Course measurement accurate to 0.01 m?


Comments about this discussion:

Started

3.1.1 says that a 400m athletics track should be measured with 0.01 m accuracy.
5.1.1 says that a circuit used for time trials should be measured with 0.01 m accuracy.

For a 400m track this can be very challenging. How far from the inside of the track do you measure? This isn't even specified in 3.1.1.
I once heard that in athletics tracks, this is often 30 cm. Then again, how do you define the inside of the track? In reality, this is not a clear-cut mathematical shape, there will be small-scale irregularities which often will make it impossible to define the exact length, let alone to measure it.

For an arbitrary circuit (as meant in 5.1.1), about the same holds true. However, here (for time trials records) the WRG do require that the inner perimeter is taken. But again, I think 0.01 m is not realistic to require.

Comment

3.1 says "Standard track records are held on a 400m Athletics Track, ..." and I think for 400m Athletics Track we can define the measurement very clearly (In my opinion such a definition would be better in the Ruebook than in the WRG), becuase there is a definition from athletics.
Definition of a standard 400m track according to IAAF (IAAF Competition Rulebook 2018-2019: Rule 160):

1. The length of a standard running track shall be 400m. It shall consist of two parallel straights and two bends whose radii shall be equal. The inside of the track shall be bordered by a kerb of suitable material that should be coloured white, with a height of 50mm to 65mm and a width of 50mm to 250mm. The kerb on the two straights may be omitted and a white line 50mm wide substituted.

2. The measurement shall be taken 0.30m outward from the kerb or, where no kerb exists on a bend, 0.20m from the line marking the inside of the track.

3. The distance of the race shall be measured from the edge of the start line farther from the finish to the edge of the finish line nearer to the start.

4. In all races up to and including 400m, each athlete shall have a separate lane, with a width of 1.22m ± 0.01m, including the lane line on the right, marked by white lines 50mm in width. All lanes shall be of the same nominal width. The inner lane shall be measured as stated in Rule 160.2, but the remaining lanes shall be measured 0.20m from the outer edges of the lines.

This might seem a bit much at first, but we would have a really good definition of our 400m standard track.

At the same time, we could certainly make use of measurement protocols which are often available, especially in Europe, and which confirm compliance with the IAAF rules, so that we have a confirmed measurement of the courses.

Comment

I'm surprised that in the IAAF Rulebook, the radii and the lengths of the parallel straight are not prescribed. Elsewhere, e.g. here or here, I found that the track comprises 2 semicircles, each with a radius of 36.50m, which are joined by two straights, each 84.39m in length.If it were for the IAAF Rulebook only, the radii could be much smaller or bigger.

Then again, here is in print that according to IAAF, the distance is not measured along the shortest possible route but 20 or 30 cm away from the inside (depending if it's raised or not). This means that this rule is part of our track records. But our records on any other circuit than an athletics track prescribe shortest possible route (i.e. 0 cm from the inside). I don't like that difference.

I think that if a track is certified/verified according to IAAF requirements, it should be OK for unicycling without requiring further measurement or details thereof - we only need proof that the track is indeed certified. I agree that these issues are best regulated in the IUF Rulebook, not in the WRG.

I maintain that 1 cm accuracy for the length of an athletics track, or any circuit of similar or larger size for that matter, is very challenging. You are right that the length of an athletics track is very precisely defined. But the actual physical track dimension may not have that same precision. For athletics tracks, this is a moot point if we rely on IAAF-certification. Requiring such a high accuracy is still an issue for any other track.

Comment

The radii and the lengths of the parallel straight of a 400m track are in fact not exactly fixed and can therefore vary within certain limits. The exact limits for the different types of stadiums can be found in the IAAF Track and Field Facilities Manual.

Exactly, the length of a 400m track is measured 30cm or 20cm from the inner lane boundary. The shortest possibe route (SPR) in athletics is also determined with a distance of 30cm to the inner edge of the running track.
"Measuring the SPR means hugging the inside edges of bends. The path you should attempt to measure officially lies 30cm from the kerb or other solid boundaries to the running surface. [...]"
So there is no difference in athletics here! I consider this to be quite reasonable.

