CANaerospace/AGATE data bus
(C) 2005 Stock Flight Systems page 1 of 26 What is the Controller Area Network (CAN) ?
¥ Two-wire multi-transmitter serial data bus
¥ Designed by Bosch in 1985 as automobile network
¥ No central bus controller required
¥ Configurable data rate (5kBit/s ... 1MBit/s)
¥ Bus length 0.2m to 10.000m (with linear data rate reduction)
¥ Realtime capabilities (guaranteed transmission times)
¥ Message oriented transmission (2031 message identifiers)
¥ Network wide data consistency through broadcasting principle
¥ > 200 bus participants
¥ More than 100 million nodes installed today
(C) 2005 Stock Flight Systems page 2 of 26 The major characteristics of CAN
¥ Effective data rate max. 576 kBit/s (<= 40m bus length) -> adequate for most realtime control systems ¥ No overhead for bus arbitration, known response times even for high bus loads -> bus performance independant of number of participants ¥ Extremely low probability of undetected data corruption (~ 1*10-13 per transmission) -> suitable for safety critical applications ¥ Very low chip cost, easy and straightforward application programming -> even small systems can benefit from network technology Due to these characteristics, CAN is used in several aircraft applications already and selected for many new aircraft: ¥ Grob Strato-2C High Altitude Research Aircraft: “throttle-by-wire” databus ¥ NH90 helicopter: Audio system intercommunication ¥ Airbus A340-600: Environmental control system databus, water&waste management ¥ Fairchild-Dornier 728JET: Primary/secondary flight control actuator databus, secondary power supply system intercommunication, smoke detection system databus ¥ A380: Environmental control system databus, cockpit cursor control device/MFD communication bus, electric power supply control databus, ......
(C) 2005 Stock Flight Systems page 3 of 26 CAN hardware
CAN controllers and Microcontrollers with integrated CAN interfaces:
¥ Motorola ¥ Intel ¥ Philips ¥ Infineon ¥ Toshiba ¥ NEC ¥ Texas Instruments, ..... CAN boards for various bus systems:
¥ VME ¥ PCI/PMC ¥ ISA/EISA ¥ SBus ¥ PC104/PC104+ ¥ IP, M-modules, PC-MIP, .....
(C) 2005 Stock Flight Systems page 4 of 26 CAN data rate vs. bus length
data rate (kBit/s) 1000
100
usable area
10
5 1040 100 1000 10000 bus length (m)
(C) 2005 Stock Flight Systems page 5 of 26 CAN and the ISO open systems interconnection reference model
user application
CAN Application Layer set of user-defined CANopen, DeviceNet, layer 7 (application layer) application functions CANaerospace, data representation, CAN Kingdom, .... layer 6 (presentation layer) data standardization, ... login, session dialog layer 5 (session layer) control, ... logical channels, data layer 4 (transport layer) transmission retries, ... routing, data packet layer 3 (network layer) flow control, ... error detection, layer 2 (data link layer) data block synchronisation, ... CAN 2.0/2.0A/2.0B connectors, cables, layer 1 (physical layer) voltage levels, ...
network
(C) 2005 Stock Flight Systems page 6 of 26 What is CANaerospace ?
¥ The CAN specification itself does not cover issues like data representation, station addressing or connection-oriented protocols.
¥ Using CAN networks in aerospace demands a standard targeted to the specific requirements of flight or mission critical airborne applications.
¥ Based on experience in flight control and guidance systems, Stock Flight Systems created the CANaerospace interface definition in 1997. CANaerospace is an open standard and may be used by anybody free of any charge. CANaerospace has also been standardized by the US National Air and Space Administration (NASA) as “AGATE data bus” in 2001 (document AGATE-WP01-001-DBSTD, Langley Research Center).
¥ CANaerospace is a slim software layer that turns CAN into an easy-to-handle data bus meeting the specific requirements of avionic systems.
¥ CANaerospace is used and supported by some major European aerospace companies (EADS, Eurocopter, Aero Vodochody, Rotax-Bombardier, Kayser-Threde, ....).
