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    UbiCom Book Slides 1 Ubiquitous computing: smart devices ... UbiCom Book Slides 1 Ubiquitous computing: smart devices ... Presentation Transcript

    • UbiCom Book Slides Chapter 6 Tagging, Sensing & Controlling Ubiquitous computing: smart devices, environments and interaction Stefan Poslad http://www.eecs.qmul.ac.uk/people/stefan/ubicom
    • Overview
      • Introduction 
      • Tagging the Physical World
      • Sensors and Sensor Networks
      • Micro Sensing & MEMS
      • Micro Actuation & MEMS
      • Embedded Systems and Real-time Systems
      • Control Systems (For Physical World Tasks)
      • Robots
      Ubiquitous computing: smart devices, environments and interaction
    • Chapter 6: Overview
      • The slides for this chapter are also expanded and split into several parts in the full pack
      • Part A: Tagging physical world & augmented reality
      • Part B: Sensors, Sensor Nets
      • Part C: MEMS
      • Part D: Embedded Systems
      • Part E: Control Systems & Robots
      Ubiquitous computing: smart devices, environments and interaction
    • Overview
      • Chapter 6 focuses on:
      • internal system properties: context-awareness & autonomy
      • external interaction with the physical environment.
      Ubiquitous computing: smart devices, environments and interaction
    • Introduction
      • To enable Smart (Physical) Environments, devices should:
      • Spread more into the physical environment, becoming part of more user activities in physical environment
      • Be cheap to operate: autonomous energy etc
      • Be low maintenance: automatic
      • Be able to interact with physical environment context
      • Be sometimes small enough so as to …
      • Be able to be encapsulated and embedded
      • Be cheap to manufacture
      Ubiquitous computing: smart devices, environments and interaction
    • UbiCom Internal System Properties Ubiquitous computing: smart devices, environments and interaction
    • Smart Physical Environments Ubiquitous computing: smart devices, environments and interaction
    • Ubiquitous computing: smart devices, environments and interaction
    • Overview
      • Introduction
      • Tagging the Physical World 
      • Sensors and Sensor Networks
      • Micro Actuation and Sensing: MEMS
      • Embedded Systems and Real-time Systems
      • Control Systems (For Physical World Tasks)
      • Robots
      Ubiquitous computing: smart devices, environments and interaction
    • Tagging (or Annotating) the Physical World
      • Outline of this section
      • Applications
      • Life-cycle for Tagging Physical Objects
      • Tags: Types and Characteristics
      • Physical and Virtual Tag Management
      • RFID Tags
      • Personalised and Social Tags
      Ubiquitous computing: smart devices, environments and interaction
    • Tagging: Applications
      • Locate items, e.g.?
      • Retrieve annotations associated with physical objects (augmented reality) e.g. ?
      • Security, e/g/. .
      • Tracking, e.g.,
      • Automated Routing: of physical objects, e.g., ?
      • Automated Physical Access: e.g., ?
      Ubiquitous computing: smart devices, environments and interaction
    • Tagging Applications: Automated Physical Access Ubiquitous computing: smart devices, environments and interaction
    • Tagging Applications: Asset Tracking Ubiquitous computing: smart devices, environments and interaction
    • Tagging Applications: Security Ubiquitous computing: smart devices, environments and interaction
    • Physical versus Virtual Tags Ubiquitous computing: smart devices, environments and interaction
    • Life-cycle for Tagging Physical Objects Ubiquitous computing: smart devices, environments and interaction
    • Design issues for Anchoring Tags on Physical Objects
      • Different ways to characterise and classify tagging
      • By how to augment physical world objects for use in virtual (computer) environments
      • By use of Onsite versus Offsite and attached versus detached classification of tags
      Ubiquitous computing: smart devices, environments and interaction
    • Augment physical environments for use in virtual environments
      • Augment the user:
      • Augment the physical object:
      • Augment the surrounding environment:
      Ubiquitous computing: smart devices, environments and interaction
    • Onsite versus Offsite & Attached versus Detached Annotation
      • 2 dimensions:
      • User of the annotation is
        • onsite (co-located or local) with physical object versus
        • offsite (not co-located or remote).
      • Annotation is
        • attached (or augments) physical object it refers to versus
        • being detached (not augmented or not collocated) with the physical object.
      Ubiquitous computing: smart devices, environments and interaction
    • Onsite versus Offsite & Attached versus Detached Annotation Ubiquitous computing: smart devices, environments and interaction Offsite Onsite Attached Detached
    • Design issues for Anchoring Tags on Physical Objects Ubiquitous computing: smart devices, environments and interaction
    • Design issues for Tagging Physical environment
      • Tags read outdoors in noisy, wet, dark or bright environments.
