Wireless communications applications in agricultural machinery
and 
technical briefing
* Applications photos and examples presented by
manufacturers on international exhibitions in 2005/2006
Examples of wireless solutions for a wide variety of uses...
...some available for a long time
The use of wireless technology in machinery is not a recent phenomenon. The forestry equipment sector has used remote control systems for forestry winches for several years, such as the one produced by the German equipment manufacturer TELENOT-B&B Electronic and sold to forestry equipment firms such as Tajfun (Slovenia) or PM (Germany). The device uses the ISM 70 cm waveband (6 channels from 434.1 to 434.775 MHz – transmitting power 10 mW – usable without registration or fees) and allows an operator on foot to manage the direction of movement and rotational speed of a winch positioned in front of a skidding tractor. It works with all makes of winch as well as other systems, such as those for regulating engine fumes, emergency alert systems and warning devices. The device can be used to call the emergency services should the need arise. The most advanced operating mode, known as “passive alert”, can trigger an alert automatically if the operator is no longer able to do so (e.g. if there has been no movement for a predefined period of time). The remote control device for the F9 series is connected to the Comtac 1204 transmitter installed in the vehicle, which determines its exact position using a GPS system and transmits its coordinates with the emergency call over a GSM mobile network to an emergency call centre that operates 24/7.
Manufacturers of irrigation equipment were also pioneers in the use of wireless technologies for remote control of irrigation pivots and drums. One example is the OMEGA Online system used on equipment manufactured by LINDSAY Europe - PERROT, which includes the option of sending voice messages on the status of the drum by GSM, either at the request of the remote operator, or by the system itself if it picks up a fault, triggering a warning message. Stop and start commands for moving the pivot or the associated pumping system are also possible.
Medium-range solutions that do not require a licence are available in addition to GSM communications. FIELDSENSOR LINK, also distributed by LINDSAY, uses a digital transmission system (frequency 902-928 MHz, transmission speed 9600 bauds, power 100 mW) with a maximum range of 2.5 km. This system is used to transmit the measurements from a humidity sensor in the plot concerned to a remote data acquisition centre (up to 50 probes can be connected).
The remote mobile camera also helps the driver at various stages of the job, manoeuvring, coupling, decoupling, etc... when working with agricultural or site machinery that is very large and/or has areas that are partially hidden from the cab
... or only very recently
The Dutch company DIGI-STAR produces a wide range of weighing equipment for mixer-blender-feeders used to distribute animal feed (e.g. control devices for equipment manufactured by LUCAS-France). The scale indicator (e.g. type EZ 3500) placed in the cab of the tractor, linked wirelessly to the mixer-blender, is used to manage the different quantities of raw materials (silage, soya, etc.) needed to make the feed selected by the farmer. This information is not available, however, when the same person is controlling a mobile loader to fill the mixer. The new CAB Control unit, mounted in the loader’s cab, can communicate with the tractor’s scale indicator using radio signals (frequency 2.4 GHz, range 30 m) (cf. figure 1). All the scale indicator’s functions are then available from the loader.
fig. 1 – Link between scale indicator on feeder and control unit on charger (source Digi-Star)
REICHHARDT, a German electronic equipment manufacturer that supplies numerous manufacturers of beet harvesting machinery (ROPA, etc.) also has an AGID system for monitoring sugar beet production from the field to the sugar refinery. The system has been tested in the USA, and involves transport lorries being equipped with a transponder, which, when loading is complete, is sent various kinds of information (name of producer, name of plot, GPS position, time, tonnage, etc.) communicated by the beet harvester at the edge of the field. On arrival at the processing plant, the information is uploaded wirelessly to a server that manages batch traceability.
A wide range of products in the area of electronic customer service using GSM-GPRS technology
The electronic customer service sector is growing rapidly amongst manufacturers of agricultural equipment with a wide range of products (tractors, harvesting machinery, soil cultivation and/or fodder harvesting tools, etc.) such as JOHN DEERE, CNH, AGCO, CLAAS and others.
