CERTIFYING AN ELECTRONICALLY-MEASURED COURSE
Today a certifier asked me if I’d be willing to take on the data review for a measurer who wants to use electronic measurement. He felt he was not up to the job. I reluctantly agreed. I say “reluctantly” because I have done this once before, and found the process to take an inordinate amount of time, and does not lead to complete confidence.
Electronic measurement has one undeniable advantage – the counting device is cheaper.
There are many disadvantages, at least for a reviewer/certifier. When a Jones counter is used, there is no question that the counts accurately reflect the revolutions made by the wheel. With electronic counting, several things can happen that will make the count come out wrong.
1) Was the counter properly zeroed? Some cyclocomputers require that an extra pass of the magnet be made to get the device properly zeroed. Some do not. Since one revolution is about two meters, this is not a trivial error.
2) If the bike is stopped with the magnet near the sensor, a slight movement can cause an extra revolution to be recorded.
3) Was the cyclocomputer properly calibrated?
When I have used the electronic counter I have always satisfied myself that I got things right. Did I? I’m a final signatory and nobody checked my work. How do I assure myself that data I get from a measurer has not been polluted by mistakes in the setup and/or use of the cyclocomputer? For me to do an honest job of certifying I need to have a pretty high degree of confidence that the measurer set up and operated the counter correctly.
I don’t welcome all the questions I need to ask, and the time it takes, to pry out the correct answers from the measurer. At the end I lack confidence in the result.
I don’t know what sort of skill level I’m going to get from this measurer, and I know I’ll have lots of questions.
So – Can anyone suggest the sort of questions that must be asked and answered by a certifier? I am doing it by the seat of my pants, and I don’t like it. At present we do not have a uniform, commonly-accepted procedure for submitting cyclocomputer-generated data to a certifier.
Neville Wood has provided a fine body of work describing how the cyclocomputer can be used, and he himself uses the method.
What is needed now is a clear set of guidelines for certifiers to use in evaluating electronically-generated data.
I’m on the verge of refusing to handle any more electronically measured courses until the uncertainties in setup and use are cleared up.
You have the same concerns that I have had with people asking me about using an electronic counter. As you have stated there are a lot of places for one to go wrong with this device.
I find most have asked me if they can use this device are doing it because of cost. Is this a good reason?
As for reviewing one's work, maybe the RRTC could designate one person to take all applications for certification with an electronic couner. Neville would be a good choice, but maybe there are others.
As for the uncertainties, is it time to suspend accepting applications with the electronic counter? One reason the RRTC approved the use of an electronic counter was the Jones Counter was no longer in production. Now we have the JR Counter and all is well.
Neville has done a wonderful job developing the electronic counter, however I agree with Pete's concerns.
Anyone who doesn't own a Jones counter is probably, and in fact almost by definition, an inexperienced measurer. Those are exactly the people you don't want trying to measure a course for certification with an electronic counter, no?
Why not just require them to have a Jones/JR counter on their bike as well as the electronic one, and tell you the count at the start of the ride and the count at the finish. That's the only time they would ever have to pay attention to the Jones/JR counter, so they would still be able to take advantage of the benefits of using an electronic counter.
But maybe this would limit taking full advantge of going electronic. I don't know.
Why don't we just put this to bed?
We gave electronic measurement a serious look mostly because there was a legitimate concern that our supply of mechanical counters would dry up, and we would have to find another device to count revolutions. We now have the Jones Counter model JR, and that concern no longer exists.
As Pete has previously made clear in his posts, the electronic methods may work, but they are extremely hard to get right. As Mark points out, anybody who is an experienced measurer already has or has access to a mechanical counter. Thus the people using the less reliable method are those who are less experienced at the craft of course measurement.
I can't speak for other certifiers, but I have three extra mechanical counters I am more than willing to loan to novice measurers who want to take a stab at measuring their own courses. Based on my own experiences with electronic measurement, I would not even CONSIDER trying to walk them through the procedure required to even TRY to get an electronic measurement right.
If someone has mastered the art of electronic measurement, fine. Accept their work. Otherwise, the mechanical counter is the way to do this. Period.
I must disagree with all calling for the elimination of electronic counters. I use one for all of my courses. I also have a Jones mounted most of the time, so I do have a backup, and an overall count. But, as Mark says, I don't look at it during the ride.