      • Annotation data storage, distribution & integration with data
      • Data management must start as soon as the data is captured (readers).
      • Multiple tags & readers per unit Vol..
        • Challenges?
      • Redundant annotations: similar items are captured, many times over.
        • Solutions?
      • Applications and businesses need to define the level of aggregation, reporting, analysis
      Ubiquitous computing: smart devices, environments and interaction
    • RFID Tags
      • A type of on-site tag, attached to physical object
      • RFID (Radio Frequency Identifier) Tags, attached to objects to enable identification of objects in the world over a wireless link.
      • RFID Tags versus Bar codes?
      Ubiquitous computing: smart devices, environments and interaction
    • RFID Tags: Applications
      • ???
      Ubiquitous computing: smart devices, environments and interaction
    • Types of RFID Tag
      • RFID tags may be classified into whether or not they:
        • Active:
        • Passive:.
      • Active tags are more expensive and require more maintenance but have a longer range compared to passive tags.
      • Typical RFID system main components:
      • tag itself, reader, data storage, post-processing
      • RFID tag versus RF Smart Card?
      Ubiquitous computing: smart devices, environments and interaction
    • Active RFID Tags
      • Active RFID tags used on large, more expensive assets
      • .
      • Typically operate at 0.455, 2.45 or 5.8 GHz frequencies
      • Have a read range of 20 M to 100 M,
      • Cost?
      • Complex active tags could also incorporate sensors. How? Why?
      • 2 types of active tags: transponders and beacons
      Ubiquitous computing: smart devices, environments and interaction
    • Active RFID Transponders
      • Active transponders are woken up when they receive a signal from a reader.
      • Transponders conserve battery life. How?
      • Important application of active transponders is in toll payment collection, checkpoint control and other systems.
      Ubiquitous computing: smart devices, environments and interaction
    • Active RFID Beacons
      • Main difference c.f. Transponder is long range, global? beacon reader
      • Beacons are used in Real-Time Location Systems (RTLS)
      • Longer range RTLS could utilise GPS or mobile phone GSM trilateration
        • See Chapter 7
      • In RTLS, a beacon emits a signal with its unique identifier at pre-set intervals
      Ubiquitous computing: smart devices, environments and interaction
    • Active RFID Transponder Application: toll booths Ubiquitous computing: smart devices, environments and interaction
    • Passive RFID Tags
      • Contain no power source and no active transmitter
      • Power to transmit comes from where?
      • Cheaper than active tags, cost?
      • Shorter (read access) range than active tags, typically ??
      • Passive RFID transponder consists of a microchip attached to an antenna, e.g., same as smart card
      • Lower maintenance
      • Passive Transponders can be packaged in many different ways,
        • ????
      Ubiquitous computing: smart devices, environments and interaction
    • Passive RFID Tags
      • Passive tags typically operate at lower frequencies than active tags
      • Low-frequency tags are ideal for applications where the tag needs to be read through certain soft materials and water at a close range. Why?
      Ubiquitous computing: smart devices, environments and interaction
    • Passive Tags: Near Field
      • 2.different approaches to transfer power from the reader to passive tags: near field and far field
      • Near field
      • Passive RFID interaction based upon electromagnetic induction.
      • Explain how this works here
      Ubiquitous computing: smart devices, environments and interaction
    • Passive Tags: Far Field
      • Why can’t electromagnetic induction be used?
      • So how does far field RFID interaction work?
      Ubiquitous computing: smart devices, environments and interaction
    • Business Use of Annotation
      • Physical artefact annotation is often driven by business goals.
      • Uniquely identify objects from manufacture during business processes
      Ubiquitous computing: smart devices, environments and interaction
    • Personal use of Annotation
      • Tags are less specific, deterministic, multi-modal (using multiple sensory channels) using multimedia.
      • Subjective annotations are used in multiple contexts, multiple applications and multiple activities by users.
      • Semantic gap challenge: between the low-level object features extracted and their high-level meaning with respect to a context of use
      • Several projects to tag personal views of physical world
        • MyLifeBits
        • Semacode
        • Google Earth? But Is it personalised?
        • etc
      Ubiquitous computing: smart devices, environments and interaction
    • Personal use of Annotation: Semacode
      • Semacode (2005) propose a scheme to define labels that can be automatically processed from captured images and linked to a Web-based spatial information encyclopaedia.
      • How does a semacode encodes URLs??
      • How to create a semacodes?
      • How do read a Semacaode
      • Some management may be needed to control malicious removal, movement and attachment.
