1 / 28

Enhancing Wireless Solutions for Factory Automation Proposal

This submission by Siemens AG presents a proposal to amend IEEE 802.15.4-2006 for wireless sensor/actuator networks used in factory automation, focusing on improving determinism, reliability, and latency for optimal performance in factory settings. The document outlines the motivation, MAC solution, and considerations for both factory and process automation, emphasizing the benefits of using the same wireless communication technology across related but independent use cases. The proposed enhancements aim to address the specific requirements of factory automation, such as high determinism, reliability, low latency, and network management for improved co-existence with IEEE 802.11 WLAN.

garcias
Download Presentation

Enhancing Wireless Solutions for Factory Automation Proposal

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Proposal for Factory Automation ] Date Submitted: [ 31 August, 2008 ] Source: [ Ludwig Winkel, Michael Bahr, Norbert Vicari ] Company [ Siemens AG] Address [Siemensallee 74, Karlsruhe, Germany] Voice:[+49-721-595 6098], FAX: [+49-721-595 893 6098], E-Mail:[ludwig.winkel@siemens.com] Re: [response to Call for Proposals doc 15-08/0373r1] Abstract: [ Proposal to IEEE 802.15.4e for wireless sensor/actuator networks applicable for factory automation.] Purpose: [amending 802.15.4-2006 for matching the requirements for factory automation] Notice: This document has been prepared to assist the IEEE P802.15. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15. M. Bahr, N. Vicari, L. Winkel, Siemens AG

  2. Proposal for Factory Automation Michael Bahr (Siemens AG) Norbert Vicari (Siemens AG) Ludwig Winkel (Siemens AG) presentation 15-08/0571r0 text 15-08/0572r0 M. Bahr, N. Vicari, L. Winkel, Siemens AG

  3. Overview • Support of factory automation and process automation • Proposal for Factory Automation • Motivation • Proposed MAC solution • Considerations for Process Automation • Mesh Support M. Bahr, N. Vicari, L. Winkel, Siemens AG

  4. Support of Process Automation and Factory Automation • process automation (PA) and factory automation (FA) are related but quite inde-pendent use cases with different requirements • use of same wireless communication technology (IEEE 802.15.4) is beneficial • configurability of IEEE 802.15.4e • common base functionality • configurable for process automation use cases • configurable for factory automation use cases M. Bahr, N. Vicari, L. Winkel, Siemens AG

  5. MAC Proposal for Factory Automation M. Bahr, N. Vicari, L. Winkel, Siemens AG

  6. automotive robots suspension tracks portable machine tools milling, turning robot revolver filling cargo airport logistics post packaging industry special engineering conveyor technique Use Cases of Factory Automation M. Bahr, N. Vicari, L. Winkel, Siemens AG

  7. high determinism high reliability low latency: transmission of sensor data in  10 ms low round-trip time many sensors per gateway might be more than 100 sensors per gateway assume controlled envi-ronment (factory floor) configuration for optimal performance network management and frequency planning for avoidance of co-existence issues Requirements and Assumptions M. Bahr, N. Vicari, L. Winkel, Siemens AG

  8. Why IEEE 802.15.4? • coexistence with IEEE 802.11 WLAN • 3 non-overlapping channels for IEEE 802.11 • 4 channels for IEEE 802.15.4 • sufficient range • worldwide acceptance • worldwide standard North America (similar worldwide) M. Bahr, N. Vicari, L. Winkel, Siemens AG

  9. star topology gateway devices sensors:unidirectional data exchange from devices to gateway actuators: bidirectional data exchange between devices and gateway Network Topology M. Bahr, N. Vicari, L. Winkel, Siemens AG

  10. General Concept • IEEE 802.15.4 PHY frames • Time Division Multiple Access • superframe with timeslots of fixed length • shared group timeslots with CSMA • addressing based on timeslot location or short address • modified MAC frame • Roaming capability (no channel hopping) M. Bahr, N. Vicari, L. Winkel, Siemens AG

  11. Time Division Multiple Access • Superframe • starts with beacon • followed by n timeslots of equal, fixed length • Timeslots • one device per timeslot (dedicated timeslot) • determinism • (re-)synchronization through beacon • allows sleep mode / power save of devices M. Bahr, N. Vicari, L. Winkel, Siemens AG

