Add TYPE_TRUCK to vehicle classifications

[caspar-ai]

To align with OpenSCENARIO and OpenLABEL. Also deprecate the use of TYPE_HEAVY_TRUCK and TYPE_SEMITRAILER as ambiguous.

For more details see #583.

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[caspar-ai]

Not sure who is best placed to review this.

@adrianschultz as you recently added an issue about vehicle classification I'm starting with you :) please feel free to reassign, or add people, if you think they are better placed or would be interested.

Also, I realise I've raised a few harmonisation issues recently, if it would be helpful for me to come along to a harmonisation working group meeting do drop me an invite.

Thanks!

[caspar-ai]

@pmai or @kmeids do you know who might be best placed to review this suggestion / discussion?

Or if it would make sense for me to attend a particular WP or architecture meeting to discuss, do drop me an invite.

[caspar-ai]

Adding the ReadyForCCBReview as a means for getting some eyes on this and how to progress it forwards.

[stefancyliax]

OSI CCB 10.11.2021:

• After discussion about classification of trucks and trailers, we would propose another solution.
• Proposal:
  SemiTrailer -> improve comment, type describes only trailer without truck
  SemiTractor -> new type to clarify pulling part of semi-truck
  AgricaturalVehicle -> new type for farm vehicles
  HeavyTruck -> should be kept, don't add new type TRUCK

Please also add info about mapping to OpenSCENARIO.
Please also evaluate which types would benefit from a example picture. (e.g. Deliveryvan, Semitrailer, Semitractor, HeavyTruck, ...)

[caspar-ai]

I've done as suggested and added semi-tractor, rather than removing semi-trailer.

I've also tried to write down the mapping for each type to its OSC 1.x and 2.x counterparts. In particular, it is worth noting that OSC 2.x (and also OpenLABEL I believe) while both still being defined, they seem to be going the way of a few broad types rather than more narrower types.

It sounds like consensus is that there is value in OSI have a richer set of vehicle types than OpenScenario / OpenLabel. I would strongly encourage that reasoning to be captured within the OSI definitions as a record for future users and a more permanent record of these discussion. I'm not sure what the reasoning is, so I've left a placeholder for now.

@HendrikAmelunxen is that something you can provide based on the last CCB discussion?

[HendrikAmelunxen]

Suggestion:
This vehicle is a semi-trailer that can be pulled by a semi-tractor.

Definition: A semi-trailer is a trailer without a front axle. The front part of the semi-trailer is mounted on the semi-tractor which leads to a significant overlap of the bounding-boxes of semi-tractor and semi-trailer.

[caspar-ai]

I'd have thought most trailers don't have a front axle? A quick google search of "car trailer" suggests most have only rear or mid axles.

Perhaps the distinction is instead weight or size rather than axles or joining mechanism / overlap?

[HendrikAmelunxen]

There are different trailer types, e.g., trailers with one axle in the middle or a tandem trailer. These are mainly towed by vehicles or agricultural vehicles.
Trailers towed by trucks mostly have either a front and a rear axle (often referred to as “full-trailer”) or just one or more rear-axle(s) (“semi-trailer”). The semi-trailer is towed by a semi-tractor, which is not able to carry additional loads, but its only purpose is to tow the semi-trailer. “full-trailer” can be towed by trucks or agricultural vehicles. One specialty is a dolly, which is an adapter to couple semi-trailer to trucks or agricultural vehicle or generate road trains consisting of semi-trailers. This dolly variant transforms semi-trailers into full-trailers and should be handled like full-trailers.

I think semi-trailers should be handled with a separate type since they are widely used and have special characteristics due to their coupling mechanism. In that regard, it also makes to have semi-tractors as separate types to describe the pulling part for semi-trailers.

It might be reasonable to introduce the full-trailer as an additional trailer variant. By this we would have:
full-trailer: for big trailers with front and rear axle
Semi-trailer: for semi-tractor + semi-trailer couplings
Trailer: describing the general vehicle trailers

Would that be an approach?

[caspar-ai]

As discussed in the harmonisation meeting. This is a complex area and trying to define precise boundaries between types is more than we want to take on as part of this PR which is primarily about clarifying semi-trailer / tractor definitions.