      Ubiquitous computing: smart devices, environments and interaction
    • Semacode Use Ubiquitous computing: smart devices, environments and interaction
    • Overview
      • Introduction
      • Tagging the Physical World
      • Sensors and Sensor Networks 
      • Micro Actuation and Sensing: MEMS
      • Embedded Systems and Real-time Systems
      • Control Systems (For Physical World Tasks)
      • Robots
      Ubiquitous computing: smart devices, environments and interaction
    • Sensors: introduction
      • Sensors are transducers that convert some physical phenomenon into an electrical signal
      • Wireless sensors:
      • Sensors can be networked – sensor nets
      Ubiquitous computing: smart devices, environments and interaction
    • Sensor Applications
      • Give some examples of sensor use
      • Cars
      • Computers
      • Retail, logistics:
      • Household tasks
      • Buildings
      • Environment monitoring
      • Industrial sensing & diagnostics
      Ubiquitous computing: smart devices, environments and interaction
    • Sensors Types
      • Sensors can be characterised according to:
      • Passive (tags) vs. active
      • Single sensors vs sensor arrays vs sensor nets
      • Read-only program vs. re-programmable
      Ubiquitous computing: smart devices, environments and interaction
    • Sensors versus Tags
      • ???
      Ubiquitous computing: smart devices, environments and interaction
    • Ubiquitous computing: smart devices, environments and interaction
    • Sensor Nets
      • Main components of a typical sensor network system are networked sensors nodes serviced by sensor access node.
      • Slightly different but compatible view of a sensor network is to view sensors as being of three types of node):
        • common nodes
        • sink nodes
        • gateway (access)
      • In scenario given earlier, some sensors in the network can act as sink nodes within the network in addition to the access node.
      • Concepts of sensor node & sensor net can be ambiguous:
        • A sensor can act as a node in a network of sensors versus there is a special sensor network server often called a sensor (access) node
      Ubiquitous computing: smart devices, environments and interaction
    • Sensor Net: Functions
      • The main functions of sensor networks can be layered in a protocol stack according to:
        • physical network characteristics,
        • data network characteristics
        • data processing and sensor choreography
      • Use small network protocol stack for sensor nets. Why?
      • Other conceptual protocol layered stacks could also be used instead to model sensor operation,
      Ubiquitous computing: smart devices, environments and interaction
    • Sensor Net: Functions Ubiquitous computing: smart devices, environments and interaction
    • Sensors: Electronics
    • Sensor Net Design: Signal Detection & Processing
      • Positioning & coverage of networks is important. Why?
      Ubiquitous computing: smart devices, environments and interaction
    • Sensor Net Design: Positioning & Coverage
      • Given: sensor field (either known sensor locations, or spatial density)
        • Where to add new nodes for max coverage?
        • How to move existing nodes for max coverage?
      • Can Control
        • Area coverage:
        • Detectability:
        • Node coverage:
      Ubiquitous computing: smart devices, environments and interaction
    • Sensor Net Design: Improved SNR Through Using Denser Sensor Nets
      • Sensor has finite range determined by base-line (floor) noise level
      • Denser sensor field improves detection of signal source within range. How?
      Ubiquitous computing: smart devices, environments and interaction
    • Overview
      • Overview: Sensor Net Components & Processes
      • Physical Network: Environment, Density & Transmission
      • Data Network: Addressing and Routing 
      • Data Processing: Distributed Data Storage & Data Queries
      Ubiquitous computing: smart devices, environments and interaction
    • Senor Net Design: Sensor Data Routing
      • Networking sensors versus networking computers?
      • Sensors form P2P network with a mesh topology network
      • Sensors are massively distributed and work in real-time
      • No universal routing protocols or central registry.
      • Each node acts a router and application host.
      Ubiquitous computing: smart devices, environments and interaction
    • Sensor Routing
      • Make sensor address resolution efficient
      • Data centric routing,
        • Directed Diffusion
        • Flooding
        • Gossiping
      • Routing classification
        • Network structure: flat, hierarchical, hybrid
        • By interaction protocol
      Ubiquitous computing: smart devices, environments and interaction
    • Sensor Networks vs. Ad Hoc Networks
      • ???
      Ubiquitous computing: smart devices, environments and interaction
    • Sensor Net Topologies
      • ??
      Ubiquitous computing: smart devices, environments and interaction
    • Senor Net Design: I n-Network Processing
      • Why perform I n-Network Processing?
      Sensor Node Sensors Ubiquitous computing: smart devices, environments and interaction
    • Sensor Net: Data Storage & Retrieval
      • What designs/ architectures can we use for sensor net data storage an retrieval?