¥ CANaerospace networks are installed in several aircraft since 1998 and have demonstrated excellent reliability in a harsh environment.
(C) 2005 Stock Flight Systems page 7 of 26 CANaerospace at a glance
¥ Democratic network: No master/slave relationships for normal operation
¥ Self-identifying message format: Information about data type and transmitting station
¥ Message numbering: Support for coherent data processing in redundant systems
¥ Message status code: Continous integrity monitoring support
¥ Emergency event signalling mechanism: Information about CBIT detected failures
¥ Node service mechanism: Addressing of specific stations for integrity monitoring, data download, time synchronisation, .....
¥ Identifier assignment: Proposed default identifier distribution (similar to ARINC429)
¥ Ease of implementation: Reduction of work required for certification
¥ Openness to extensions: Minimum of fixed definitions to provide flexibility
¥ Free availability: No cost for use, free source code, free specification and tutorials
(C) 2005 Stock Flight Systems page 8 of 26 CANaerospace basic message format
¥ Node-ID (Byte 0): Some system architectures employ backup units which become active if the main unit fails. The Node-ID allows to immediately identify this situation and react accordingly (i.e. mode change within redundancy management). ¥ Data Type (Byte 1): CANaerospace supports multiple data types for every message. Backup units (or units from different vendors) may use different data types while performing identical functions. Specifying the data type with each message allows automatic system configuration, even during runtime. ¥ Service Code (Byte 2): For Normal Operation Data, this byte should continously reflect the status of the data (or the transmitting unit) to support data integrity monitoring within receiving units. With this information, the validity of data is known at any given time. ¥ Message Code (Byte 3): Message numbering allows to detect if messages are missing and if the transmitting unit is operating properly. Also, it can be used to compare the "age" of messages from redundant sources. CANaerospace message header 11/29-bit CAN identifier Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7
Message Identification Message Data (message type specific) Message Code (data type UCHAR) Service Code (data type XCHAR) Data Type (data type UCHAR) Node-ID (data type UCHAR)
(C) 2005 Stock Flight Systems page 9 of 26 CANaerospace identifier range definitions
Emergency Event Data 0 - 127 128 data objects
High Priority Node Service Data 128 - 199 72 data objects (36 com. channels)
High Priority User-Defined Data 200 - 299 100 data objects
Normal Operation Data 300 - 1799 1500 data objects
Low Priority User-Defined Data 1800 - 1899 100 data objects
Debug Service Data 1900 - 1999 100 data objects
Low Priority Node Service Data 2000 - 2031 32 data objects (16 com. channels)
(C) 2005 Stock Flight Systems page 10 of 26 CANaerospace default identifier distribution (examples)
System CAN identifier Data type Units Notes parameter name
317 Calibrated airspeed FLOAT m/s ($13D) SHORT2 321 Heading angle FLOAT deg +/-180o ($141) SHORT2 401 Roll control position FLOAT % right: + ($191) SHORT2 left: - 500-503 Engine #n N1 FLOAT 1/min N1 for jet , RPM for pi- ($1F4-$1F7) (1 < n <= 4) ECS channel A SHORT2 ston engines 1008 Active nav system track error FLOAT deg service code field con- ($3F0) angle (TKE) SHORT2 tains waypoint # 1070 Radio height FLOAT m ($42E) SHORT2 1205 Lateral center of gravity FLOAT % MAC ($4B5) SHORT2
(C) 2005 Stock Flight Systems page 11 of 26 CANaerospace proposal for the physical interface
CAN
DC DC DC DC
Power +28VDC 1 6 RS-232 RxD (maintenance/service) CAN Low 2 7 CAN High unused 3 8 unused RS-232 TxD (maintenance/service) 4 9 RS-232 Gnd (maintenance/service) Power Gnd 5
MIL-24308/8 CANaerospace connector
(C) 2005 Stock Flight Systems page 12 of 26 CANaerospace proposal for the physical interface (contd.)
