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This paper discusses the profile framework of CANopen protocol for a hybrid electric vehicle (HEV). Based on the analysis of the CANopen protocol and the HEV system structure, a preliminary version of CANopen profiles for the HEV is firstly drafted out. Then the object dictionary for each HEV module and communication mechanism of the vehicle network is described in detail. Finally the CANopen profile's fault diagnostic modes of HEV based on OBD-II and SAE J1939 are set up. Finally the attempt to implement the profile in slave node of electromotor in HEV based on the DSP of TMS320F2812.

This project demonstrates the usefulness of a proposed plug and play communications standard (CANopen) for the medical device industry. A use case involving a hospital bed and an invasive blood pressure monitor (IBPM) was used for demonstration. Currently, IBPMs only measure a patient's blood pressure accurately if the patient's heart is at the same height as the monitor's air-fluid interface. Any change in height between the patient's heart and the monitor's transducer (air-fluid interface) will yield inaccurate blood pressure measurements. The solution corrects these inaccuracies by allowing devices to communicate relevant data to each other. This solution has been successfully developed in the CANopen application layer and a working prototype of the desired use case exists. This is the first use case of many that the investigators hope to implement, with the main goal of the project to inspire the need for a standardized communications network. The completion of this use case demonstrates the benefits of communication amongst different medical devices, and the team hopes that such a network will be employed in hospitals in the near future.

Fieldbus systems have become an important factor in communication between industrial control devices. In this paper, the authors report how, since originating as an Esprit project, CANopen has evolved to become an increasingly popular real-time networking system.

This paper describes the design (hardware and software) and implementation of a modular communication system based on CAN network. The motivation of the work is related to the real-time distributed control systems field. The goal is to own the complete control of the communication stack when building embedded distributed prototypes. This would allow managing those communication issues that affect real time performance (i.e. computation of worst case execution times and priority assignment to tasks and messages). This CAN implementation (rtfCANopen) is modular, inexpensive, auto-downloadable and self-configurable. A case study, consisting in an autonomous mobile robot that uses rtfCANopen, is described. This prototype is designed and analysed using the Real-Time Framework developed by authors. This framework consists of a set of tools for developing real-time distributed systems and it covers all the phases: specification, analysis, simulation and code generation of distributed applications.

As a kind of CAN-based application layers, the CANopen protocol has been widely adopted for distributed control system. While the introduction of network gives the system some advantages, the jitter problem of system variables is induced and degrades the performance of systems. The optimal algorithm can be used to reduce the jitter of system variables. According to the CANopen transmission features, the real-time communication problems in CANopen are analyzed. The genetic algorithm is used to optimize the synchronous message scheduling. A multiple sensor network is simulated using the CANoe software. The result shows that the jitter problem in the network can be effectively reduced and the performance of the system can be improved.

The CANopen protocol based on embedded control applications has been widely applied into networked control systems. The jitter problem of system variables induced by the network transmission becomes a primary aspect of the current research on networked control systems. To reduce the jitter of system variables, the genetic algorithm is introduced to optimize the synchronous message scheduling based on the CANopen transmission feature. The message scheduling is implemented using the application hardware. The response time of messages can be measured and tested using the CANalyzer. Based on the practical application, the optimal scheduling algorithm is validated. The result shows that the jitter problem in this network can be effectively reduced.

The paper deals with the several topics related to the development and production of the ultra low-floor tramcar, type TMK2200, for the city of Zagreb. During the development many electronic control units have been specified, designed and integrated into the vehicle. The communication between these control units is mostly based on CANopen. The reasons for selecting CANbus and CAN open application layer are discussed. Furthermore, several proprietary hardware and software solution have been developed for this project. These solution, among other, include redundant main vehicle control unit. The concept of this unit is presented, along with some details that increase vehicle reliability and availability. Finally, some experience facts and possible future improvements are also pointed out.