      Ubiquitous computing: smart devices, environments and interaction
    • Sensor Database System
      • Characteristics of a Sensor Network:
      • Can existing database techniques be reused?
      Ubiquitous computing: smart devices, environments and interaction
    • Sensor Net: Technologies, Kits & Standards
      • Sun Spot: Java
      • Berkeley Motes: TinyOS, C
      • SPINE (Signal Processing in Node Environment)
      • OGC Standards: SensorML etc
      Ubiquitous computing: smart devices, environments and interaction
    • Overview
      • Introduction
      • Tagging the Physical World
      • Sensors and Sensor Networks
      • Micro Actuation and Sensing: MEMS 
      • Embedded Systems and Real-time Systems
      • Control Systems (For Physical World Tasks)
      • Robots
      Ubiquitous computing: smart devices, environments and interaction
    • Micro Actuation and Sensing: MEMS
      • Fabrication
      • Micro-Actuators
      • Micro-Sensors
      • Smart Surfaces, Skin, Paint, Matter and Dust
      • Downsizing to Nanotechnology and Quantum Devices
      Ubiquitous computing: smart devices, environments and interaction
    • Trend: Miniaturisation
      • Electronic components become smaller, faster, cheaper to fabricate, lower power & lower maintenance, they can be more easily deployed on a massive and pervasive scale.
      • MicroElectro Mechanical Systems ( MEMS ) are based upon IC Chip design
      • Possibilities for miniaturization extend into all aspects of life, & potential for embedding computing & comms technology quite literally everywhere is becoming a reality.
      • IT as an invisible component in everyone's surroundings
      • Extending the Internet deep into the physical environment
      Ubiquitous computing: smart devices, environments and interaction
    • Trend:  IC Transistor Density
      • Gordon Moore (1965), Intel co-founder made a prediction, now popularly known as Moore's Law, which states that the number of transistors on an IC chip doubles ~ every 2 y
      • Does it mean that software processing capability will also increases in this way?
      •  IC Chip density =  Software Performance?
      Ubiquitous computing: smart devices, environments and interaction
    • MEMS: Introduction
      • MEMS (Micro-electromechanical systems): micron- to millimetre-scale electronic devices fabricated as discrete devices or in large arrays
      • MEMS perform 2 basic types of functions: sensors or actuators.
      • Both act as transducers converting one signal into another.
      • MEMS actuators: electrical signal -> physical phenomena to move or control mechanisms.
      • MEMS Sensors work in reverse to actuators
      Ubiquitous computing: smart devices, environments and interaction
    • MEMS Examples Electrostatic motor Actuator Hinge Gyroscope Ubiquitous computing: smart devices, environments and interaction
    • MEMS: Fabrication
      • MEMS comprising mechanical and discrete electronic components
      • MEMS design is different from macro devices
      • MEMS design are based upon IC chips design
      • Silicon based materials have:
        • Well understood electrical properties
        • Good mechanical properties
      Ubiquitous computing: smart devices, environments and interaction
    • MEMS: Fabrication
      • Design a new circuit = design of interconnections among millions of relatively simple and identical components.
      • Diversity and complexity of the interconnections -> diversity of electronic components including memory chips and CPUs.
      • Multiplicity, batch fabrication, is inherent.
      • Miniaturisation of IC based MEMS processing has important advantages over macro electromechanical devices and systems?
      Ubiquitous computing: smart devices, environments and interaction
    • MEMS : Fabrication
      • Micromachines are fabricated just like ICs.
      • MEMS type ICs can be fabricated in different ways using:
        • Bulk micro-machining
        • Surface micro-machining
        • LIGA deep structures.
      Ubiquitous computing: smart devices, environments and interaction
    • Micro-Actuator
      • Mechanisms involved in micro-actuation whilst conceptually similar to equivalent macro mechanisms may function fundamentally differently,
      • Are engineered in a fundamentally different way using IC
      Ubiquitous computing: smart devices, environments and interaction
    • Micro-actuator: Applications
      • Micro-mirrors, e.g., ??
      • Micro-fluid pumps, e.g., ??
      • Miniature RF transceivers, e.g., ??
      • Miniature Storage devices, e.g., ??
      • Etc
      Ubiquitous computing: smart devices, environments and interaction
    • Micro-sensors
      • Sensors are a type of transducer
      • Microsensors can work quite differently from equivalent macro sensor,
      • Sensors enable adaptation
      • Often embedded into system as part of a control loop
      Ubiquitous computing: smart devices, environments and interaction
    • MEMS: Applications
      • Micro-accelerometers,
        • E.g., ??