1- Example of JOHN DEERE services
The hardware part of the JDLink product line from JOHN DEERE consists of a control device linked to the CAN bus of the tractor, which has access to a set of parameters linked to the current status of the vehicle (geographical position, speed, how far it can travel before refuelling, etc.). These data are accessible throughout the day to the equipment fleet manager by logging on via the Internet with a confidential access code to a JOHN DEERE central server. Log-on and data repatriation between the server and the machine take less than 2 minutes over a GSM connection. Data from the machine are automatically sent to the server once a day to produce a daily log (number of hours of use, fuel consumption, etc.). In addition to productivity information, warning messages of different levels of seriousness relating to the operation of the machine (e.g. “red” alert - oil level problem - engine cut-out), can be generated by the machine and relayed by the server by e-mail or SMS message to the fleet manager but also, if they have granted them access, to their JOHN DEERE dealer to reduce the time taken to get help. Warning messages can also be sent if the machine leaves a pre-defined geographical area (specified in advance as a circle). The cost of the hardware (USA prices) is around $2,500 per machine, plus approximately $500 for an annual subscription to the website.
2- Example of electronic equipment manufacturers’ services
The Belgian company EIA Electronics develops and produces terminals and electronic cards for on-board applications (lorries, trains, site equipment, etc.). In the agricultural machinery sector, it works with the New Holland combine-harvester production unit of the CNH Group in Belgium. Its extensive product range includes the COM MODULE TRC 810 network card with an ISOBUS compatible CAN 2.0B interface (maximum speed 1Mbit/s), numerous digital or analogue input/output ports and remote communications options using GSM, GPRS or CDMA. The card also links to the Iridium and Orbcomm satellites.
This sophisticated network card is one of the components of the ARTIQ remote equipment management system produced by the Swedish company ARKUB. Mounted on a mobile machine, it is used to transfer data to a central server based on the same approach as the JDLink system described above, with data transferred to the server by GSM or GPRS and controlled access to the database for queries via the Internet (Cf. figure 3).
The range of functions is similar (information on usage rates, scheduled maintenance information (oil changes, etc.), warning messages, geopositioning for general supervision and as a theft alert, etc.).
fig. 3 – Overview of the ARTIQ system (source ARKUB documentation)
The German equipment manufacturer STW, which specialises in sensors and measurement systems for industry, also produces a range of control cards for on-board applications on mobile machinery (e.g. cooperation on agricultural equipment with the manufacturer FENDT – AGCO Group). The ESX-C2C module is an intelligent network card based on a 16-bit microcontroller with analogue (maximum 4) or count inputs, PWM outputs (maximum 2), RS232 interfaces and an ISOBUS compatible 15 CAN 2.0B (maximum speed 1 Mbit/s) interface. Remote communications are possible over a GSM/GPRS dual or tri-band connection. As figure 4 shows, the card plays a central role in building a communications architecture internal or external to the vehicle.
fig. 4 – Proposed architecture (source STW documentation)
STW gives developers working on electronic customer service and proprietary fleet management applications access to a software suite called ToolESX-KEFEX. These tools facilitate communications via GSM/GPRS between the server and the machinery, graphic representation of information (using a GIS), configuration of alert levels, etc.
The German company RM MICHAELIDES, which supplies electronic cards and software, also produces a comprehensive range of CAN/GSM and CAN/GPRS interface cards. The standard protocol is CANopen, however it has also developed products for some of its customers using the ISOBUS protocol.
RM also used the show to launch its Internet portal “ProEmion”, which consists of a central server for tracking an unlimited number of vehicles and has the potential to be developed further through partnership agreements with manufacturers of agricultural equipment, site machinery, etc.
Use of Bluetooth technologies
1- Mainly reserved for data collection
At SIMA 2005, FENDT marketed the MODASYS system linked to the tractor’s CAN bus to record various operating parameters as the vehicle worked. Developed by the German company RTS Riegger, the system has a Bluetooth connection to transfer data from the on-board calculator to a PDA (such as a Pocket PC, Palm OS, etc.) in one of its communications modes, the second being via a GSM link (on this point, once the initial investment has been made (€1,630), MODASYS users do not have to pay a subscription but only their standard GSM connection costs). The solution was adopted by various German agricultural equipment manufacturers which are still working in partnership with RTS. The diagram in figure 5 shows the system produced by KRONE20, which specialises in fodder harvesting machinery (chopper-blowers, self-propelled mowing machines, etc.).
fig. 5 – Data collection system on KRONE harvesting machinery (source KRONE documentation)
AMAZONE adopts a similar approach, with a solution designed to provide a wireless connection between the system’s AMATRON+ virtual terminal and the PC on the farm via an electronic calendar (or as a direct link between two units provided the distance between them is no more than a few dozen metres when the data is being transferred).
