Matthias Meyer / Jaap van Bergeijk | October 2009 Page 1 AEF Engineering and Implementation, training

Matthias Meyer / Jaap van Bergeijk | October 2009 Page 1

AEF Engineering and Implementation, training



Task Controller Interface

• Most Common Issues• Section Control Example



TC interface, most common issues

• Start of communication– TC Version Number

• Check if you want to use features that came around in a certain version.

• Backwards compatibility is very, very important.

– CF Network NAME• Ensure that the NAME of the device on the network that

uploads the device descriptor is the same as the NAME that identifies the device descriptor.




• Device Descriptor Structure– What’s the uniqueness of the structure label?

• The structure and number of device elements• The device property values

– Reload a DD-pool?• Smart option: upload the DD root element with a new

structure label and the objects that changed.• Brute Force option: upload entire pool when a property value

is modified or when the number or structure of device elements has changed.

– In any case: hash the structure label.




• Device Descriptor Localization– What’s the uniqueness of the localization label?

• Designators and device value presentation objects.

– Reload a DD-pool?• Smart option: upload the DD root element with a new

localization label, update the designators and upload the device value presentation objects that changed.

• Brute Force option: upload entire pool when language or units in a system change.

– In any case: mark the localization label correctly.




• Task Totals (Counters)• Observe TC status, don’t mix up order of CAN messages.

– Task Totals from Inactive to Active• ECU’s reset totals and start counting• TC may send total values to resume from

– Task Totals from Active to Inactive• ECU’s retain total values• TC queries total values

• All good but what if electrical power is cut off?– TC to request and store totals regularly?




• Measurements, DefaultDataLogTrigger– Meant to be a “device controlled datalog method”.– Issues:

• Not linked to root device element• Not formatted right (B=“DFFF” C=“0” D=“31”)• Not requested upon task start (command = 2)

– Combine or override existing measurements?• Combine, latest command wins in case of conflicts

– Mechanism isn’t limited to Data Logging.• Just reset on Task Totals Active going to Inactive.




• Process Data communication– Why did it move into Part 10?

• Consolidation of device descriptor handling.• Need the device structure to make sense of it.

– Doesn’t mean you can’t use it outside TC-WS communication. So: you’d better filter on SA…

– Process Data commands (including measurements) were meant to be used independent of Task Totals Active state.

– Individual measurements can be stopped (see D.14 DataLogTrigger definition for stop values).




• XML interface– Too many optional items

• AEF groups are tackling this with functionality groups.

– Version Major / Minor in file header?• Major to follow ISO11783-10 version, minor free to

use?



Task Controller Interface

• Most Common Issues• Section Control Use Case



TC Based Section Control

• System Feature– Builds upon Task Controller communication

• Device descriptor to specify implement details.• Process Data to monitor and control sections.

– Needs additional definitions to make it work seamless for the operator

• Task Controller operator interface could be totally different from an implement’s operator interface.

• Implement internal state could inhibit this function temporarily.

• What is manual mode and what is automatic control?

– Can it run independent of Task Totals Active?



TC Based Section Control

• Added Definitions– Data Dictionary (ISO11783-11)

• Section Control State• Condensed Work States



These slides give some background information on the object structure in Task Controller Device Description Data (DDD)

The following Subjects are covered:– Section Control State DDE (SCS)

– SCS on Single Boom Sprayers

– SCS on Dual Boom Sprayers

– Condensed Work State DDE (CWS)

– Examples for CWS

Note: The examples are based on sprayer, but planters, seeders or any other section/row based implement should be configured in a similar way.


AEF Engineering and Implementation, trainingGeneral Information for the following examples

The DDI’s listed on this page are used in the following examples

1 = Setpoint Volume Per Area Application Rate

2 = Actual Volume Per Area Application Rate

67 = Actual Working Width

80 = Application Total Volume

116 = Total Area

117 = Effective Total Distance

119 = Effective Total Time

134 = Device Element Offset X

135 = Device Element Offset Y

141 = Work State ON/OFF

DeviceObject DVC

DeviceProcessDataObject DPD

DeviceElementObject DET

DevicePropertyObject DVP

DeviceValuePresentationObject DVP

Object hierarchy and color coding for the following examples


AEF Engineering and Implementation, trainingSection Control State DDE

In section control systems the master and clients need to be synchronized in terms of their general state or activation by the operator. This DDE allows the clients to announce the support and preset state of section control in their Device Configuration Data. The Section Control master (TC) can send its state as prescription value while it is recommended for the client to respond with its state immediately (within 250 ms). The property flag “setable” and the trigger method “on change” should be set to 1.

The state ‘manual/off’ (00) means that the implement is in manual state and will ignore all control commands for section control. In ‘auto state’ (01) the client accepts the control commands for section control.

The Section Control State DDI should be attached to any DeviceElementObject above objects representing sections. The related sections need to have either the Work State DDI (141) attached and/or the proposed Condensed Section Work State (TBD) is linked to the direct parent of the reflected section objects.