For most of history, safety-related systems used only mechanical backups. These systems are specialized. In only a few application fields or pilot projects the mechanical systems are replaced by electronic solutions. The time has come when more engineers want to design using electronic systems instead of mechanical. For this to be possible a Solution must exist. The communication network must support this. In its current usage, CAN, does not have all the requirements necessary for use in safety-related applications. Even after adding CANopen as the higher-layer protocol specific needs were not met. After exploration of these deficiencies, the CANopen Framework for Safety-related applications was created. This framework allows the use of safety-related and non-relevant communication on the same network. The basic idea is to transmit each safety-related message twice using different message identifier. The data is bit-wise inverted as well with a time-out attributes assigned. CANopen can now be used for safety-related applications. If CANopen is the Solution, then a one microprocessor can be the Single Solution for the application within a device.

The system is a new online monitor system. It is consisted of a master station, which is a computer with intelligent CANBUS interface unit, and a slave station, which is a monitor module for battery parameter measure. At first, this paper introduced the hardware circuit framework of the monitor module, and then, focused on the software design, including the automatic monitoring of CANBUS bit-rate, the initialization of CAN controller, the transmission, abort transmission and reception of messages. By comparing DeviceNet and CANopen, it explains the reason that CANopen is selected the application layer protocol.

The paper deals with the scheduling of information flow in a CAN ISO IS-11898 communication system. It mainly features a bus access arbitration protocol based on a priority assigned to each message to be transmitted; if two or more messages are transmitted at the same time by different communication nodes, only the message with the highest priority continues to be transmitted, the other being stopped. In real-time applications, messages contain information which must be transmitted within strict time constraints; according to the CAN ISO IS-11898 bus arbitration protocol, respect of real-time constraints of time critical information depends on the priority assigned to the message conveying it. The aim of the paper is to propose a procedure for dynamic assignment of priorities to messages to be transmitted, in such a way the real-time requirements of the information conveyed are fulfillled. Although many other approaches can be found in literature, the proposal is original as It is based on standard full CAN communication stacks.

CANopen is a fieldbus protocol based on the controller area network (CAN). This paper analyzes guaranteed cost control of a class of networked control systems accordant with the CANopen protocol. The timing of this system is analyzed. In terms of its characteristic, delay produced by the network is discussed. This system can be modeled as an uncertain discrete-time system. In terms of the network-induced delay and the system model, the delayed state feedback controller is designed. Guaranteed cost control of this system is also discussed. The condition to meet a certain cost function is proposed.

This paper describes the drive control structure of the Railcab system realized at a test track at the University of Paderborn based on a distributed data processing system. The drive of this railway system, a doubly-fed linear motor, consists of two active parts distributed on the vehicles and along the track, which both have to be powered. Safe operation of the Railcabs is guaranteed by a mechanism synchronizing the current controllers via different communication channels (CANopen and radio). This measure makes possible to control the phase shift between the magnetic fields of primary and secondary which is a must for drive control. Finally measurement results are presented to prove the functionality of the described synchronization mechanism.

This paper describes the proposal of a CANOpen profile for use in electric energy transmission and distribution plants, more specifically for lap position control and supervision in multi-tap autotransformers using master-slave configuration. The proposed profile allows the interconnection of electric plant sub-station's equipments through a CANOpen network making usage of low cost microcontrolled boards, programmed in Java language. The implemented network adopts the "following master" algorithm in a producer/consumer topology, adding flexibility and temporal determinism to the plant. The realtime behavior of the implemented profile is evaluated using the BR-Tool multiprotocol analyzer developed by the authors.

The Controller Area Network (CAN) has seen enormous success in automotive body and powertrain control systems, and in industrial automation systems using higher layer protocols such as DeviceNet and CANopen. Now, the CAN standard ISO11898 are being extended to Time Triggered CAN (TTCAN) to address the safety critical needs of first generation drive-by-wire systems. However, their successful development depends upon the availability of silicon and software support, and appropriate development & analysis tools. This paper outlines the current status of TTCAN technology and describes the implementation of Level 1 TTCAN on the Atmel 89c51cc01/cc02/cc03/cc04 microcontrollers. The descriptions contained show how to implement for different bus speeds, along with suggestion for a user to tailor the drivers for their own application. Level 2 TTCAN is also described for comparison purposes. Whilst the TTCAN implementation described in this paper is limited to the maximum CAN bit rate of 1Mbit/s, TTCAN can be used to effectively double the bandwidth of a CAN system to the region of 60 to 70% bus loading at 500 Kbit/s and 1Mbit/s. This is approximately twice that of traditional automotive CAN systems. For example, a typical automotive power train control system based on CAN typically runs at maximum of about 35% loading at 500 KBaud to avoid data bus latencies.