I use the electronic counter because it is mounted on my handlebar, where I can easily see it. Also, it only changes once each revolution, so it is easy to slow down at the appropriate location. I also like being able to zero it at the beginning of my course, so my paperwork can be done before I leave my car. By the way, it is not a cyclometer, but a Veeder-Root that cost as much as a JR, and took time to wire. Not for the beginner to use.
Another advantage is that I can throw a switch, and the counter will decrement as I ride back to a missed mile point. Unlike the Jones, which must be rolled backwards. (When doing this, though, it will mess up my JR reading for the overall length.)
I must be aware of the magnet stopping at the sensor, so my zero point on my rim is marked with red tape, not yellow. I have not had that problem since I became aware of it.
My point is, if an experienced measurer wants to go electronic, they should be able to. I would, however, side with all in saying that a beginner should not be allowed to go electronic. The JR allows one to see, and correct, their mistakes. The electronic errors are not as noticeable to a beginner.
My paperwork is no different than someone who turns in a JR application. I have ridden the course at least twice, and the second ride has very little chance of the zero-point stop. As I am just stopping and writing the counter reading, if I had an error on my first ride, it will show very obviously on my second ride. Issue overcome. The number of clicks on the app is immaterial, as long as all the math works properly.
If a certifier doesn't have confidence in the measurer for an electronic count, I don't see why a JR measurement would be much different. They can still make errors with a JR.
I’m with Duane, I think. I use an electronic counter to locate approximately where I should stop, and use the JR counter to record the data where the split is.
Instead of zeroing my JR counter I use Google Earth to figure out how far I have to go from the calibration course to where I’ll start to measure. I may have to rotate my wheel a bit to get the proper starting count, but I don’t find this a burden, because once I have it all my stops are figured for me using my precal constant. I make up a preprinted list of splits which tells me how many revolutions to the next stop, and what the JR count should be when I get there. I record the JR count at each stop, and use the electronic counter only as a guide.
So, at the end of the day I may have done a lot of electronic fiddling, but all of my actual final data is in counts recorded from the JR counter. I can make all sorts of mistakes with the electronic counter, but that has no effect on the final data I record.
I find that on those electronic measurements I’ve reviewed, 90 percent of the review work is spent on trying to determine whether the measurer set up his equipment correctly, and there is no way to tell from the data whether this was actually done properly.
It never crossed my mind that the use of electronic counting should be prohibited. It's too useful to do that. But at the end of the day I see actual counts as being the only truly reliable data that I can use or review.
An odd paradox here. The "simplest" and most "checkable" method (JO) is also the most expensive, which I've found is the reason most people don't measure their own courses. OTOH, the $15 or so for a cyclometer, which can also be used for its intended purpose later, is no deterrent at all, but is more complex to set up & use.
I'm not so sure having a price deterrent (or some other type of deterrent) is such a bad thing. Being willing to plunk down $120 for a JR (I still prefer countin' thingel) probably means the person is serious and committed to the measuring thing, and in getting it right. Ending up with a large percentage of certified courses measured by one-time-only folks would probably lead to more mistakes and more failed validations, which would reduce the general public's confidence in the whole measuring process.
Mark, that's probably true, yet many prolific measurers began their careers as "one-off" people - I know I did. Once they get into it they are more likely to feel the expense of a JO/JR counter more worthwhile.
There seems to be some confusion in this discussion. We are trying to discuss measuring and certifying as if they are the same thing. They are not.
I once had to validate a course in New Orleans. In Atlanta, enroute, I discovered that I had forgot to bring my Jones counter. What could I do? Best I could think of was to put a piece of adhesive tape around the tire and count how many times it went around. I knew this would be very tricky, but figured I could do it.
Fortunately for me I was able to borrow the only Jones counter in New Orleans. I got the validation properly done without incident.
Now picture this. As a final signatory I COULD have tried to count revolutions, and with great care I think I could have got it right. Satisfied, I could sign off. However, what if Joe or Jane Newbie sent me data based on watching the wheel go around and counting revolutions? If they did everything right the measurement would be valid. But how on earth would I get confidence that they got things right? What sort of data would be needed?
I know, from doing several electronic measurements, that it is easy to forget to do things enroute, and that these omissions can cost a loss of accuracy. The omissions leave no obvious tracks to show that anything went wrong.
I would be reluctant to certify based on “I used the electronic method and did everything right. My first measurement yielded 10,000.00 meters and the second yielded 10002.3 meters. Please certify the course.”