Athletics tracks will not be accurate to 1cm either. The width of the lanes is fixed at 1.22m ± 0.01m, but the length of the 100m may be 100m+0.02m and of the 400m even 400m+0.04m.
Of course it will be difficult to measure a track without an IAAF certificate with sufficient accuracy, but I think it is the only way to make sure that the time done on such a track is actually comparable to the results and the WR.

Comment

My point for starting this discussion was that 0.01 m accuracy is not really possible, and in practice we do not adhere to it.

I think we must loosen our requirement for this. We can demand the same accuracy (and definitions, such as SPR) as is required for IAAF. For tracks that are IAAF-certified, this will be OK by definition. For non-IAAF-certified tracks, it has to be done at the request of the organiser (of the competition or the rider attempting the record).

If we agree about this principle, the next question is: do we refer to IAAF, or do we 'copy' the current IAAF rules into ours?

Comment

I have given this subject more thought since I last posted. And I want to broaden it from the 0.01 m accuracy issue to all aspects of course distance definition and measurement, in all three categories of records (track, road and time trials).

In the current WR Guidelines, sections 3.1.1, 4.1.1 and 5.1.1 give our requirements for course measurements for Track, Road and Time Trials, respectively.
As they are defined now, they have some significant issues.

For Track, the current WRG require evidence of the exact track measurements, to the closest 0.01 m. To my knowledge, this is a requirement that we never check in practice. Moreover, I doubt that accuracy of the track length of 0.01 m is meaningful or even possible.
I think it would be better to require what IAAF/World Athletics also requires. I found a list of requirements in the World Athletics Track and Field Facilities Manual 2019 edition. (World Athletics was formerly known as IAAF.) One of the requirements is that the track is between 400.00 m and 400.04 m long. This is measured 30 cm away from the inner perimeter (if there is a continuous raised border of certain dimensions).
It seems to me that we should drop our current requirement
"Please supply evidence of the exact track measurements used to the closest 0.01m."
and replace it by
"Please supply evidence that the athletics track where a record was performed, conforms to the World Athletics specifications."

For Road, the current WRG require that the measurement must be accurate to the closest 1 m. Also here, I doubt that this level of accuracy is useful or feasible. At the same time, the WRG state that the course should me measured in a way as accepted by the IAAF. There is a conflict here, because IAAF require a course to be not shorter than the nominal length, and not longer than 1.001 times the nominal length (source: IAAF Measurement of Road Race Courses, update 2008 - I think it is the most recent). E.g. for a marathon, for IAAF the course should be between 42.195 km and about 42.237 km. IAAF also defines Shortest Possible Route as 30 cm away from the inside of every corner or bend - we also use the phrase Shortest Possible Route, but without defining how far it should be from the inside of curves. I think we should have the same rules as IAAF.

For Time Trials, our current requirement includes:
The course must be a circuit, with distance taken from the inner perimeter of the track, accurate to 0.01m. A report from
a registered surveyor is required as evidence of circuit size.
"Distance taken from the inner perimeter" is problematic on several levels.
(1) It seems to prescribe that the measurement must be done at zero cm from the inner perimeter. In practice, it is not possible to measure there with a Jones Counter bike, nor is it possible to unicycle there.
(2) If a circuit has left and right bends, one should not hug one side (either left or right) of the track all the time (the inner perimeter), but rather hug the inside of each individual bend, connecting those with straight sections.
(3) Accuracy to 0.01 m is simply not possible, nor needed, for circuits of any practical length.
Our phrase "registered surveyor" is not clearly defined. IAAF and AIMS (Association of International Marathons and Distance Races) have a grading system to approved measurers, and for world records they require an A or B grade measurer. It we copy this, it seems a lot better defined than "registered surveyor".

My suggested changes unify the course length requirements for our three types of records, remove some unclarities and "impossibilities", and establish better correspondence between the IUF rules and what other sports are using.