The paper deals with the communication busses of the ultra low-floor tramcar TMK2200. The development process from the appropriate bus selection till implementation, testing and production have been described. The reason for selecting CAN bus and CANopen communication protocol, along with the basic information on CAN and CANopen have been presented. Some experience facts and possible future improvements have also been pointed out.

At present, a number of platforms are becoming available for the implementation of intelligent field devices, which are based on low-cost microcontrollers and open-source real-time operating systems. To take full benefit from these platforms and to ease the task of developing and porting the application software, a standard interface has to be provided to cope with communication facilities. In this paper an application programming interface for CANopen is introduced that relies on the well-known socket paradigm. Despite its inherent simplicity, it is very flexible and offers the programmer all the functionalities foreseen by the CANopen specification.

The Office of Research and Development of the Federal Railroad Administration (FRA) is sponsoring a revenue service demonstration of Advanced Train Systems to demonstrate new technologies for improving safety and efficiency in freight train operations. The project, which commenced in 1999, is part of the Rolling Stock Program Element in FRA's Five-Year Strategic Plan for Railroad Research, Development and Demonstrations. The demonstration system, referred to as the on-board monitoring and control system (OBMCS), features an integrated package of sensors and actuators for monitoring and controlling mechanical components on freight trains. The OBMCS includes sensors to monitor bearings, wheels, brakes and trucks and actuators (referred to as advanced components) for remotely controlling hand brakes, angle cocks, cut levers and a cushion unit lockout system to eliminate slack. The demonstration, scheduled to commence in 2005, will feature a locomotive equipped with an EMD FIRE computer system and five freight cars equipped with the OBMCS and a New York Air Brake ECP brake system. The cars will also be equipped with Sharma & Associates tri-couplers, which automatically couple the cars, the pneumatic line and the ECP brake power cable. An open system architecture based on controller area network (CAN) technology provides the framework for integration and control of the advanced components. The CAN bus network is also employed to monitor bearing temperatures and the status of brake piston travel sensors. A communication protocol based on a subset of CANopen Draft Standard DS401 V2.1 [CiADS401] has been developed to facilitate integration of sensors and actuators into the OBMCS. Science Applications International Corporation and Wilcoxon Research developed the sensor and supervision platform to integrate the advanced components. The OBMCS is powered by a battery, which is recharged by a generator bearing developed by the Timken Company. Intra-train communication and control from the locomotive is over an 802.11b wireless LAN. The FIRE computer in the locomotive receives status information from the systems on each car and transmits commands to the cars to operate the advanced components. Hot bearing, derailed wheel and truck hunting events are immediately relayed to the locomotive engineer. The OBMCS is also equipped with a IXRTT cellular radio to transmit results to a central database and website. A GPS receiver provides time and location information necessary to track a car. On board sensing of mechanical defects enables car owners to track defects and pro actively schedule maintenance at an economical time and location.

Every now and then a simple idea can be elected as the best idea. Many times we look to make things more complex instead of looking at existing solutions to see if they can be modified to work. Historically, safety-related systems used only mechanical backups which were specialized. In only a few application fields or pilot projects the mechanical systems are replaced by electronic solutions. But having separate network solutions does not really simplify the solution. In its current usage, CAN, does not have all the requirements necessary for use in safety-related applications. Even after adding CANopen as the higher-layer protocol specific needs were not met. After exploration of these deficiencies, the CANopen framework for safety-related applications was created. This framework allows the use of safety-related and non-relevant communication on the same network. The basic idea is to transmit each safety-related message twice using different message identifier. The data is bit-wise inverted as well with a time-out attributes assigned. CANopen can now be used for safety-related applications. If CANopen is the solution, then a one microprocessor can be the single solution for the application within a device.