+5V +5V CAN Vcc
100nF NM 05-05 100nF
0V 0V CAN GND
1 8 10k VDD1 VDD2
CAN Tx 2 6 VI VO 3
HCPL-0710
4 5 1 7 GND1 GND2 TxD CAN High TJA1040 CAN
8 1 4 6 VDD2 VDD1 RxD CAN Low REF CAN Rx 6 2 GND RS Vcc VO VI 2 8 5
HCPL-0710
5 4 GND2 GND1
(C) 2005 Stock Flight Systems page 13 of 26 CANaerospace proposal for MIL-C-26482 and MIL- C-38999 connectors
A F B
C E D Internal Proposed pinout: External
MS3476L1006SN Pin 1/B +28VDC Pin 2/E CAN Low Pin 3/F unused 1 shielded twisted 2 11 10 Pin 4 RS-232 TxD pair or quadruple 3 Pin 5/A DC Gnd (CAN or CAN/power) 12 13 9 4 Pin 6 RS-232 RxD 8 5 Pin 7/D CAN High 7 6 Pin 8/C unused Pin 9 RS-232 Gnd D38999/26FB35SN Pin 10 +28VDC Pin 11 DC Gnd shielded twisted Pin 12 CAN Low pair or quadruple 1 (CAN or CAN/power) 5 Pin 13 CAN High 6 2 4
3
D38999/26FA35SN
(C) 2005 Stock Flight Systems page 14 of 26 Example for a suitable CANaerospace cable Requirements: 120Ω impedance, low capacitance
(C) 2005 Stock Flight Systems page 15 of 26 CANaerospace projects (1)
Eurocopter All-Weather Rescue Helicopter (AWRH)
¥ CANaerospace as interface between navigation system, flight state sensors and pilot’s control MFDs units CDU ¥ Flight tests proved reliability and performance of CANaerospace data AWRH special equipment rack communication NECS/Avionics NECSlite ADC/AHRS
Avionic control units/ CANaerospace bus Joystick
NECSlite
MFDs
CDU
(C) 2005 Stock Flight Systems page 16 of 26 CANaerospace projects (2)
Stock Flight Systems Data Recording System (FDR1-CAN) ¥ Modular, CANaerospace- based flight data recording system ¥ Installed in Pitts S-2B as continuous testbed 1024x768 colour TFT with integrated Linux GPS Antenna ¥ Used in Eurocopter helicopters computer system SFIM APIRS F201 CANaerospace Joystick Control Unit Attitude/Heading and various research aircraft Reference System
OAT probe ARINC 429
Pitot/Static Inputs
1 1 2 1110 2 1110 3 9 3 9 41213 41213 5 8 5 8 6 7 6 7 CANaerospace
Aileron
Elevator Optional Linux laptop computer for test, Rudder maintenance and software development with VISTA2D visualization tool Power Lever PowerNECS Avionics Interface Unit Control Position Transducers
(C) 2005 Stock Flight Systems page 17 of 26 CANaerospace projects (3)
Stratospheric Observatory For Infrared Astronomy (SOFIA)
¥ NASA/DLR program for high altitude infrared astronomy CANaerospace network ¥ CANaerospace used for communication between star tracking system and realtime control computers for telescope control
¥ CANaerospace network length 40m
¥ System integration in 2002, first flight planned for 2004
¥ Website: http://sofia.arc.nasa.gov
(C) 2005 Stock Flight Systems page 18 of 26 CANaerospace projects (4)
¥ The “System of Aviation Modules (SAM)” UNIS contact: UNIS spol. s.r.o. has successfully passed CAA (Cz) Jundrovska 33 certification for the Ae270 business/small 62400 Brno Czech Republic transport aircraft developed by Aero phone: +42-0541515541 Vodochody a.s. (www.aero.cz) and AIDC fax: +42-0541210361 Ltd. of Taiwan. email: [email protected] ¥ SAM comprises of seven intelligent units which communicate under each other using CANaerospace. All SAM units are qualified according to RTCA DO-160D/DO-178B and meet the HIRF (High Intensity Radiated Fields) requirements. The certification is based on FAR part 23. ¥ The SAM functions include electric power supply monitoring, fuel distribution and supply control, hydraulic system control, propeller heating control, airframe load monitoring, deicing control, etc.