Comment

That's what we (Scott, you and I) have been discussing while waiting for Jana's measuring documents - I have nothing to add and agree Klaas.

What do you want to do ?
New mailCopTh

Comment

I agree with unifing the course length requirements for the three types of records and establishing a better correspondence between the IUF rules and what other sports are using. So I basically agree with Klaas as well.

But I would like to point out that I think I have always understood our current wording ("exact track measurements used to the closest 0.01m", "accurate to 0.01m") somewhat differently from what the rest have done?! I did not understand it that way, a track e.g. must be exact 400.00 m long, but the measurement must be exact enough to distinguish whether it is 399.99 m or just 400.03 m long - for that, the measurement must of course be exact to 0.01 m. But only the measurement, not the track itself - so for me our previous requirement was not a contradiction to what the IAAF demanded (because to check the compliance with the requirements of the IAAF a measurement to the closest 0.01 m will be still necessary).

Comment

Jan, I see your point. Indeed I think I misinterpreted what the 0.01 m accuracy refers to. It does indeed not refer to the length of the track itself, and it makes sense that it refers to the measurement accuracy with which to measure the track length.

I understand from the Track and Field Facilities Manual 2019 Edition, that they don't prescribe to measure the length of the track directly. Rather, they determine the radius of the bends and the lengths of the two straight and then calculate the length.

I would propose that we require what IAAF/World Athletics also require.

For me it would be good enough if we know that an athletics track (that a track record has been performed on) is guaranteed to conform to the specs of IAAF/WA. Then we can in the WR Guidelines just refer to the IAAF/WA requirements. I realise that in this way, we make ourselves dependent on them. If they change their requirements, ours would change automatically. But we don't really have a choice, because we can't have an athletics track constructed for unicycling with our own specs. We have to use existing athletics tracks. Fortunately, the IAAF/WA specs will be quite stable, because the whole athletics world depends on them.

Comment

In the last year I have been involved in two world record accreditation teams for an indoor and outdoor cycling events at velodromes. Both velodromes were already certificated. Guinness insisted on checking the distances. The indoor one was surveyed by two professional surveyors using a Tellurometer that they deduced the length as Klaas describes. For the outdoor velodrome we were given 2 counter measuring wheels, one which had been recently certified. We had 3 people test the track, twice each. The track measurements varied by almost 1/2m.  The average was within 10cm over the 450m.  We concluded that we would need to reply on the original certification for the track.

Having seen how hard it was to get a consistent measurement the measuring wheel, a calculated method is preferred. 

I agree with Klass, we should accept track is certified that conforms to IAAF/AW standards or should be surveyed to their standards.

Comment

I think we all agree on this topic, or do we have still open points that we need to discuss?

Comment

I have prepared a proposal offline, and justed started to type into the official template the title "Course measurement for all types of records". However, it suddenly occurred to me that we haven't said anything about the measurement of 30m wheelwalk, 50m one-foot or the slalom. These do fall under Chapter 3, and thus under this Discussion/Proposal. So I think we need to include these - do you agree?

These distances are usually measured with a tape measure, I think. Since they rely on non-permanent markers, it doesn't seem practical to require a professional surveyor to do this. If you agree, then my next question is: should we prescribe more requirements, like temperature compensation, a defined pulling force, number of measurements etc?

Comment

You are of course absolutely right that we also have to think about these disciplines, for which there are no markings on standard athletics tracks. In Germany there is a 50m marker on many tracks, but we cannot assume that it exists on every athletics track, and since it is not an official IAAF marking, its exact position might not be measured for IAAF certification. For the start line of 30m wheel walk (and also the 10m) you can use the athletics markings of the hurdles and the relay handover zone of the 4x400m relay as an orientation, there should be markings at 30m and 10m. Nevertheless we should say something about measurement here, since there are of course no real start lines on an athletics track.

I have the feeling that I have already written something on this subject somewhere - with regard to the accuracy of measuring tapes and possible requirements for them. But I can't remember if it was somewhere here or in the last rulebook committee.