To construct a vehicle collision avoidance system, a laser radar and three ultrasonic sensors are integrated with the CAN bus to build the in-car network architecture to prevent the car on all directions. There are two sub-systems developed for this collision avoidance system: (a) the front-end sub-system and (b) the side and rear-end sub-system. The front-end collision warning sub-system is constructed for high-speed driving conditions by measuring the distance in the front with a laser radar. Moreover, the relative speed between two cars can be properly estimated by applying the current Kalman filter. Then, a D/V curve is further obtained to generate collision warning with a desirable precaution time to prevent the front-end collision actively. For the collision avoidance on the side and the rear-end, the approaching speed from other cars in general is slow and available ultrasonic sensors with limited range and resolution are adopted. An intelligent approach is proposed to process the rough distance readout to render warning signals with suitable timing for the approaching car drivers to prevent the collision passively. A high-level network protocol CANopen is applied to integrate all ultrasonic sensors as the in-car network communication.

This paper presents BR-Tool, a multi-protocol bus monitoring and temporal validation software developed to provide temporal validation of fieldbus-based automation applications. BR-Tool monitors communication on industrial networks during real operation and compares acquired data with temporal requirements previously specified. Two industrial case studies are presented in this paper: the first one is a PROFIBUS-DP based manufacturing system, and the second one deals with a energy control system application based on CANOpen protocol.

This paper describes both the electronics design (ED) and the acceptance control system (ACS) of the Commissioning Instrument (CI) for the Gran Telescopio Canarias (GTC). The CI mainly comprises ten mechanisms accurately positioned by control algorithms, which in turn are programmed according to the CI operation modes. The control system is based on a CANopen protocol and is completely compatible with the GTC control system. CANopen is a serial communication protocol based on CAN bus. The CANopen features allow for the control system high reliability. A Reliability, Availability, Maintainability, and Safety (RAMS) analysis was carried out to guarantee the CI opto-mechanics and electronics performance.

A highly distributed system for laboratory test and experiment monitoring and control is presented. The SCADA (Supervisory Control And Data Acquisition) approach, as typically found in the industrial environment, was followed to base this design, leading to a rigidly structured architecture which proved to be highly manageable and robust. Ultimately, a powerful laboratory aid tool was the result of a virtuous combination of a sound modularity concept with a communication mechanism based on the CANopen high-level protocol serving a virtual instrumentation strategy.

The author deals with the problem of information flow management in a CANOpen network. CAN ISO IS-11898 physical medium access mechanism. adopted in CANOpen, features an arbitration protocol based on an identifier assigned to each message to be transmitted. The lack of a centralised scheduling for the identifier assignments in CANOpen does not allow achieving any guarantee to meet the deadlines of time-critical messages. The aim of the paper is to propose a protocol for dynamic and centralised assignment of identifiers to each message to be transmitted, in such a way that its transmission requirements are fulfilled. The main features of the protocol proposed are the operational flexibility it offers and full compatibility with the CANOpen standard.

The correct operation of the CANopen protocol relies on the assumption that each node in the network be identified uniquely. To this extent, the CANopen specifications provide a means to remotely configure the addresses of the slave devices attached to the CAN bus. This technique, however, requires that each device has to be connected separately to a configuration tool. CANopen, in fact, does not have a mechanism to identify, in an efficient and reliable way, the nodes that do not have an associated address when they have already been connected to the network. In this paper, we present a new automatic node discovery protocol, which is able to eliminate such drawbacks. Our technique can be used to identify the nonconfigured nodes directly in the final system and is conceived as an extension of the basic layer setting services of CANopen, so as to provide a very good degree of compatibility with the existing devices.

In this paper a new technique is introduced that enables the communication efficiency of CANopen networks to be increased above its current limit. In particular, significant improvements can be achieved in all those cases where the application master needs to poll whole groups of input devices or process data have to be sampled at different rates. The new mechanism does not require any modification to the hardware of CAN controllers, but only slight changes to the CANopen protocol stack. Thus, it can be implemented easily and inexpensively by simply upgrading the firmware of the existing devices.

The paper presents two solutions aimed at making the CAN networks deterministic and composable. The two solutions run on the application layer and exploit the services offered by either CANopen or the native CAN protocol. In the first solution, named Multimaster, each node operates as a master and the transmission cycle is initiated by a synchronization message. In the second solution, named SynCAN, each node transmits only in a fixed slot of time and in a sequence established a priori. The efficiency of the two solutions is analyzed and experimental data on the first solution are given.

