Working draft of the amendments to introduce provisions for automated connections bewteen vehicles into UN R13 pursuant to the discussions held during the 6th informal group meeting of 28-29 February 2012.
Provisions for mismatching between 12/24 volt
The conclusion of last time was that we need not do anything on this point as the only mixed market is Australia and Australia do not have any problem. In Europe this concerns very few vehicles only.
Measuring response time
Jost did some tests with TÜV and confirms that the way of measuring in annex 6 is sufficient. In annex 6 point 3.3.3. we need to add not less than 10mm “except for the connector”.
Solid connection of hoses
After discussion, the group decided that there was no need to handle cables that are not in use.
In the case of a tractor, flexible hoses are part of the tractor according to annex 6, paragraph 2.5. For full trailers they are part of the trailer.
The group was of the opinion that this point does not need to be discussed any further, the driver has to come out of his cab.
We need to add to R13 that flexible hoses are not needed for ACV’s.
For wording of paragraph 5.1.3.8. see document ACV-07-04.
Length of EBS cables
12 to 13m is standard on the majority of vehicles but some suppliers sell also 16m. For special trailers that need extra length repeaters are used.
The group is to verify two points:
Driver warnings
The same signals and warnings available today remain.
With an automatic connector the driver has no ‘feel’ that the connection is good. In that case he shouldn’t drive the combination.
The electrics need to be engaged before the pneumatics are engaged. VBG are of the opinion that we must focus on alarming any risk of losing the trailer. This could introduce a lot of control that we don’t have with a conventional coupling. We should get a light when the connection is well made and a red light if it is not well made plus a message from the trailer. Question is what kind of message.
Jost propose a red light when the connection is open until the connector is mechanically properly closed and then we should get a green light.
An automated connector is much safer than a convential connection. We can give additional information also but must develop this together with the OEM.
The group agrees that we must have a signal that the connection is closed. We must say that the electric connections must come first but this is design restrictive. Or, alternatively it must not be possible to move the combination if the connection is not properly closed.
A warning system is an improvement over what we have today. If something is wrong we must have a permanent warning.
The various working documents submitted for this meeting were discussed in detail. For the outcome of the discussions, please see document ACV-06-10.
Provisions for mismatching between 12/24 volt
The group went through the 12/24v document from Jost. In Australia most trailers are 12v. The group concluded that this working group does not need to make mention of this at all as the situation is not critical.
Measuring response time
Jost made some measurements. Response time of an ACV is lower than with a helix cable. When we are measuring with a simulator, we have to measure the supply system. We need a set of rules for the conventional system (annex 6) and a set of rules for the automated system.
If volume L in annex 6 is left then we have a problem. A valve adds 0.06s. We need to change the volume in annex 6 for the automated system.
If the connection line between truck and trailer is different then this must be taken into account. We actually need a longer length.
The group agreed that the method as outlined still applies but there are open issues:
- Is there room for a different value of L? If the volume L is changed then it must be changed in the calibration also.
- Timing is a secondary issue. We know the measurement is good but we don’t know how it should be changed.
Solid connection of hoses
This item was not discussed.
A point for the next meeting : think about a manual button that would make the driver leave his cab.