What Word Athletics writes in the Rules (Rule 148):
"[...] all measurements shall be made with a calibrated steeltape or bar or with a scientific measuring device. The steel tape, bar or scientific measuring device shall be manufactured and calibrated according to international standards. The accuracy of the measuringequipment used in the competition shall have been verified by anappropriate organisation accredited by the national measurementauthority. [...]"

I think distances up to 50m - and that's what this is all about - should be measurable with a steeltape and it should be no problem to use steeltapes that guarantee an appropriate accuracy (this is basically what the World Athletics rules require). Maybe we can add that the measurement has to be carried out and documented by three judges and I think we are in a good position then. Pulling force should not be important with steeltapes no Judge will pull it - I hope :D and the temperature deviation is usually positive, so we should measure only too long, but this is not critical and is taken into account in the accuracy of the tape measure.

 

 

Comment

I agree with you, Jan.

What do you want to do ?
New mailCopI ag

Comment

Klass, you had written that you had prepared a proposal - would you post it here? In any case, I think the next Rulebook update should include some additions to the track part regarding the venue, especially for Unicons. This would hopefully ensure that a Unicon meets all requirements for WR.

I would suggest something in the following form:


X.X Venue

1. Every track and field competition venue approved for athletics is approved for official unicycle competitions.

The essential criteria that such a venue must comply with are the following:
2. Any firm, uniform surface that complies with the specifications for Athletics competition venues is permitted.

3. The length of a standard competition track shall be 400m. It shall consist of two parallel straights and two bends whose radii shall be equal. The inside of the track shall be bordered by a kerb of suitable material that should be coloured white, with a height of 50mm to 65mm and a width of 50mm to 250mm. The kerb on the two straights may be omitted and a white line 50mm wide substituted.

4. The measurement shall be taken 0.30m outward from the kerb or, where no kerb exists on a bend, 0.20m from the line marking the inside of the track.

5. The distance of the race shall be measured from the edge of the start line farther from the finish to the edge of the finish line nearer to the start.

6. In all races up to and including 400m, each athlete shall have a separate lane, with a width of 1.22m ± 0.01m, including the lane line on the right, marked by white lines 50mm in width. All lanes shall be of the same nominal width. The inner lane shall be measured as stated in pragraph 4., but the remaining lanes shall be measured 0.20m from the outer edges of the lines.

Comment

Point 1 and 2.

Do we want/allow racing on natural grass? The World Athletics Association has a section about natural grass in their Track and Field facilities manual. My school had an athletics track that was approved by the head teacher for athletics... I suspect it was not to our standards, I guess we should stipulate who standards it is approved to.

Maybe:

1. Every track and field competition venue approved for athletics to IAAF/AW standards may be approved for official unicycle competitions.

2. Any firm, uniform surface that also complies with the specifications for Athletics competition venues is permitted.

Comment

@ Roger: I was actually not aware that the IAAF/WA allows other surfaces than synthetic ones for competition tracks. The Track and Field Manual (2008) that I have in front of me only contains the section on synthetic surfaces - but when I reread it agin, I saw that it indeed does contain a reference to information about other surfaces. (Information on unbound mineral surfaces and natural grass surfaces, not now included in this manual, is now available on request from the IAAF Office.)

With my very general statement, I wanted to avoid that all tracks have to be approved by us. Perhaps the synthetic surfaces can be integrated and thus we are on the safe side? I think we all agree that only synthetic surfaces are reasonable for unicycle competitions - especially for world records. The IAAF/WA will also only recognize performances on synthetic surfaces as WR I think.

 

Proposal for 2:

2. Any firm, uniform surface that complies with the specifications for syntetic surfaces for athletic competition venues is permitted.

Comment

Yes, that should cover it simply.

Comment

Are there any further comments or objections to the proposal? If not, I would like to create a proposal that can be voted on after the official review time.

Comment

This discussion is not only about track courses, but also about road race and time trial courses. In the current WRG these have some discrepancies.