      • Micro-gyroscopes
        • E.g.,
      • Detecting Structural Changes
        • E.g.,
      Ubiquitous computing: smart devices, environments and interaction
    • Smart Device Form Factors: Smart Dust, Skins & Clay
      • 3 forms proposed by Weiser (1 tabs, 2 pads & 3 boards) can be extended to include 3 more forms:
      • Smart Dust :
      • Smart Skins :
      • Smart Clay :
      Ubiquitous computing: smart devices, environments and interaction
    • Smart Dust: MEMS
      • MEMS can be sprayed into physical environment
      • E.g., Smart Dust project (Pister, UC,Berkely)
      • (see Chapter 2)
      Ubiquitous computing: smart devices, environments and interaction
    • Smart Skins: MEMS
      • MEMS can be permanently attached to some fixed substrate forming
        • smart surfaces
        • smart skin
      • E.g. Paint that is able to sense vibrations
      • See also Organic Displays (Chapter 5)
      Ubiquitous computing: smart devices, environments and interaction
    • Smart Clay: MEMS
      • Claytronics project
      • Can behave as malleable programmable matter
      • Are MEMS ensembles
      • Self-assembled into any arbitrary 3D shape
      • Goal to achieve a synthetic reality.
      Ubiquitous computing: smart devices, environments and interaction
    • MEMS: Challenges
      • Establishing ownership of all of these micro items.
      • Coping with data overload
      • Different Low-level patterns of signals may be ambiguous and variable.
      • Handling context switches between these augmented environment events via assisted senses and the unassisted ones.
      • Are micro-devices either easy to dispose of or hard to dispose of?
        • What is we swallow / breath them in?
      • How to manage MEMS?
        • See Chapter 12
      Ubiquitous computing: smart devices, environments and interaction
    • Nanocomputing
      • Nanocomputing can be defined as the manipulation, precision placement, measurement, modelling, and manufacture to create systems with less than 100 nm
      • Also referred to as nanotechnology
      • Is based upon a broader range of materials, mechanisms & sizes down to molecular level
      • MEMS Vs. Nanocomputing?
      Ubiquitous computing: smart devices, environments and interaction
    • Nanocomputing
      • The drive to switch transistors faster and to be low-powered has been to make them smaller.
      • When electronic components approach nanometer sizes, odd things begin to happen. What?
      • This raised an early concern about the feasibility of nanotechnology.
      • Other challenges are:
      • thermal noise
      • positioning and the control of structures at this level
      Ubiquitous computing: smart devices, environments and interaction
    • Nanocomputing
      • Nanotechnology at first proposed to use a bottom-up approach to design, to be able to assemble custom-made molecular structures for specific applications,
      • A major challenge to this design process is the complexity and novelty in understanding and being able to model materials at this level.
      • More research is needed to understand how combinations of materials, in particular compounds, gives materials at the molecular level certain physical and functional properties..
      Ubiquitous computing: smart devices, environments and interaction
    • Overview
      • Introduction
      • Tagging the Physical World
      • Sensors and Sensor Networks
      • Micro Actuation and Sensing: MEMS
      • Embedded Systems and Real-time Systems 
      • Control Systems (For Physical World Tasks)
      • Robots
      Ubiquitous computing: smart devices, environments and interaction
    • Embedded Systems: Introduction
      • Is a component in a larger system
      • Is programmable
      • Performs a single, dedicated task.
      • May or may not be visible as a computer to a user of that system
      • May or may not have a visible control interface
      • E.g., ???
      • May be local or remote,
        • e.g., ??
      • fixed or mobile
        • e.g??
      Ubiquitous computing: smart devices, environments and interaction
    • Embedded System Characteristics (Embedded vs. MTOS Systems)
      • Traditionally, embedded systems differ from MTOS systems
      • OS of Embedded systems differ vs. MTOS system
      • Specialised to single task enactment (ASOS)
      • Actions on physical world tasks are often scheduled with respect to real-time constraints (RTOS)
      • Safety-criticality is considered more important
      Ubiquitous computing: smart devices, environments and interaction
    • Embedded vs. MTOS Systems
      • Often have constraints concerning power consumption
      • Often are designed to operate over a wide-range of physical environmental conditions compared to PC
        • e.g.,
      • Often operate under moderate to severe real-time constraints.
      • System failures can have life-threatening consequences.
        • E.g.,
      Ubiquitous computing: smart devices, environments and interaction
    • Embedded vs. MTOS Systems
      • Each embedded computing devices may be designed for its own rigidly defined operational bounds
        • e.g.,
      • Linking embedded systems to external systems
      • Designs often engineered for a trade-off
      • Fewer system resources then PC. How?
