( and Inspector machine used by Polish police (

28 Examples of (semi) autonomous mobile robots Laboratory robots Figure: MTracker two-wheeled laboratory robot with DSP controller and mini PC board

29 Examples of (semi) autonomous mobile robots Unmmaned Surface Vessel (USV), Figure: USV CatOne multi purpose catamaran robots especially eective in shallow water, in situations that require recurring, very repetitive, long endurance activities or in those to be carried out in dangerous and hazardous environment and in sensitive ecosystems.

30 Examples of (semi) autonomous mobile robots Underwater robot Remotely Operated Underwater Vehicle (ROV) Figure: ROV Tiburon ( it was used for used for deep-sea research and provides autonomous hovering capabilities for the human operator..

31 Flying vehicles Table of contents 1 Rules and regulations 2 Basic concepts Mobile robots Locomotion systems Selected applications of mobile robots Examples of (semi) autonomous mobile robots Ground vehicles Marine vehicles Flying vehicles Space vehicles

32 Flying vehicles Classication of aerial systems Nonmotorized Balloon Lighter Than Air aerostat Motorized Blimp Aircraft Nonmotorized Glider Heavier Than Air aerodyne Plane Rotorcraft Birdlike Autogiro Motorized VTOL Figure: Specic power verus attainable speed of various locomotion mechanisms (source R. Siegwart, I.R. Nourbakhsh, D. Scaramuzza, to Autonomous Mobile Robots, The MIT Press, 2011).

33 Flying vehicles Selected ying machines A) B) C) D) Figure: Blimp (A), Glider (B), autogiro (C), VTOL aircraft (D)

34 Flying vehicles Flying principle comparison Airplane Helicopter Bird Autogiro Blimp Power cost Control cost Payload/volume Maneuverability Stationary ight Low speed y Vulnerability VTOL Endurance Miniaturization Indoor usage Total Source R. Siegwart, I.R. Nourbakhsh, D. Scaramuzza, to Autonomous Mobile Robots, The MIT Press, 2011

35 Flying vehicles Micro Aerial Vehicles (1) Figure: Examples of MAVs (source R. Siegwart, I.R. Nourbakhsh, D. Scaramuzza, to Autonomous Mobile Robots, The MIT Press, 2011)