So far the advocates for electronic measurement are all experienced final signatories who have never had to convince anyone else that they set up and used the electronic counter correctly. It’s convincing someone else that is the toughest part.
I have had a series of emails from Neville, who feels most can use the electronic counter without any problems. Maybe the solution is to allow Neville to be the FS for all electronic submissions(as he suggested, see below in his email) or only allow experienced measurer’s to use an electronic device. Neville feels confident that with Google Earth he can check their number with reasonable accuracy.
Here is Neville’s email(with some editing):
From: NEVILLE WOOD [mailto:firstname.lastname@example.org]
Sent: Thursday, June 04, 2009 12:21 PM
To: Gene Newman
Subject: Re: Electronic Counter
I am confident I check their work with my measuring skills on Google Earth.
Recently I told you that after measuring the Raleigh Rocks Half marathon, I measured on high-resolution images of Google Earth and came within 0.004% of my bicycle measurement.
Now I find that measurement on low resolution gives similar results. Recently, I measured a particularly complex combined 5 and 10-km courses at Mebane in which I endeavored to get both starts and finishes at the same point with no-turns. Only low resolution were available, but I did the preplanning anyway and was astonished that the courses came out exactly as predicted.
I believe an average person ought to be able to carry out an electronic measurement by just reading a description of the procedures. Also, I do not think the certifier requires any special talent. However, if measurer and certifier are unsure of themselves, I would be agreeable to process the certificate. Without being immodest, I think I am the best person to do this. Regards, Nev
Checking someone's map with Google Earth isn't good enough. Also necessary is a credible set of original measurement data. Otherwise, why measure at all? Just use Google Earth.
I've had good results with Google Earth too, and also some pretty poor results. Remember, the images may not reflect present reality.
If Neville is to become the electronic certifier, it must not be a secret star-chamber proceeding. The methodology he uses to determine the reliability of the submitted data must not be some secret formula, or some intuitive thing. It should rest on real, reliable data, the quality of which should be credible.
I believe that if we are to accept electronic measurements, the review process should be shared with any curious measurer. Anointing Neville as an all-knowing guru of electronic measurement should be done with care, and the procedure used for review should be publicly available.
As far as I know, Neville has never acted as a certifier who reviews the work of others. I have reviewed two measurements done electronically, and in neither case did the measurer get it right the first time.
Perhaps I'm being unduly skeptical. Other opinions are sought.
I have a sense that the proposal to make Neville the Electronic Czar may be done in an effort to make the pesky problem go away.
A credible review process is needed, and at present it does not exist. Perhaps, in the process of reviewing some actual measurements done by others, Neville will be able to produce such documentation so that all certifiers can do the electronic job.
How is reviewing electronic data different than reviewing JR counter data? Each is a submission of reported readings.
The obvious potential for error in the electronic count is to have the sensor and magnet aligned while stopped, giving additional clicks. But, if two measurements are done of the course, it should be apparent if more than one additional click occurred. Then, there would be another measurement required, until two measurements yielded comparable results.
With a Jones, if someone over-shoots a location, they must back up, or ride back to a known point, then continue, after making notes of the change in clicks (if they didn't roll the bike back to a point). Even if they rolled the bike backwards, are you confident they did the SPR, with the same wobble-factor as on the forward ride? How can we assume it was done correctly?
The bottom line is that either method can have inaccurate measurements fudged to make it look good to the certifier. We have to take someone's word for it that the proper processes were followed. Why is the method of measurement a factor in this trust?
I much prefer the electronic method, as I can see the counter much easier as I ride. I am aware of the potential for error, and keep it in mind. My paperwork is no different than a measurement done with a Jones, other than I have fewer clicks per mile. And, regarding over-shoots, the electronic (using a reversible VR) is better, as I can flip a switch, and ride back to a known point on the course (the counter decrements), then turn around, flip the switch, and continue my ride, without any change in counts, or having to walk my bike backwards to that known point.
Just sayin', we are trusting the measurer to do the job correctly, no matter which type of counter they use. Paperwork can be fudged with either method, and either method can have pitfalls to overcome. (And, what about the cars parked on the inside of curves? Did the measurer do an offset, or just ride around the car? Just another opportunity to measure correctly, or the easier way.)
Forms have been a part of certification since the very beginning. We presently use forms for the presentation of data from a measurer to a certifier. They are presently based on the use of a Jones Counter.
For electronic measuring to develop widely it will be necessary to produce forms to be filled out by the measurer. Some of our forms will work, some may not.