      • Embedded systems not always easy to programme. Why?
      • Most embedded designs (hardware & software) are unique
      • Use a far simpler & cheaper OS & hardware. Why?
      Ubiquitous computing: smart devices, environments and interaction
    • Embedded Systems: Hardware
      • Microprocessors
      • Microcontroller
      • FPGA (Field Programmable Gate Arrays):
      Ubiquitous computing: smart devices, environments and interaction
    • Real-Time System (RTS)
      • Real-time systems (RTS) can be considered to be resource-constrained
      • Often RTS perform safety-critical tasks
      • RTS reacts to external events that interrupt it:
      • RTS uses mechanisms for priority scheduling of interrupts
      • RTOS may also use additional process control:
        • .
      Ubiquitous computing: smart devices, environments and interaction
    • RTS Design Concerns
      • There are a range of real-time design concerns to support critical response time of a task:
      • Need to optimise
        • both response time and data transfer rate
        • optimising these when there are simultaneous tasks.
      • Key factors that affect the response time are?
        • process context-switching
        • interrupt latency
      Ubiquitous computing: smart devices, environments and interaction
    • RTS: Hard vs. Soft
      • Timeliness is single most important aspect of RT system.
      • RTS system is one where timing of result is just as important as the result itself.
      • A correct answer produced too late is just as bad as an incorrect answer or no answer at all.
      • RTS correctness of computations not only depends upon the logical correctness of the computation but also upon time to produce results.
      • If the timing constraints are not met, system failure occurs
      • Timing constraints can vary between different real-time systems.
      • Therefore, RTS can fall into one of three categories: soft, hard or firm..
      Ubiquitous computing: smart devices, environments and interaction
    • RTS: Soft
      • Single computation arriving late may not be significant to the operation of the system,
        • Although many late arrivals might be significant
      • Timing requirements can be defined by using an average response time.
      Ubiquitous computing: smart devices, environments and interaction
    • RTOS: Hard
      • Timing requirements are vital.
      • Response that’s late is incorrect and system failure results.
      • Activities must complete by specified deadline, always.
      • Different types of deadlines. What?
      • If a deadline is missed the task fails
        • E.g., ??
      • This demands that the system has the ability to predict how long computations will take in advance.
      Ubiquitous computing: smart devices, environments and interaction
    • Safety-Critical Systems
      • Instructors could add some text here or delete this slide.
      Ubiquitous computing: smart devices, environments and interaction
    • Overview
      • Introduction
      • Tagging the Physical World
      • Sensors and Sensor Networks
      • Micro Actuation and Sensing: MEMS
      • Embedded Systems and Real-time Systems
      • Control Systems (For Physical World Tasks) 
      • Robots
      Ubiquitous computing: smart devices, environments and interaction
    • Links to other Topics
      • Control systems / robots can be simple, operate in static deterministic environments.
      • To operate in more dynamic non- deterministic environments, they can make use of AI techniques (Chapters 8-10).
      • HCI aspects of (biologically inspired) robots such as affective computing etc (Chapter 5)
      Ubiquitous computing: smart devices, environments and interaction
    • Control Systems (For Physical World Tasks)
      • Simply type of control
        • Activated only when defined thresholds are crossed,
        • e.g., .
      • Disadvantages?
      • Solutions?
      Ubiquitous computing: smart devices, environments and interaction
    • Control Systems: Feedback Control
      • 2 basic kinds of feedback:
        • negative
        • positive
      • Negative feedback
      • Seeks to reduce some change in a system output or state
      • Based upon derivative of output
      • Which is then used to modify input to regulate output.
      • Several types of feedback control: D, P, I, PID
      • Positive feedback
      • Acts to amplify a system state or output
      Ubiquitous computing: smart devices, environments and interaction
    • Control Systems: Derivative (D) Feedback Control Ubiquitous computing: smart devices, environments and interaction
    • Control Systems: Proportional (P) Feedback Control
      • In simple proportional (-ve feedback) control system
      • Action taken to negatively feedback a signal to the plant,
      • Is in proportion to the degree the system diverges from the reference value
      • This leads to a much smoother regulation
        • e.g.,.
      Ubiquitous computing: smart devices, environments and interaction
    • Control Systems: PID Controllers
      • Sometimes P type controller output is not regulated correctly
        • e.g., ??
      • To solve this problem either integral or differential control or both can be added to the control.
      • PID controller is so named because it combines Proportional, Integral and Derivative type control
      • Proportional (P) controller is just the error signal multiplied by a constant and fed out to a hardware drive.