Your draft text posted above as "I would suggest..." is only about track racing, and moreover it is IMHO too detailed. I think it is sufficient, for track racing, to refer to the IAAF/AW regulations, and state that any track that is approved to those standards, is OK for unicycling World Records. I don't think we need to bother about venues that are not approved according to IAAF/WA, and that we approve it ourselves by all the detail that IAAF/AW prescribe. I might be wrong, but I think we won't encounter 'good' tracks that are not approved yet. And even if such tracks would be used for a unicycling WR, it is sufficient for the WRG to refer to the IAAF/WA regulations rather than trying to repeat them.

Yes, I have a proposal ready for this discussion, except that I need to incorporate something about track competitions that don't rely on track markings (such as IUF slalom). I will share it here after at least one response on my remarks above.

Comment

Oh yes of course, my proposal referred only to the track races... for the road races and the time trial records, of course, we also need appropriate specifications.

The reason why I would like to have the specifications in our rulebook in such detail (actually not in the WRG, but there we have again the problem with the transitional solution) is that it is much easier for organizers if they find everything they need to know in our rulebook and do not have to search the IAAF/WA rulebook. That is very long and surely leads to the fact that many organizers (of smaller competitions) do not even look for the corresponding specifications. With the proposal above, only the surface would be something that is not fully described in our own Regelwek, which I would very much welcome. In addition, we would keep the dependence on the IAAF/WA rulebook very small, which protects us from unnoticed changes.

Comment

Here again, we need to address the issue of external rules first, see Discussion 37.

For information (this is not a proposal yet!), this is the text I had in mind for a proposal from this discussion (I mean #27), but it is dependent on how we handle our dependence on external rules:

Proposal based on Discussion 27
Title: Course measurement for all types of records
Summary: This proposal rewrites and unifies the course length requirements for all types of records
Background: In the old rules, there are unjustifiable differences between the requirements for Track, Road and Time Trials records. Also there are some unclarities or ambiguities, e.g. around "registered surveyor", Shortest Possible Path (how far from inner perimeter) or what the stated accuracy actually refers to (the track length compared to the nominal length, or the accuracy of the track measurement regardless of how long the track is). In addition, the new text solves some inconsistencies, such as allowing a methode as accepted by the IAAF while at the same time setting requirements that go against the IAAF protocol. Finally, the new rules are more conform to what other sports are doing.
Old Rule
3.1.1 Course measurement for standard track records
Standard track records are set on a 400m athletics track. Please supply evidence of the exact track measurements used to the closest 0.01m. This should be either a surveyors report, or a letter from the sports body in charge of the facility stating the size of the track and how this was determined.
4.1.1 Course measurement for road racing records
The measurement must be accurate to the closest 1m. The course should be measured by an independent referee using the calibrated bicycle method with Jones Counter as accepted by the IAAF (International Association of Athletics
Federations). The course should be measured twice along the shortest possible route, with the lower of the two measurements used as the official distance.
Other measuring methods may be used, but must be equivalent in accuracy to the above method. If in doubt, approval should be sought from the IUF prior to an attempt.
5.1.1 Course measurement for time trial records
The course must be a circuit, with distance taken from the inner perimeter of the track, accurate to 0.01m. A report from a registered surveyor is required as evidence of circuit size.
If the track is a bicycle velodrome, or 400m athletics track (as used for standard track records) , evidence of the track size should be submitted according to Section 3.1.1.
New Rule
3.1.1 Course measurement for standard track records
Standard track records must be set on a 400m athletics track, with the exception of 30m wheelwalk, 50m one-foot and IUF slalom. Records in the latter three disciplines may be set on any area, outdoors or indoors, that has a comparable riding surface to a regular outdoor athletics track.
Records that rely on the dimensions or lines of the track must be set on a track that is certified conforming to IAAF/AW standards, or has been surveyed to their standards. (IAAF = International Association of Athletics Federations; AW = Athletics World, i.e. the successor of IAAF.)
For 30m wheelwalk, 50m one-foot and IUF slalom, the lengths and dimensions should be laid out as accurately as possible. Use of a commercially available metal tape ruler is accepted.
4.1.1 Course measurement for road racing records
The course should be measured conforming to the standards of the IAAF/AIMS for world records, by a Grade A or B surveyor as defined by IAAF/AIMS. (IAAF = International Association of Athletics Federations; AIMS = Association of International Marathons and Distance Races.)
5.1.1 Course measurement for time trial records
If the record is set on a 400m athletics track, its length must be assessed according to 3.1.1.
If the record is set on any other circuit, its length must be measured according to 4.1.1.