It is worth noting that RM. MICHAELIDES also produces a solution that uses Bluetooth communications between an on-board CAN network (CANopen) and an electronic calendar or PC. This CANView/Bluetooth solution provides coverage from around 20 m (class 2) up to 100 m (class 1).
2- Still only one example of a control application
We have also identified new applications using the Bluetooth communications standard for command/control purposes in addition to the device produced by the Austrian company POTTINGER already referred to and developed in partnership with WTK ELECTRONIK. Offered as an optional extra across its full range of self-loading fodder harvesting trailers (FARO, EUROPROFI, etc.), the device can be used by the driver to run various of the machine’s functions (e.g. opening the rear door) away from the cab within a radius of 10 m from the trailer.
fig. 8 – Bluetooth control device
(source WTK ELECTRONIK)
WLAN – WIFI technologies still at the Research & Development stage
Although WLAN (Wireless Local Area network) and WIFI (Wireless Fidelity) technologies have grown spectacularly in public places (airports, railway stations, hotels, etc.) to connect laptop computers to the Internet over a wireless connection, and at home to increase the number of home automation applications able to communicate with each other, we have not found any applications being marketed for mobile machinery incorporating this technology. Only the electronic equipment manufacturer RM has a CANview/WLAN (802.11b standard) interface card in its catalogue. Use of these technologies is therefore still at the research and development stage. As this is clearly a communications medium with enormous potential, it seems worth examining one example identified on the University of Braunschweig stand and another based on the current work being done by the COPAIN team at Cemagref in Clermont-Ferrand.
1- Example of work at the University of Braunschweig
Two teams from the University of Braunschweig (Germany) took part between 2002 and 2005 in a research project supported by the German government and involving the manufacturing firm CLAAS on optimising silage depots in general and optimal control of trailer filling in particular. Photo 2 below gives a general idea of the demonstration model produced.
Photo 2 – Automatic control of a transport vehicle from a harvesting machine
(source University of Braunschweig)
The aim is to manage filling of the trailer on the transport vehicle through real-time control of the direction of the flow of product coming out of the chopper-blower. The tractor, equipped with three GPS sensors in the cab, uses a WLAN-WIFI connection to transmit raw positioning data to a calculator on the harvesting machine. The calculator extracts the relative position of the tractor (lateral displacement, heading, speed) compared with the chopper-blower, which has its own GPS receptors. The position of the trailer is estimated based on a visual display of the tractor-trailer combination. At the same time as managing the position of the chute to direct the flow of silage correctly, the system communicates information to a screen in the tractor over a WLAN telling the driver, for example, to speed up or slow down the speed of the vehicle.
2- Example of work by the Research Federation: Information, Mobility and Safety Research (FR TIMS) - Cemagref-LIMOS
The work carried out by the FR TIMS is on developing a multimedia communications protocol (WIFI (IEE 802.11x), Bluetooth, ZigBee) taking into account the spatial distribution and development context of vehicles (in particular based on GPS location calculation) and on providing a guaranteed quality of service through control of the wireless communications networks resources available. This Cooperative Intelligent Inter Vehicle Communications protocol (CIVIC) is incorporated in a basic microcontroller module that operates as a dedicated network card (eCIVIC) and can be used transparently by various on-board processing units. Directional antennas that can be linked to the position of a vehicle in order to increase the transmission range of WiFi communications have also been examined.
The aim of the research is not so much to create an ad hoc link between two machines or between one machine and a set of infrastructure but to have a communications link to the farm and the Internet available on a permanent basis (see photo opposite). The networks used to achieve this are ad hoc, i.e. not linked to any specific infrastructure: each node on the network is used to relay information, which therefore reaches the recipient via a series of short steps.
Research is being carried out on various aspects of using networks of this kind, such as developing routing protocols appropriate to the specific characteristics of the rural environment, creating networks of sensors to collect data and increase the density of nodes in the network, and Internet access via satellite in rural areas.
Regulation and standards - questions on the use of wireless technology in agricultural equipment
Wireless technologies are developing rapidly and, in addition to applications designed purely for the transmission of operational data, they could be developed to play a more important role in the near future in controlling mobile machinery or even in operator protection systems. Uses of this kind necessarily raise the question of the safety of the user and their environment.
