Calculating and Drawing Vehicle Turning Circles

[j4cksincl4ir]

This is more of a geometrical question rather than an AutoCAD one.

 

I am designing a piazza that most types of vehicles need to circumnavigate. On a scaled location plan, I would like to draw the scaled turning circles of cars and lorries - especially emergency vehicles.

 

I have the Metric Handbook beside me which has typical 90 degree turns drawn but it is not obvious how they were drawn in the first place.

 

I have all the vehicle dimensions that I need, I just need to know how to calculate and draw the geometry.

 

Does anyone have ideas?

[ReMark]

LT? Too bad. CadTools has a vehicle turning simulation feature that would probably do the trick. Unfortunately the user needs to be running full AutoCAD.

[RobDraw]

A quick search on Google got this http://truckalignment.com/turnrad.html and many other resources.

[Organic]

This is more of a geometrical question rather than an AutoCAD one.

 

I am designing a piazza that most types of vehicles need to circumnavigate. On a scaled location plan, I would like to draw the scaled turning circles of cars and lorries - especially emergency vehicles.

 

I have the Metric Handbook beside me which has typical 90 degree turns drawn but it is not obvious how they were drawn in the first place.

 

I have all the vehicle dimensions that I need, I just need to know how to calculate and draw the geometry.

 

Does anyone have ideas?

 

Print the turning templates out to scale (ideally print them on clear laminate sheets). Then print your piazza layout out to scale. Then just place the turning templates over top (hence why the laminate sheets are easier, otherwise use a lightbox or a window) and move them through your design. It is the old school way to check the design works.

 

If you are doing a significant design however or require overlaid sweep paths to be presented for approval, I'd recommend you buy AutoTurn or AutoTrack (these probably do require full AutoCad though, not sure; AutoTrack is the better of the two in my opinion). AutoTrack can be hired out for a few days etc if you don't want to purchase it outright.

[BIGAL]

If your running Autoturn or similar then you can save typical turning movements as Autocad dwgs, just like printing them out.

[ArqCastro]

In my previous company they used a specific program with autocad, AUTOTURN, it draws that (it's a paid program...)

[ffuuzzyyllooggiicc]

Hi,

 

This is an old post now but I have been looking for info on vehicle turning circles and more complex manoeuvres. It's a lot more complex than I'd imagined! It would seem people used to use templates (due to the complexity of the calculations and specific vehicle characteristics involved). More recently people use dynamic software. There are also consultancies who undertake Swept Path Analysis, so that really shows how complex the subject is.

 

An old UK government design bulletin has a set of 1:200 scale paper templates for cars and larger vehicles performing complex manoeuvres. Naturally one should account for the regional differences in vehicle proportions. Also, it's unlikely to be as accurate as specialised CAD software for calculating these things dynamically, but perhaps a good start at an early stage of a project.

 

You can find a link to the document here, see page 78 onwards: http://regulations.completepicture.co.uk/pdf/Planning/Design%20Bulletin%2032%20-%20Residential%20Roads%20and%20Footpaths%201992.pdf

 

Design Bulletin 32 Residential Roads and Footpaths, 2nd Ed. 1992, HMSO

 

If it's crucial it would be an idea to use proper software to do the calculations, or let the client know that they should appoint a consultant to undertake the swept path analysis!

[Tyke]

Hi,

 

This is an old post now but I have been looking for info on vehicle turning circles and more complex manoeuvres. It's a lot more complex than I'd imagined! It would seem people used to use templates (due to the complexity of the calculations and specific vehicle characteristics involved). More recently people use dynamic software. There are also consultancies who undertake Swept Path Analysis, so that really shows how complex the subject is.

 

An old UK government design bulletin has a set of 1:200 scale paper templates for cars and larger vehicles performing complex manoeuvres. Naturally one should account for the regional differences in vehicle proportions. Also, it's unlikely to be as accurate as specialised CAD software for calculating these things dynamically, but perhaps a good start at an early stage of a project.

 

You can find a link to the document here, see page 78 onwards: http://regulations.completepicture.co.uk/pdf/Planning/Design%20Bulletin%2032%20-%20Residential%20Roads%20and%20Footpaths%201992.pdf

 

Design Bulletin 32 Residential Roads and Footpaths, 2nd Ed. 1992, HMSO

 

If it's crucial it would be an idea to use proper software to do the calculations, or let the client know that they should appoint a consultant to undertake the swept path analysis!

 

As ReMark said above use the free CadTools, here's the link: http://www.glamsen.se/CadTools.htm.

 

We have used it for very many years on DB32 designs and never had any problems getting the Highway Autorities' approvals. I don't think that there is any need to go to consultants at this level. The results from CadTools are much better than the diagrams in DB32. With CadTools you can create customised vehicles, such as articulated buses, rather than trying to get one of the DB32 vehicle configurations to fit your specific case.

 

Ben

Edited April 19, 2017 by Tyke

[BIGAL]

We are currently looking at "Triples" & "Road Trains" for the docks, there is no way you can check their path with a template. For any one interested length = prime mover plus 3x19m semis. Weight 60+Tonnes. You close your eyes when the 3 semis of fuel go past. Watching them start is amazing 1st gear around 300mm travelled before pulling 2nd. Google road trains australia