Computers are increasingly used for problems that require software solutions that must satisfy real-time constraints and are distributed in nature. The communication standards are developed and administrated by user organizations in which universities play an important role. In this paper, most of the existing user organizations working in the field are listed and our experience with industry is shown. Advantages of fieldbus systems and the role of our laboratory in co-operation with industry are explained. The controller area network (CAN) is a well-known bus technology in industrial communication systems. This paper shows an implementation of the CANopen protocol used by one of our industrial partners in trains and mining machines.

CANopen is a field level communication protocol for industrial automation distributed applications. CANopen offers a powerful set of higher level application layer services which implement an object-oriented distributed environment for simplified system integration. Often, sensors and actuators have to be placed at geographically remote locations, at considerable distances from the processor(s) running a control application. When this is the case, a possible solution is to use an autonomous I/O module, located close to the sensors and actuators, that provides the application with an interface to these devices. The application must be distributed between the remote I/O module and the local processor(s) using a communication network to allow the different parts to cooperate. This work is centred on the development of an I/O module based on the SAB-C167CR-LM chip from SIEMENS. The I/O module makes sensors and actuators accessible via the CAN bus, using the CANopen protocol. The objective is to show that CANopen can be implemented over new hardware platforms, in minimum time, with satisfactory results. It is shown that CANopen provides a systems-integrator-friendly object-oriented environment and that for this reason, the CANopen Communication Profile greatly simplifies the implementation of distributed applications in CAN based systems. Furthermore, CANopen also provides flexible real-time data transfer mechanisms that are able to meet time-critical constraints and, therefore, make CANopen a good solution for distributed control environments.

The Controller Area Network or CAN provides the user with many powerful features including multi-master functionality and the ability to broadcast/multicast telegrams. The low cost of CAN components, high data reliability and short reaction times together with its huge user base will ensure future of CAN is safe for an extremely long time to come. However, to ensure inter-operability between CAN components, several higher layer protocols have been developed to allow devices to communicate in a standardised manner. CANopen is one of these protocols and has already seen wide adoption within industry and other sectors such as building automation and public transport. This paper discusses various aspects of CANopen communication and gives a general overview of some of its powerful features.

The paper describes an European field bus communication standard developed during ESPRIT IV project 7302 and subsequently has become known as CANopen. CANopen Configure Device and Test (CDT) software has been developed by Newcastle University (UK) to facilitate the configuring and testing of CANopen devices. The CDT is further enhanced to perform conformance testing of I/O devices. To operate the software requires a PC running Windows and a CAN card supporting CANopen. It allows the use of any CANopen compliant object dictionaries to communicate with the device. Any object can be read or written, for both service data and process data communications. Synchronisation messages can be generated automatically, with real time display and control of synchronous data. Full CANopen network management services and life guarding are implemented and there is an object dictionary editing facility.

An embedded network linked by CAN (controller area network) controllers and the CEINFO software tool are combined. It solves the university's teaching about the industrial automation. To generate codes for the distributed control units (DCU), to develop an operating system for the intelligent gateway handling them, to control the monitored process. The ALDS software, version 1.0 guarantees the cooperative work in real time over the CAN network. The embedded network consists of "Evaluation CAN-ISA gateway card based in the MCS51" and several modules developed with the PIC16F877 Process Microcontroller and the MCP2510 CAN controller. The paper explains a simplified variant to built the communication objects (derived of the CANopen model) PDO, SDO and NMT using a little bit of hardware resources.

This paper introduces CANINSIGHT which was developed to create a device and platform independent fieldbus management system for highly distributed enterprises. System data are represented as XML documents which are instances of the CANopen Markup Language (CoML). CoML is an XML application for Controller Area Network (CAN) device profiles, setup information, and process data. The system uses a CoML-based Java client/server architecture to access arbitrary CANopen fieldbus devices via the Internet. The CANINSIGHT client, realized as a Java applet, provides convenient, interactive access to CANopen automation systems at remote locations. The CoML documents which are used for the client/server communication can also be exported to remote database systems and form a central process information repository for an entire manufacturing enterprise. It is possible to use standard database clients to request specific CoML information which can be processed either by dedicated CoML tools or a wide variety of general purpose XML tools.