The Application for Certification of a Road Course would need very little change.
The Bicycle Calibration Data Sheet will require work, so that it will fit the use of electronic measuring
The Course Measurement Data Sheet will require similar rework.
A supplementary data sheet will be needed to describe how the electronic counter is set up. Is the rim marked? Are spokes to be counted? How is proper operation assured?
With a set of forms, tailored to the use of an electronic counter, available, then we will be able to do the job of certifying. It’s how we manage to do our work to a similar standard.
Without a set of standard forms, we will all be using our own personal standards rather than a common standard for all.
Because of all the varieties of electronic counters, and the various ways they record impulses, I suspect the work of developing a common standard will be difficult. But it needs to be done if electronic counting is to become more than a stepchild, which is where it is today.
As I understand it, the only certifier who has ever certified a course measured electronically by someone else is me. Correct me if I am wrong. All present proponents of electronic measurement have not had to submit electronic data to anyone but themselves. All are confident that they get it right.
We have a multiplicity of electronic gizmos out there, each of which has its own peculiarities. Some don’t record a count upon the first passage of the magnet past the sensor. Some do. Some “go to sleep” if the bike remains stationary for a certain period, and lose a count in doing so, unless the measurer takes action. All are subject to problems when the magnet and sensor remain close to one another, possibly generating extra revolutions.
I understand that Duane’s rig goes beyond the common off-the-shelf cyclocomputers, having some extra desirable features.
This lack of commonality poses a large problem for us as certifiers. The measurement analysis is easy compared to establishing that the data is untainted by improper procedures. Must a potential certifier have to be able to deal with any cyclocomputer that comes at him via a measurer? This would be a heavy load indeed.
I have a lot of experience measuring courses with Google Earth, and am a big fan. But there's a couple reasons why it would not be possible to use it to confirm the accuracy (to the level necessary for certification) of a measured course.
1) Turns are often obscured by buildings, trees, or shadows, making it impossible to determine the path of the SPR.
2) Landmarks that were used to locate the start and/or finish line are not visible or easily identified.
There is another aspect of the certification process that is difficult for a certifier to check, and it is a huge source of potential error. That the map submitted does not follow the same course that was measured.
While I'm sure this is a rare occurance, I am aware of two cases where this has happened. Both were discussed at length in the message forums, so they are no secret. While fixing the problem of error-checking electronic counter submissions, I think we should also address this problem.
Pete - I don't understand why the forms would have to change, other than a checkbox or blank, to indicate electronic measurement or JR.
The calibration and calculations are not sufficiently different, as I can tell. When I use my JR, I have whole numbers. When I use my electronic, I extend to 2 decimal places. Both yield a number, which is then compared to other numbers. The process is the same; the only difference is the number format.
I submitted my paperwork to Dave Poppers for a couple years, first with the Jones format, then using the electronic counter. I don't think he had issues with it, as I don't recall any conversations regarding the electronic paperwork. If he is not too busy enjoying himself in his retirement, he can comment (I know he occasionally gets bored enough to check back on the forum occasionally ).
I do agree with knowing which electronic counter is used, and also the confidence and competence of the measurer. Your comment about the cyclometer going to sleep is very valid, and would be cause for concern. The VR that I use does not go to sleep, so I have not had to deal with that. But, once competence has been established, there should be no special considerations for paperwork, that I can see.
As for spurious counts, when someone lays his bike down to make a mark, or nail a washer onto the pavement, there is the possibility of the front tire rotating, which would be of concern with either the JR, or an electronic counter. For that reason, I don't see the electronic counter having much more susceptibility to problems than a JR. It still comes back to the measurer's competence.
The two electronically-measured courses I certified were measured by first-timers, and it was a total bitch getting at what I thought were the facts.
I had zero faith in the measurers' knowledge, because neither had demonstrated any to that point. In addition to not getting their electronics rigged right, they made the normal first-timer mistakes.
It took a lot of time and back-and-forth to finally get things straightened out, and then I had to ask for one more measurement. When we had finally wrapped things up the measurer said he was going to get a JR.
Learning the electronic way is a lot easier for an experienced measurer than for a novice.
Totally agree with you on that one, Pete. I don't recommend it at all for neophytes.
A source of error that has not yet been discussed is zero offset. When the rim is marked, and the wheel mounted, the magnet which trips the cyclocomputer must be affixed to a spoke. After this has been done, I believe it is rare for the cyclocomputer to register a new count when the rim reading is EXACTLY zero. On my bike the rim reads 0.95 rev when the cyclocomputer trips.