(C) 2005 Stock Flight Systems page 19 of 26 CANaerospace projects (5)
Bombardier-Rotax V220/300T aircraft engines
¥ Fuel-injected, watercooled, 120- degree V-6 engine line with dual redundant electronic engine control unit and CANaerospace data bus ¥ CANaerospace-interfaced Engine Monitoring Unit providing the pilot with all engine data already installed in several aircraft ¥ FAA/JAA certification expected 2003, first deliveries in 2004 ¥ Website: www.VaircraftEngines.com
(C) 2005 Stock Flight Systems page 20 of 26 CANaerospace projects (6)
NASA Small Aircraft Transportation System (SATS) program
¥ SATS is a partnership among various organizations including NASA, the Federal Aviation Administration (FAA), US aviation industry, state and local aviation officials, and universities. ¥ The target is to develop all weather operations within the entire US airspace for general aviation. ¥ CANaerospace/AGATE databus serves as the central avionics backbone network in the research aircraft used for the SATS program flight tests.
(C) 2005 Stock Flight Systems page 21 of 26 CANaerospace projects (7)
Various Flight Simulators BO105 728 JET ¥ Dornier-Fairchild 728JET engineering simulator ¥ Eurocopter TIGER simulators ¥ Eurocopter BO105 procedure trainer ¥ Eurofighter Typhoon simulator ¥ EADS Mako demonstrator ¥ NH90 engineering simulator Eurofighter TIGER
NH90
Mako
(C) 2005 Stock Flight Systems page 22 of 26 CANaerospace products and services (1) Stock Flight Systems
Products/Services:
¥ CANaerospace specification ¥ Flight data recordering systems ¥ Embedded realtime control computers ¥ CANaerospace network installations ¥ CAN interface boards and driver software ¥ Consulting services
Stock Flight Systems Schützenweg 8a D-82335 Berg/Farchach Germany Phone: +49-8151-9607-0 Fax: +49-8151-9607-30 Email: michael@stockflightsystems.com www.stockflightsystems.com
(C) 2005 Stock Flight Systems page 23 of 26 CANaerospace products and services (2) Reiser Systemtechnik
Products/Services:
¥ Night vision compatible simulation cockpit instrumentation ¥ Design and manufacturing of entire simulation cockpits including ejection seat mock-ups ¥ Design and manufacturing of test facilities
Reiser Systemtechnik GmbH Oberer Lüßbach 31 D-82335 Berg/Höhenrain Germany Phone: +49-8171-4373-0 Fax: +49-8171-4373-30 Email: [email protected] www.reiser-systemtechnik.de
(C) 2005 Stock Flight Systems page 24 of 26 CANaerospace products and services (3) Wetzel Technology
Products/Services:
¥ CANaerospace tools ¥ Data visualization ¥ Digital map applications ¥ Operator stations ¥ Instrument simulation
Wetzel Technology GmbH Hermann-Oberth-Stra§e 11 D-85640 Putzbrunn Germany Phone: +49-89-460892-62 Fax: +49-89-460892-63 Email: [email protected] www.wetzel-technology.de
(C) 2005 Stock Flight Systems page 25 of 26 US Representative for Stock Flight Systems, Reiser Systemtechnik and Wetzel Technology
ICS, Inc. Mr. Kevin Jacobson 1102 West Aster Drive Phoenix, AZ 85029-2808 phone: +01-602-564-0851 fax: +01-602-588-9440 e-mail [email protected] website: www.ICSAero.com ¥ Innovative Control Systems, Inc (ICS) was established in 1991 as a provider of aerospace engineering services and equipment to High Technology Aerospace Companies. ¥ Their customer base includes companies such as Honeywell, Raytheon, Dornier Luftfahrt, Hamilton Sundstrand, B.F. Goodrich, Aircraft Braking Systems, Vibrometer, Smiths Industries, and many other aircraft manufacturers and equipment suppliers.
(C) 2005 Stock Flight Systems page 26 of 26