Object oriented problem analysis and software design is becoming more common in the field of industrial control. We present the Java CAN API which provides a convenient, object oriented programming framework for rapid CAN field bus tool development. It provides a hierarchy of classes and interfaces to access arbitrary CAN/CANopen devices via the Java Native Interface. In order to access Windows-based CAN drivers a native dynamic link library has been developed featuring high performance message filtering and asynchronous message notification. The created Java class hierarchy encapsulates the CANopen layer 7 communication objects as well as generic CAN layer 2 messages. Further classes provide access to the CANopen network management services. The paper also briefly presents some practical uses of the Java CAN APl for teleservice, distance education and CAN system management.

Networked control systems (NCS) are focused on a real-time control over the several bus types. Real-time extensions for the operating systems, which are popular in industrial applications, were developed to ensure precise timing. Aim of this paper is to present a communication platform for real-time process control. Platform communicates with CNC laboratory model of industrial plasma cutter via CAN bus. Real-time extension RTAI with communication driver modification was used to develop such platform. Console application was programmed to interact with the laboratory model in manual operation mode.

This paper presents a modeling for the safe design of intelligent instruments distributed on a CANopen fieldbus. This paper briefly recalls the service-based USOM/INOM modelling technique, then shows how this technique can be apply to a safe design of CANopen distributed instruments. An example of design of an instrument which is compatible with the CiA DSP-401 standardized profile of I/O modules, is used to illustrate these concepts.

Information technology and communication technology offer increasingly improved possibilities for automation and robotisation in mobile construction machines. Apart from the electronic systems the intelligent connection of subsystems by a network plays a crucial role. The preconditions for the connection within mobile construction machines were created with the research project "Standardisation of Open Communication in Mobile Construction Machines". For a full automation in mobile construction machines a management system should be used, in order to connect the subsystems in the future.

The advantages, which decentralized automation will make available to the machine and plant designer, are still to be seen. In discussion is a solution that can be realized now because the necessary components and technologies are all readily available, such as: Ethernet-TCP/IP, CANopen, industrial-compatible rail mounted PCs, OPC and IEC 1131-3.

The trend towards decentralized concepts in fluidic systems requires effective communication structures between the networked components. Fieldbusses are designed to meet these requirements. When using similar devices from different vendors, a harmonization concerning communication objects and devices’ behavior has to be reached in order to minimize efforts in design and configuration of the whole system. Thus, a bus-system independent device profile for fluidic components has been defined. This profile has been mapped to CANopen. The article describes the profile and the CANopen mapping and the description technique used.

Conformance tests are used to guarantee that different products can work together. For that reason there was founded a group which defines a test procedure for CANopen devices based on the CANopen Communication Profile DS301 V3.0. This test procedure will guarantee that CANopen devices can communicate on the bus, the default values are set correctly to the standard and the network state machine is correctly implemented.

Embedded networks are used for machine or system internal communication between module and sub-systems. One of the most important embedded networks is Controller Area Network (CAN). In the early days of CAN, the embedded system designers have developed their own higher-layer protocols. Today, most of the system integrators like to use standardized application layers and communication profiles to reduce design efforts. CANopen is a family of specifications including communication profiles, frameworks, and device profiles for embedded networks based on CAN.

CANopen based on the popular controller area network (CAN) represents an ideal networking system for distributed control systems and overcomes the limitations inherent in conventional master/slave and peer-to-peer networks. The paper discusses the benefits of using CANopen and describes its implementation on a distributed motion control system.

The success of the fieldbus technology began with the reduction of the wiring effort in machines and plants. For this first step the traditional control architecture was extended to a remote-I/O control architecture. The development has gone further and nowadays the control architecture with distributed intelligence is the state of the art.

CANopen networks and devices can be configured in a variety of different operating modes. More importantly, CANopen services may be distributed across different devices within the network. This paper briefly discusses some issues in construction of a CANopen network. (3 pages)