DVC

Sprayer (DET - device)

CRP (DET – connector)

x-offset y-offset

Section (DET – section)

width y-offset

DVP DVP


width y-offset

DVP DVP

DVP DVP

Section (DET- section)

width y-offset

DVP DVP

1 2 80 116 SCS

z-offset

DVP

x-offset

DVP

z-offset

DVP

x-offset

DVP

z-offset

DVP

x-offset

DVP

z-offset

DVP

DVP DVP DVP DVP

117

DVP

119

DVP

141

Proposal for a Device Description Data with Section Control State.Single boom sprayer. Boom is not defined as individual object

x-offset

DVP

141141141

width

DVP



DVC

Sprayer (DET device)


width y-offset

DVP DVP


width y-offset

DVP DVP

width y-offset

DVP DVP

1 2 80 116

141 141 141

DVP DVP DVP DVP

117

DVP

119

DVP

Boom (DET – function)

Proposal for a Device Description Data with Section Control State.Single boom sprayer. Boom represented by a device of type function

x-offset

DVP

141



x-offset y-offset

DVP DVP

z-offset

DVP

x-offset

DVP

z-offset

DVP

x-offset

DVP

z-offset

DVP

x-offset

DVP

z-offset

DVP

width

DVP

SCS


AEF Engineering and Implementation, trainingProposal for a Device Description Data with Section Control State.

Dual boom sprayer. Booms are represented by devices of type function

DVC

Sprayer (DET – device)

Section 1 (DET – section)

141 width y-offset

DVP DVP

x-offset

DVP

Boom 1 (DET - function)

141 SCS x-offset

DVP

DDI A-N

Boom 2 (DET – function)

141 SCS x-offset

DVPDVP

Section n (DET – section)

141 width y-offset

DVP DVP

x-offset

DVP


141 width y-offset

DVP DVP

x-offset

DVP

Section n (DET – section)

141 width y-offset

DVP DVP

x-offset

DVP

width

DVP

width

DVP

DDI A-N

DVP


x-offset y-offset

DVP DVP

z-offset

DVP



Condensed Work State will reduce the traffic on the CAN bus, because one message covers multiple sections states.

Especially for data logging this allows a reduction of the busload. For instance, 16 section states have to be logged with a frequency of 5 Hz. Without Condensed Work state 16 messages are every 200 ms required. With Condensed Work State only one message every 200 ms is needed. With the increasing number of sections this becomes more and more an issue.

The Condensed Work State combines many individual section work states into a single representative work state attached to the parent object.The condensed work state will be populated by taking the individual work states, in the driving direction from left to right, while the most left work state is represented by the lowest bits of the Process Variable Value (see ISO11783-7 'Process Data parameters' for details).Each work state is represented by 2 bits as defined in ISO11783-7 'General requirements and recommendations': 00 = disabled/off, 01 = enabled/on, 10 = error indicator, 11 = undefined/not installed

Condensed Work State



DVC



width y-offset

DVP DVP


width y-offset

DVP DVP


width y-offset

DVP DVP

DDI A DDI N SCS

x-offset

DVP

z-offset

DVP

DVP DVP

141 xoffset

DVP

141141141

Condensed Work StateSingle boom sprayer example. The boom is not defined as individual object


X

Y

x-offset

DVP

z-offset

DVP

x-offset

DVP

z-offset

DVP


x-offset y-offset

DVP DVP

z-offset

DVP

width

DVP


AEF Engineering and Implementation, trainingProposal for a Device Description Data with Condensed Work State.

Single boom sprayer. Boom represented by a device of type function

DVC


x-offset y-offset


width y-offset

DVP DVP


width y-offset

DVP DVP

DVP DVP


width y-offset

DVP DVP

DDI A

Boom (DET - function)

DDI N y-offsetSCS x-offset

DVP DVP

z-offset

DVP

z-offset

DVP

width

DVP

x-offset

DVP

z-offset

DVP

141

141 141 141



x-offset

DVP

z-offset

DVP

x-offset

DVP

z-offset

DVP

X

Y



DVC


x-offset y-offset


width y-offset

DVP DVP


width y-offset

DVP DVP

DVP DVP


width y-offset

DVP DVP

DDI A

Boom (DET – function)

DDI N y-offsetSCS x-offset

DVP DVP

z-offset

DVP

z-offset

DVP

width

DVP

x-offset

DVP

z-offset

DVP

x-offset

DVP

z-offset

DVP

x-offset

DVP

z-offset

DVP

141

141 141 141

Condensed Work State 1 -16 Condensed Work State 17-32

Condensed Work StateExample for more than 16 sections per parent

Single boom sprayer. Boom represented by a device of type function


* * *

X

Y



DVC



width y-offset

DVP DVP


width y-offset

DVP DVP


width y-offset

DVP DVP

DDI A DDI N SCS

x-offset

DVP

z-offset

DVP

x-offset

DVP

z-offset

DVP

x-offset

DVP

z-offset

DVP

141 141 141

Condensed Work State 1 -16

* * *

Condensed Work StateBit order for a single boom sprayer

x-offset

DVP

Condensed Work State 1 -16 141

X

Y

x-offset y-offset

DVP DVP

z-offset

DVP

CRP (DET – connector)width

DVP



Questions?

Documents

Matthias Meyer / Jaap van Bergeijk | October 2009 Page 1 AEF Engineering and Implementation, training