Turning Path - Equestrian

[ACADuser]

Does anyone have or know where I could find autocad drawings showing turning paths for trucks pulling horse trailers ? An assortment of different horse trailers would be ideal (1 horse, 2 horse, tag-a-long, gooseneck, etc.). We are in the early planning stages for several equestrian parking areas and need to determine what configurations would work best for each site.

Any help would be appreciated.

[Anonymous]

Hi,

Plan for the biggest one with the worst driver - everything else will be
OK then. They will often be driving on soft surfaces were the templates
do not apply and the swept paths will be wider and occur later after the
steering wheel movement starts.

The drivers will not always be particularly skilled and you need to
allow extra clearances for that purpose

If you really need to be pedantic about it, then get yourself a copy of
Autotrack from http://www.savoy.co.uk/

There is also quite a lot of data available if you google "Turning circle"


Regards,


Laurie Comerford

ACADuser wrote:
> Does anyone have or know where I could find autocad drawings showing turning paths for trucks pulling horse trailers ? An assortment of different horse trailers would be ideal (1 horse, 2 horse, tag-a-long, gooseneck, etc.). We are in the early planning stages for several equestrian parking areas and need to determine what configurations would work best for each site.
>
> Any help would be appreciated.
>

[Anonymous]

Look into a program called AutoTurn from Transoft, I think. They have different vehicles to choose from, different turning templates and a steer path options that you can animate forward and reverse. Have personally used and would recommend.

[ACADuser]

Update

Attached is a drawing I created that includes several turning paths of trucks pulling several differnt types of horse trailers. Included is a dynamic block with each truck/trailer combination. And gives the ability to rotate the truck/trailer as a whole and in independant of each other (via grips).

The turning paths were created using Turn.lsp version 1.1.7 developed by HawsEDC. The lsp is free and can be downloaded from their website. Within the drawing I have created a separate set of blocks representing each of the truck/trailer combinations that can be used with the lsp program. Draw a pline representing the path of your vehicle and use the lsp to create the path of each wheel, very cool.

Hopefully this will be useful to others.

ACADuser

[Anonymous]

Hi ACADuser,

The work you have dne for this and publishing for all to use is
appreciated. Before the templates are fully functional it is desirable
to know the following.

What sort of surface are these templates designed for - ashphalt,
gravel, dry grass, wet grass, mud?

What speed are they designed for - highway, car park, 'hoons in action'?

Are the towing vehicles in two wheel drive, rear wheel drive, front
wheel drive?

What are the relative weights on the trailers and towing vehicles?

Are the trailers single or dual axle?

All these factors have significant influences on the turning circles.

Without having studied "Turn.lsp" my guess is that it would predict the
theoretical turning circle assuming no slip any where and hence the
predicted turning circle could be far smaller than the ones experienced
in real life.

Regards,

Laurie Comerford


ACADuser wrote:
> Update
>
> Attached is a drawing I created that includes several turning paths of trucks pulling several differnt types of horse trailers. Included is a dynamic block with each truck/trailer combination. And gives the ability to rotate the truck/trailer as a whole and in independant of each other (via grips).
>
> The turning paths were created using Turn.lsp version 1.1.7 developed by HawsEDC. The lsp is free and can be downloaded from their website. Within the drawing I have created a separate set of blocks representing each of the truck/trailer combinations that can be used with the lsp program. Draw a pline representing the path of your vehicle and use the lsp to create the path of each wheel, very cool.
>
> Hopefully this will be useful to others.
>
> ACADuser

[Savoy]

Laurine,

From memory turn.lsp does not take into account and "steering controls" or "turn transitions" of the vehicle, all it does is assume the pline it is following is a valid route, this is fine where the turns are large but once you start to model a tight turn just asumming that the pickup can follow a 5m arc on a pline is not good enough. Lots of these type routines also assume that the wheels can turn instantly, which means the resulting path will incur a lot of scrubing.

When calculating the vehicle movement to produce the swept path a turn transition needs to be calculated this is generally done by taking into account how fast the steering wheel can be turned and calculating a turn spiral, this calculation is further complicated if the vehicle has rear steering or differing numbers of wheels per axle.