As such, I have remove any new attempts at defining boundaries, and I have written a note in the top level enum comment indicating that the imprecise boundaries are deliberate and left to the implementor to decide on in their specific use case.

Does that work for you?

[stmswald]

Nice work, how about adding additional visual descriptions?
This could help to decide what type of car/truck/etc.

like:

ref: DOI: 10.1109/JSEN.2021.3115589

[thempen]

As we have discussed it in the last Harmonization group meeting, two points:

• The OpenSCENARIO 1.x and 2.x references should be specific versions, like OpenSCENARIO 1.1 and 2.0. We do not know how it will change in the future.
• We have now multiple points in the whole documentation with references to OSC and ODR. I am not exactly sure how many and to which standards we have mappings. I have concerns in future maintenance with these references, because of the changes in the referencing documents. As we have suggested in Best-Practice Guide #500, we could write Best-Practices guides for, e.g. the usage with OpenSCENARIO or OpenDRIVE to bundle the information about connections. Perhaps it could be some WP for 4.0.

[caspar-ai]

Nice work, how about adding additional visual descriptions? This could help to decide what type of car/truck/etc.

like: ref: DOI: 10.1109/JSEN.2021.3115589

We can do these, but given we already know there are fuzzy boundaries and are saying defining the boundaries is left as an exercise for the user, I don't know if it is correct to try and then add guides which do try and precise the boundaries.

[caspar-ai]

As we have discussed it in the last Harmonization group meeting, two points:

• The OpenSCENARIO 1.x and 2.x references should be specific versions, like OpenSCENARIO 1.1 and 2.0. We do not know how it will change in the future.
• We have now multiple points in the whole documentation with references to OSC and ODR. I am not exactly sure how many and to which standards we have mappings. I have concerns in future maintenance with these references, because of the changes in the referencing documents. As we have suggested in Best-Practice Guide #500, we could write Best-Practices guides for, e.g. the usage with OpenSCENARIO or OpenDRIVE to bundle the information about connections. Perhaps it could be some WP for 4.0.

Removed all references to OSC.

[stmswald]

Nice work, how about adding additional visual descriptions? This could help to decide what type of car/truck/etc.
like: ref: DOI: 10.1109/JSEN.2021.3115589

We can do these, but given we already know there are fuzzy boundaries and are saying defining the boundaries is left as an exercise for the user, I don't know if it is correct to try and then add guides which do try and precise the boundaries.

OSI Harmonization Group 12/7/2021 Ideas for Outline shapes

[caspar-ai]

@stmswald those outlines look good to me.

[HendrikAmelunxen]

@stmswald I think that helps to distinguish between the different trucks and trailer types. Maybe an additional shape for the trailer makes sense, like

[caspar-ai]

@stmswald / @HendrikAmelunxen what's the next step here? I'm assuming we need to turn those outlines into .svg files, add them to this PR and reference them from the comments so that they appear in the documentation.

Is one of you looking at doing that?

[caspar-ai]

After discussing with @stmswald via email we think it would be good to get review from the CCB.

There are two things which we are unsure about with the documentation images that it would be good to get some feedback on from the CCB.

1. Are the images too big? They are .svg files so can be scaled as needed, but I don't know if doxygen allows scaling hints, so do the uploaded images need to be set with a smaller default size? Or are they OK as-is?
2. Do the images need to conform to a consistent style? For example, many are done with black and white outline drawings. Are there specific people, or tools, that are used to ensure a consistent style?

[HendrikAmelunxen]

@caspar-ai Currently the images are too big, and I think it would make sense to have them in black and white in order to be more aligned with the other images. I think, a styleguide for images does not exist though.

I think it would make sense to scale the images down and make them in black and white. After that it would make sense to contact CCB.

[caspar-ai]

Fixed up the images to be both smaller, and black outline drawings. Given no particular style I've gone for the slightly "hand drawn" style using https://excalidraw.com/ hopefully they are OK.

Adding back in the CCB label based on the comment above, but let me know if you think they need tweaking again first.

[kmeids]

Output CCB 02.03.2022:

1. @pmai to merge this.