In regulatory terms at least, two European Directives are applicable to devices of this kind incorporated into machinery: The Machinery Directive 98/37/EC and the Electromagnetic Compatibility (EMC) Directive 89/336/EEC. The main aim of the EMC Directive is to guarantee the free movement of devices and to create an acceptable electromagnetic environment across the European Union. To achieve this, the Directive requires a harmonised and acceptable level of protection based on article 100a of the Treaty on European Union. The level of protection is defined in the Directive by protection targets in the area of electromagnetic compatibility, the aims of which are to:
- ensure that electromagnetic disturbance produced by electrical and electromagnetic devices does not affect the proper operation of other devices, as defined in article 1.1 of the EMC Directive, as well as radio communications and telecommunications networks, the corresponding equipment and electricity distribution networks.
- ensure that devices have an adequate level of intrinsic immunity in relation to electromagnetic disturbance, enabling them to operate as intended. The EMC Directive sets out protection and procedural requirements to achieve these objectives.
Developed in accordance with the EMC Directive, ISO standard 14982 (Agricultural and forestry machinery – electromagnetic compatibility – test methods and acceptance criteria) specifies testing methods and sets out the criteria for assessing electromagnetic compatibility. Its scope includes tractors and all types of agricultural and forestry machinery and mobile landscaping and gardening machinery. It also covers electrical and electronic components and sub-assemblies designed to be incorporated in these types of machinery. It therefore seems likely that wireless technologies included in machinery of this kind will be assessed according to the terms of this standard.
The so-called Machinery Directive 98/37/EC also applies to components associated with a machine. The aim of the Directive is to incorporate safety at the design stage in order to ensure that the machine is suitable to operate as intended and can be adjusted and maintained without people being exposed to risk when these operations are carried out in accordance with the manufacturer’s instructions. The level of protection is specified in annex I, which sets out essential health and safety requirements.
As soon as wireless technology is used in a machine process, a risk assessment will have to be carried out. If it is incorporated in a control system for a safety function, an iterative analysis will have to be carried out in based on the following design (cf. fig. 9) introduced in Draft EN ISO 13849-1: 2004 (Safety of machinery – safety related parts of control systems – Part 1: General principles for design)
fig. 9 – Draft EN ISO 13849-1: 2004
The design of a safety-related control system is therefore not an easy task, which is why a number of standards have been produced to help designers: standard NF EN 954-1 (Safety of machinery – safety related parts of control systems) is one of them. Standard NF EN 954-1 specifies that the more the reduction of risk depends on the safety-related parts of the control system, the higher their resistance to defects must be (according to EN 954-141: 1996 § 4.2). As a result, it is necessary to take measures to reduce risk. The main measures are as follows:
- reduce the probability of defects at the level of the component. The aim is to reduce the probability of defects or failure modes that have an impact on the safety function. This can be achieved by increasing the reliability of components, for example by selecting tried and tested components and/or applying tried and tested design principles in order to eliminate the appearance of defects or critical failure modes.
- Improve the structure of the system. The aim is to avoid a dangerous effect as the result of a defect. Certain defects may be detected and a redundant and/or monitored structure proved necessary.
In addition to its ability to meet reliability objectives, this technology raises the issue of being able to control the machine from different places. The spatial limitations on the operability of certain controls needs to be checked by means of a risk assessment. The concept of a “control device installed outside hazardous areas” is much more difficult to assess. Directive 98/37/EC states in § 3.3.3 of Annex I that “remote-controlled machinery must be designed and built to stop automatically if the driver loses control” (see also standard CEI 60204-1: 1997 § 9.2.7 “Safety of machinery – electrical equipment of machines – Part 1: General requirements).
Insofar as machines now include more and more electrical / electronic / programmable electronic and automated components, the operational safety of these systems is becoming more and more difficult to manage. A significant amount of work is underway within ISO TC 23 SC 14, particularly with regard to the treatment of electrical / electronic and programmable electronic safety systems (to be continued, particularly at the next SIMA).
- Roger Lane-Nott, The 22 July 2010 16h15 I am the CEO of the Agricultural Engineers Association in UK. (www.aea.uk.com) We represent manufacturers of Farm Equipment and Outdoor Power Equipment and we are always looking for new ideas and technology. We would be happy to consider ways of helping to promote your research and technology. If we can be of assistance please contact me.