      Ubiquitous computing: smart devices, environments and interaction
    • Control Systems: PID Controllers
      • Integral (I) controller deals with past behaviour of control.
      • Derivative (D) type controller is used to predict the plant behaviour
      • P, PI, PD or PID control are often simple enough, to be hard-coded into controllers
      • Usually support some adjustment controls,
        • e.g.,
      • PID controllers can be designed to be programmable
      Ubiquitous computing: smart devices, environments and interaction
    • PID Controllers Ubiquitous computing: smart devices, environments and interaction
    • Programmable Controllers: Microcontrollers
      • Hardware architecture of microcontrollers is much simpler than general purpose processor mother-boards in PCs?
      • I/O control support can be simpler as there may not be any video screen output or keyboard input.
      • Micro-controllers can range in complexity
      • Originally, programmed in assembly language, later in C
      • Control programs often developed in an emulator on a PC
      • More recent microcontrollers can be integrated with on-chip debug circuitry accessed by an in-circuit emulator
      Ubiquitous computing: smart devices, environments and interaction
    • Complex Control Systems
      • PID control Useful for coarse-gained, static control
        • E.g., palletising, coarse-controlled locomotion, etc
      • PID control not suitable for ?
        • fine-grained
        • dynamic control
        • uncertainties in control
      Ubiquitous computing: smart devices, environments and interaction
    • Complex Control
      • Several sources of uncertainty?
      • Techniques for controlling uncertain systems?
      Ubiquitous computing: smart devices, environments and interaction
    • Overview
      • Introduction
      • Tagging the Physical World
      • Sensors and Sensor Networks
      • Micro Actuation and Sensing: MEMS
      • Embedded Systems and Real-time Systems
      • Control Systems (For Physical World Tasks)
      • Robots 
      Ubiquitous computing: smart devices, environments and interaction
    • Robots
      • Early 1960s, robots started to be used to automate industrial tasks particularly in manufacturing
      • Why Automate?
      Ubiquitous computing: smart devices, environments and interaction
    • Main Robot Components
      • Robots consist of:
      • End effectors or actuators:
      • Locomotion:
      • Drive:
      • Controller
      • Sensor
      Ubiquitous computing: smart devices, environments and interaction
    • Robots: Localisation
      • Localisation is used to determine a robot’s position in relation to its physical environment.
      • Localisation can be local or global.
      • Local localisation is often simpler in which a robot corrects its position in relation to its initial or other current reference location.
      • Global localisation is discussed more in context-aware systems part.
      Ubiquitous computing: smart devices, environments and interaction
    • Robots: Types
      • 3 Main Types
      • Robot manipulator or robot arm
      • Mobile robots
      • Biologically inspired robots
      Ubiquitous computing: smart devices, environments and interaction
    • Robot Manipulators
      • A manipulator consists of a linked chain of rigid bodies that are linked in an open kinematic chain at joints.
      • rigid body can have up to 6 Degrees Of Freedom (DOF) of movement.
      • This comprises 3 translational DOF
        • ???
      Ubiquitous computing: smart devices, environments and interaction
    • Robot Manipulators
      • Also comprises 3 rotational DOF
        • ???
      • Joints are designed to restrict some DOF.
      • Human operators may be in the control loop of robot manipulators. Why?
      Ubiquitous computing: smart devices, environments and interaction
    • Robot Manipulators: Design
      • Motion planning needed
      • Control algorithms?
      • Regulation of contact force
      • Manipulators need to cope with variations in components and objects being manipulated. Solutions?
        • Use adaptive AI techniques (Chapter 8)
        • Put human in the control loop
      Ubiquitous computing: smart devices, environments and interaction
    • Mobile Robots
      • Mobile robots use various kinds of locomotion systems
        • ?
      • Simplest types of mobile robots to control
        • ??
      • In dynamic non-deterministic environments, control is more complicated
      • A more complex, well-known & highly successful use of mobile robots was Mars Explorer Robots
      Ubiquitous computing: smart devices, environments and interaction
    • Mobile Robots
      • No. of DOF is often less compared to a robot manipulator.
      • Need ways to navigate obstacles?