  12. Shared Group Timeslots • more than one device per timeslot • carrier sense multiple access within shared group timeslot • 1 or more continuous timeslots concatenated to a shared group timeslot • all timeslots in single shared group timeslot  network with carrier sense multiple access • mixture between fixed, deterministic timeslots and shared group timeslots possible M. Bahr, N. Vicari, L. Winkel, Siemens AG

  13. Structure of Superframe • existence of management timeslots configurable during setup • number of (timeslots for) sensors and actuators configurable during setup M. Bahr, N. Vicari, L. Winkel, Siemens AG

  14. MAC Frame Format • implicit addressing through slot number • omits MAC address fields in MAC header • very short MAC header of 1 byte • very short PSDU increases efficiency dramatically • turnaround time / latency main criteria • every byte counts: • data payload is very short • assume 1 byte data payload • 3 more bytes mean a 30% increase in latency! • FCS for error recognition M. Bahr, N. Vicari, L. Winkel, Siemens AG

  15. Frame Type corresponds to frame type subfield of IEEE 802.15.4-2006 set to b100 indicates frames with shortened MAC header Sub Frame Type indicates frame type with shortened MAC header beacon, command, ack, data frame Shortened Frame Control M. Bahr, N. Vicari, L. Winkel, Siemens AG

  16. Transmission modes • 3 transmission modes • Discovery • Configuration • Online • Transmission mode is signalled in beacon M. Bahr, N. Vicari, L. Winkel, Siemens AG

  17. Beacon Frame Payload • Online Mode • Discovery / Configuration Mode M. Bahr, N. Vicari, L. Winkel, Siemens AG

  18. Discovery mode • First step in network setup (addition of new devices) • Device sends its current configuration to gateway till ACK M. Bahr, N. Vicari, L. Winkel, Siemens AG

  19. Configuration mode • Second step in network setup • Used for re-configuration of network • Gateway sends new configuration to device M. Bahr, N. Vicari, L. Winkel, Siemens AG

  20. Online mode • Exchange of sensor data from sensors to gateway M. Bahr, N. Vicari, L. Winkel, Siemens AG

  21. Configurable parameters • Short MAC address • Structure of superframe (management time slots, sensor time slots, actuator time slots) • Number of time slots • Duration of time slots • Shared group time slots • Assigned time slots • Transmission channel M. Bahr, N. Vicari, L. Winkel, Siemens AG

  22. Online mode • Transmission of the actual data for factory automation (productivity data) • Gateway acknowledges receipt of data from sensors in beacon • Gateway signals direction of transmission for actuator timeslots in beacon • Transmission with or without acknowledgement or with block acknowledgement M. Bahr, N. Vicari, L. Winkel, Siemens AG

  23. Use of Single Channel • Operation under the assumption of wireless channel planning • Avoids „unproductive“ channel switch times • allows addressing by timeslot • Better support of roaming(e.g. conveyor belts) • Very good coexistence with other wireless networks (e.g. WLAN on different channels) M. Bahr, N. Vicari, L. Winkel, Siemens AG

  24. Considerations on Process Automation see also 15-08/409r2 M. Bahr, N. Vicari, L. Winkel, Siemens AG

  25. Mesh support • Applicable for process automation • IEEE 802.15.4 header extensions for mesh support • Additional addresses (source, destination) • Sequence number • TTL („transmissions to live“) • Framework for chosing path selection mechanisms • Path selection protocol • Link metrics M. Bahr, N. Vicari, L. Winkel, Siemens AG

  26. Frame forwarding • Received frames for other nodes are forwarded to the next hop according to aquired forwarding information • Frame forwarding capability required, realization implementation specific M. Bahr, N. Vicari, L. Winkel, Siemens AG

  27. Summary • Configurable distinction between factory automation and process automation • Propose highly efficient TDMA-based MAC scheme for factory automation • IEEE 802.15.4 PHY • very short latency through short data packets in short dedicated timeslots of fixed length • shared group timeslots • configurability • Mesh support for process automation M. Bahr, N. Vicari, L. Winkel, Siemens AG

  28. References • 15-08/0503r0 Preliminary Proposal for Factory Automation • presentation of preliminary proposal for factory automation at July 08 IEEE 802.15.4e meeting • 15-08/0571r0 Proposal for Factory Automation • presentation of proposal for factory automation at September 08 IEEE 802.15.4e meeting • 15-08/0572r0 Proposal for Factory Automation • text of proposal for factory automation M. Bahr, N. Vicari, L. Winkel, Siemens AG

More Related