Comment

In principle, I like your suggestion, but I think we should refer to my "Venue" suggestion for the standard track records. For this we could include it temporarily in the WRG and integrate it later in the Rulebook. However, in the Venue section we would need to add a paragraph about the IUF Slalom, 30m Wheel Walk and 50m One Foot, as these can also be held in an indoor athletics facility, for example.

For measuring distances in Slalom, Wheel Walk and One Foot, I would prescribe the accuracy class of the measuring equipment. For example what Word Athletics writes in the Rules (Rule 148):
"[...] all measurements shall be made with a calibrated steeltape or bar or with a scientific measuring device. The steel tape, bar or scientific measuring device shall be manufactured and calibrated according to international standards. The accuracy of the measuringequipment used in the competition shall have been verified by anappropriate organisation accredited by the national measurementauthority. [...]"

 

Comment

Do you want to 'refer' to your Venue suggestion, or rather incorporate that whole section in my text (so long as the Rulebook doesn't have this text?

As to specific requirements to length measuring devices:
Your first suggested sentence (from WA Rule 148) doesn't say much. Every measuring tape will be calibrated in some way.
The second sentence raises the question: what international standards? I checked a few tapes I have, and they have various codes on them that might refer to international calibration standards.
The third sentence seems over the top. Does my measuring tape (my specific copy) have to be inspected and verified by an appropriate organisation before I can use it for e.g. IUF Slalom?

What magnitude of inaccuracy do you expect from commercially available steel tape anyway?
I checked two of my measuring tapes against each other. One brandless and with no (calibration?) codes, the other from Fisco and with some codes that might refer to accuracy class or calibration. At 3 m length (the max of one of them) the difference is about 0.1 mm. Now n=2 is a very small sample. Still, you can't even set up a slalom course with such accuracy, the cones are not precisely enough defined for it. Similarly for lines on an athletics track for ww or onefoot, or for 10 m slow. And less than 0.01% won't be significant in the achieved times either.

For now, I maintain that any commercially available steel tape would be acceptable. Let's not make things overly complicated.

Comment

I would add the venue proposal as a separate paragraph in the WRG as long as there is no corresponding paragraph in the Rulebook. If the rulebook is updated, the paragraph can be exchanged for a reference to the rulebook.

Regarding your comments on calibrated measuring devices:

1. I think there are also measuring devices that are not calibrated in any way - these are generally excluded by the first sentence. There may be only a very very few of them, but I think it is an important task of the WRG to exclude such devices.Otherwise, we would be leading our own rules ad absurdum if we demand a certain accuracy in the measurements but do not make any specifications for the measuring instruments.
2. I think we had a similar discussion with the wind measurement. In the end, it doesn't matter to which standard the device is manufactored and calibrated (there are different standards for different devices, which we can't list here) - what matters is that it is manufactored and calibrated according to a standard and thus it would be possible to check which limits and accuracies that must be maintained.
3. In interpreting the sentence, I would not go so far as to say that the individual specific tape measure used at the competition must be appropriately examined, but that a "type examination" is sufficient. If such a "type examination" is available, we can be fairly sure that the corresponding devices also comply with the accuracies required in the standards.

 

Depending on the accuracy class (1, 2 or 3), the deviations may be a maximum of 5.1 to 20.6 mm, e.g. at 50m. I'm sure that you will find measuring tapes without certifivation, wich have a much higher inaccuracy. 


Copyright ©

International Unicycling Federation