AutoTrack takes into account over a dozen parameters when calculating turn transitions and how the trailers behave. All the factors are applied when driving in forwards and reverse.

A demo of AutoTrack can be downloaded from www.savoy.co.uk

Nigel Peters
Savoy Computing Services Ltd

[lsimms1]

Good job.
As a horse owner that does some travelling with my horse it looks to be pretty realistic. I would allow a bit more for the minimum turning radius. Maybe an extra 1m (3').
The reason for this is the horses move around a bit shifting their weight. This could cause the trailer to swing a bit more. Also, if the trailer is empty it could bounce a bit over a bump.

[ACADuser]

The templates were not designed for a particular type of surface and do not take into account all of the parameters that may affect the path of each wheel. They were developed to give a general idea of turning paths for trucks pulling horse trailers so as to determine parking arrangements for each site that will accommodate equestrian and passenger vehicle parking. Some of the sites are very narrow and only allow for smaller trailers (single or two horse trailers), thus the reason for several types of truck/trailer combinations.

For those that care to know, the following was used as a basis for design of the vehicle and trailer:
Dimensions and minimum turning circle for the truck; 2011 Ford Super Duty (crew cab, LWB, F-250 SRW and F-350 DRW).
I selected trailers that would cover the range of different parking scenarios that I need to design for. Because there is such a wide variety of manufacturers and types of horse trailers, I tried to use the larger dimensions of those that I was able to obtain.

After defining the blocks, I developed the turning templates using the minimum turning radius of the design vehicle while also maintaining an angle of 120°+ between the truck and trailer (this is common for most tow vehicles and trailers). It was an iterative process for each truck/trailer combination. Starting with the minimum turning radius and generating a turning path using the lsp I then checked that the truck and trailer could track along the path while maintaining the 120°. If the truck/trailer was not able to follow the path and maintain the 120°, I would then increase the turning radius and perform the process again until the conditions were met.

While this may not be the most accurate method, it does provide a solution to the problem we were facing.

[Anonymous]

Hi ACADuser,

This is a great explanation of your work and its strengths and weaknesses.

For an expansion of the points I raised you may care to look at
Autotrack (see Nigel's post above). I used to work for a dealer who
sold Autotrack so have some knowledge of the software as it was several
years ago, as well as practical experience dealing with a wide variety
of vehicles up to a 30m long by 8m wide 15 axle push and pull trailer
for carrying 300 tonne loads.

Had you used Autotrack you could have used it's tools to add your
vehicle/trailer combinations and produce the turning circles with far
less work.

Regards,

Laurie Comerford


ACADuser wrote:
> The templates were not designed for a particular type of surface and do not take into account all of the parameters that may affect the path of each wheel. They were developed to give a general idea of turning paths for trucks pulling horse trailers so as to determine parking arrangements for each site that will accommodate equestrian and passenger vehicle parking. Some of the sites are very narrow and only allow for smaller trailers (single or two horse trailers), thus the reason for several types of truck/trailer combinations.
>
> For those that care to know, the following was used as a basis for design of the vehicle and trailer:
> Dimensions and minimum turning circle for the truck; 2011 Ford Super Duty (crew cab, LWB, F-250 SRW and F-350 DRW).
> I selected trailers that would cover the range of different parking scenarios that I need to design for. Because there is such a wide variety of manufacturers and types of horse trailers, I tried to use the larger dimensions of those that I was able to obtain.
>
> After defining the blocks, I developed the turning templates using the minimum turning radius of the design vehicle while also maintaining an angle of 120°+ between the truck and trailer (this is common for most tow vehicles and trailers). It was an iterative process for each truck/trailer combination. Starting with the minimum turning radius and generating a turning path using the lsp I then checked that the truck and trailer could track along the path while maintaining the 120°. If the truck/trailer was not able to follow the path and maintain the 120°, I would then increase the turning radius and perform the process again until the conditions were met.
>
> While this may not be the most accurate method, it does provide a solution to the problem we were facing.