When I stop at a point, and the rim reads 0.97, and the cyclocomputer reads 17.72, what is my actual count? Is it 1772.97 or is it 1771.97? Deciphering this requires a mental trick. What makes it worse is that the trick is only needed when the rim reads between 0.95 and zero.
In the course of setting up two cyclocomputers, and marking a wheel, and measuring several courses, I believe I have made most of the mistakes that it is possible to make. I believe I successfully corrected for them, but as the written data does not reveal what I did I will never know.
I don’t believe I am alone in this.
The electronic counter requires constant vigilance. Each stop may require a different action by the measurer. Some measurers will get it right, and some will not. How can the data be presented so that the certifier has confidence that:
1) The equipment was properly mounted and revolution fractions reliably marked on the rim.
2) Zero offset is accounted for.
3) The counter did not “go to sleep” while the bike was stopped.
4) The extra count is added (on cyclocomputers requiring this) so that the first revolution produces a count of “1.”
I haven’t figured out a methodology myself. How can I convince a certifier that my data is reliable?
It’s true that one can, and will, make mistakes when using a conventional JR, but these mistakes don’t relate to the operation of the counter. It works properly or it doesn’t work at all.
I don’t believe electronic counting will be ready for prime time until the question of reliable data presentation is solved, and believe its use as an official tool for the measurement of courses should be discouraged. It is hugely useful as an enroute aid, however, when the “official” counts are those read from a Jones counter.
You are always bringing up how you don't feel electronic counters are reliable in many measurer's hands. You don't feel they (measurers) can necessarily be trusted to use the electronic counter correctly. You have pointed out many of the ways the electronic counters can be incorrect, yet not be detected. Are you a curmudgeon?
Actually, I think you are correct an almost all of your points. While I didn't readily agree with you, your comments have made me think about the issues you raise.
We certify the overall length of courses. Most of the time, intermediate points, while very accurate, are not certified. With that in mind, why not have JR counts furnished for calibration and Start and Finish counts, along with the calculation for the entire length of the course, when using electronic counters? The measurer will also supply electronic calibration numbers, and can note the intermediate counts for the electronic counter. If the JR counts for the overall length are correct, and the electronic counts also check-out, then the course is certifiable.
The intermediate points will be correct, if the overall electronic counts jibe with the JR counts. If the electronic counts don't match-up, the measurer will have to re-do the course, until the electronic counts are consistent with the JR counts.
The math for the JR would only be Start counts plus counts-needed-for-course, equals Finish counts. The electronic counter is zeroed at the Start, so no additional math is required for subsequent measurements.
I think, as a certifier, it would be simple to verify the clicks for the overall for both the JR and electronic, leaving the data review simple, also.
From all of Pete's concerns, and my experience using both JR and electronic, I think the dual-counter requirement for Start and Finish clicks (and calibration) satisfy all of Pete's legitimate concerns, and is not a burden on me, as a measurer. Since we only want experienced measurers to use electronic counters, they will already have a JR. I truly don't think the cost should be considered an impediment, as that is a tool of the trade.
Thoughts from others that use electronic? Pete, would this simplify your review, and alleviate your concerns? It would only require a slight modification to the data sheet, and since many of us use Excel, that is a simple matter.
I believe curmudgeon is not misapplied in my case.
As for your proposal, I agree with you 100 percent. Using the Jones for calibration and overall distance is not a great burden, and frees the measurer to do what he likes for the rest. I'd have no problem with certifying data of this sort. I have one measurer who sends me only overall data, which I don't like but cannot object to. Your proposal would be no worse - it does provide the minimum needed for certification.
Of course, the cost benefit is lost, and with it the incentive to go electronic.
I've been using my electronic rig continuously since Neville originally posted its setup and use, and I think it is a wonderful tool. However, aside from a few trial courses where I attempted to provide a 100 percent data-report using electronics, I have not recorded my electronic data. I record only Jones counts. Anyone wishing to check my data will find familiar units without ambiguity as to reliability.
I do pretty much what Duane does - JR for the overall distance, electronic for intermediate splits. However, if the course is nearby and I am riding to the location, I'll go all-electronic as I can pre-calculate the splits and total distance on a spreadsheet, print it out, then zero out the cyclometer when I get to the start/finish before riding.
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