      • Simple approach: use collision detection
      • More complex approach: anticipate & avoid collisions
        • Need environment models (AI, Chapter 8)
        • Need to replan paths to reach goal destinations (AI, Chapter 8)
      Ubiquitous computing: smart devices, environments and interaction
    • Biologically Inspired Robots: Legged locomotion
      • Biologically inspired robots are more complex type of robot
        • Combines legged locomotion capabilities & manipulator
      • 2 main focuses to these robots:
        • Legged locomotion (in combination with manipulator)
        • Human-Robot Interaction
      Ubiquitous computing: smart devices, environments and interaction
    • Biologically Inspired Robots: Legged locomotion
      • The use of legs enables legged robots to travel over irregular terrain
      • Biped robots often have more DOF than either the mobile robot or robot manipulator
      • Particular design challenge for biped robots is stability
      Ubiquitous computing: smart devices, environments and interaction
    • Biologically Inspired Robots: Human Robot Interaction
      • Human robot Interaction:
        • a specialisation of HCI, see Chapter 5
      • Robots can assist humans and extend sensing capabilities of (less able?) humans – Posthuman model.
      • Robots can fulfil social roles
        • i.e., affective computing (Chapter 5)
        • e.g., artificial pets
      • Social guided learning
        • Learning by imitation or by tutelage
      • Use of more human oriented interface & interaction
        • E.g., speech recognition
      Ubiquitous computing: smart devices, environments and interaction
    • Nanobots
      • Nanobots can be manufactured as MEMS or at molecular level.
      • Microscopic world is governed by the same physical laws as the macroscopic world
      • But relative importance of the physical laws change in how it affects the mechanics and the electronics at this scale
      Ubiquitous computing: smart devices, environments and interaction
    • Nanobots
      • Nature in terms of micro-organisms can be harnessed in order to provide a host body for nanobots to move about
        • e.g.,
      • Shrinking device size to these nano dimensions leads to many interesting challenges:
      Ubiquitous computing: smart devices, environments and interaction
    • Developing UbiCom Robot Applications
      • Industrial types of robots
      • Low cost consumer type robots
      • Robots toolkits that are programmable.
      Ubiquitous computing: smart devices, environments and interaction
    • Ultrasonic Sensor Light Sensor Motor A Motor B Motor C Ubiquitous computing: smart devices, environments and interaction
    • Developing UbiCom Robot Applications
      • Task: robot manipulates a Rubik’s Cube to its solved state
      • Goal: robot performs whole task or guides humans to do it
      • Design involves
      • Design: of the robot mechanics
      • Design: how and when the robot senses state of the world
        • e.g. ,
      • Planning algorithm: to link individual actions
      • Overall architecture: to integrate different sub-tasks
        • e.g.,
      Ubiquitous computing: smart devices, environments and interaction
    • Developing UbiCom Robot Applications
      • Several practical issues for physical robots tasks execution
      • Sensor accuracy
      • Position accuracy
      • Variable amounts of friction during movement
      • Some elasticity in the robot arm
      • Low-level design to tell robots to carry out specific tasks
      • Tasks need to be designed to fit the robots capabilities
      • In open physical world, much non-determinism to handle
      • -> There does not yet exist, flexible general purpose UbiCom robots, which can act as autonomous assistants or servants for mass human use.
      Ubiquitous computing: smart devices, environments and interaction
    • Overview
      • Introduction 
      • Tagging the Physical World 
      • Sensors and Sensor Networks 
      • Micro Actuation and Sensing: MEMS 
      • Embedded Systems and Real-time Systems 
      • Control Systems (For Physical World Tasks) 
      • Robots 
      Ubiquitous computing: smart devices, environments and interaction
    • Summary & Revision
      • For each chapter
      • See book web-site for chapter summaries, references, resources etc.
      • Identify new terms & concepts
      • Apply new terms and concepts: define, use in old and new situations & problems
      • Debate problems, challenges and solutions
      • See Chapter exercises on web-site
      Ubiquitous computing: smart devices, environments and interaction
    • Exercises: Define New Concepts
      • Annotation
      Ubiquitous computing: smart devices, environments and interaction
    • Exercise: Applying New Concepts Ubiquitous computing: smart devices, environments and interaction
    • Supplementary Slides
      • Exercises & Solutions
      Ubiquitous computing: smart devices, environments and interaction
    • Sensor Applications
      • Ex: Give some examples of sensor use
      • Cars: air pressure, brake-wear, car-doors, engine etc
      • Lap-top: accelerometers – switch off computer disks when dropped
      • Retail, logistics: RFIDs
      • Heaters: thermostats
      • Infrastructure protection / Intrusion detection (active sensors)
      • Environment monitoring
      • Industrial sensing & diagnostics
      • Battlefield awareness
      • Sensors can be characterised according to:
        • passive (tags) vs. active
        • Single sensors vs sensor arrays vs sensor nets
        • Read-only program vs. re-programmable
      Ubiquitous computing: smart devices, environments and interaction