UbiCom Book Slides

1. UbiCom Book Slides Chapter 6 Tagging, Sensing & Controlling Stefan Poslad http://www.eecs.qmul.ac.uk/people/stefan/ubicom Ubiquitous computing: smart devices, environmentsand interaction

2. 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

3. 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

4. Overview Chapter 6 focuses on: • internal system properties: context-awareness & autonomy • external interaction with the physical environment. Ubiquitous computing: smart devices, environments and interaction

5. 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

6. UbiCom Internal System Properties Ubiquitous computing: smart devices, environments and interaction

7. Smart Physical Environments Ubiquitous computing: smart devices, environments and interaction

8. Ubiquitous computing: smart devices, environments and interaction

9. 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

10. 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

11. 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

12. Tagging Applications: Automated Physical Access Ubiquitous computing: smart devices, environments and interaction

13. Tagging Applications: Asset Tracking Ubiquitous computing: smart devices, environments and interaction

14. Tagging Applications: Security Ubiquitous computing: smart devices, environments and interaction

15. Physical versus Virtual Tags Ubiquitous computing: smart devices, environments and interaction

16. Life-cycle for Tagging Physical Objects Ubiquitous computing: smart devices, environments and interaction

17. 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

18. 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

19. 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

20. Onsite versus Offsite & Attached versus Detached Annotation Attached Detached Offsite Onsite Ubiquitous computing: smart devices, environments and interaction

21. Design issues for Anchoring Tags on Physical Objects Ubiquitous computing: smart devices, environments and interaction

22. 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

23. 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

24. RFID Tags: Applications • ??? Ubiquitous computing: smart devices, environments and interaction

25. 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

26. 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

27. 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

28. 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

29. Active RFID Transponder Application: toll booths Ubiquitous computing: smart devices, environments and interaction

30. 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

31. 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

32. 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

33. 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

34. 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

35. 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

36. 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

37. Semacode Use Ubiquitous computing: smart devices, environments and interaction

38. 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

39. 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

40. 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

41. 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

42. Sensors versus Tags • ??? Ubiquitous computing: smart devices, environments and interaction

43. Ubiquitous computing: smart devices, environments and interaction

44. 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

45. 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

46. Sensor Net: Functions Ubiquitous computing: smart devices, environments and interaction

47. Sensors: Electronics

48. Sensor Net Design: Signal Detection & Processing Positioning & coverage of networks is important. Why? Ubiquitous computing: smart devices, environments and interaction

49. 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

50. 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