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15 replies

4 tips/gadgets for elderly measurers

M mikesandfordMember
Here are my tips. What are yours?

1. Electrically assisted bicycle - choose one with a 250 watt motor driving the crank or rear wheel, not the front wheel which would upset the measurement readings. If instead of a hand controlled throttle, it has a torque sensor to measure the pedal effort and adjust the motor power in proportion, you will find it rides exactly like a pedal bicycle except hills, headwinds etc will become easy to ride without effort or wobble. It also helps with endurance - a marathon becomes as easy as it was years ago! Link

2. Laser distance meter - to layout calibration courses without having to scrabble around on the ground every 50 metres at the end of a steel tape. I am using the Bosch GLM250VF which has a maximum range of 250 metres. It is mounted on an equatorial telescope mount. Link
Longer calibration courses up to 500m can be measured by placing plastic retro-reflectors at both of the end nails and using the laser measure from near the centre point to the endpoints. See Mark Neal's report.

My latest use of my GLM250VF on last Saturday was to confirm a 249.775m calibration course which I had set out on a pavement in Llandudno last April. A ladies world best 24 hour distance of 247.076 km had been set, and I was engaged on a validation measurement of the distance. The average cal course length from 4 laser readings gave 249.776m, which was a rather fortuitously close agreement since Class II steel tapes have a maximum error of 0.02% ie 50mm, and the Bosch Laser with a good signal from a retro reflector has a stated maximum error of 0.005% i.e. 12.5mm.

3. For a person who finds it tiring to be repeatedly, bending/kneeling to mark the road, we need gadgets to insert PK nails from a standing position, and also to paint/chalk the road while in a standing position. I have yet to look for aids to achieve this. It is important - last week, while chalking the 6.33 metre turning radius at the ends of the Llandudno 1.0276 km course, I had a bystander come over and ask if I was OK; he had been concerned to see me repeatedly getting to my hands and knees and then struggling up again. This has happened to me at least twice before. I think it is giving me a message that at my age and with my worsening agility, I should no longer be going on my knees in public places.

4. Handle bar readout of counts - my eyesight is still good enough to read the counter on the front axle, but I have made reading mistakes - particularly at night. In the past there was the cable extension available for the JO counter produced by Laurent Lacroix, however he stopped producing these in 2007 when he had difficulty with the supply of parts. Link

In 2008 Tom Riegel worked on modifying the JR counter for handlebar display - but the conclusion in 2009 was that production manufacture was not viable. Link

More recently there was some interesting work by Bob Wemer, Mike Coyne, and Ken Hardwick on use of cameras to display the reading of an axle mounted Jones counter. Link

Neville and others have advocated the use of electronic counters of the type triggered by one or more magnets attached to the front wheel spokes. As described by Neville in numerous posts on this forum, these counters can be successfully used to give a handlebar display, and also simplify some aspects of the measurement procedures. However, in December 2009 the RRTC, concerned about the reliability of the methods advocated by Neville in the hands of novice measurers, came up with a policy that effectively banned the reliance on electronic counters in many situations. Link
quote:
The Electronic Counter is approved for measuring courses for certification only by those that have used this device previously, with the following exceptions:
a It is not be used for measurement of AIMS/IAAF courses.
b.It is not be used for measurement for any big-city marathons, Olympic Trials, Olympic Marathons or National Championship Races.
c.It may not be used for Validation measurements.


I conclude there is still scope for an improved gadget to give handle bar readout. I suspect that this would be appreciated not just by elderly measurers with deteriorating eyesight, but also by younger measurers, and while we are about it those direct km and metre or mile displays advocated by Neville would also help.

I have concentrated here on devices which can help elderly measurers, extend their measuring career. Some will also be of interest to younger measurers. Are there any ideas out there of how to devise gadgets for items 3 or 4 above, to mark the road without kneeling, or for a handlebar readout? Does anyone have other ideas for useful gadgets?
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kenhardwickkenhardwickMember
I have purchased and used several times a video scope.

This one works very well however is limited to use in low light/no light situations. ie..dark or early dawn/late evening or cloudy days. Display hard to read in bright sunlight.
I can press a button to save a picture of currently displayed video. So, I don't even have to write down the counter value. see image below from one of my rides (didn't get date set correctly)




Click here to see Video Scope purchased/price/etc

Last edited by kenhardwick
duanerussellduanerussellMeasurer
Ken - Would a hood/shroud around the display help visibility on sunny days?

As far as Number 4, above, I use a VR electronic counter with a large display, mounted on my stem. I use this for all my 5k & 10k courses, but use it for reference on longer courses. If I am doing a marathon, I calibrate with both Jones and electronic, and have both "clicks" on my notesheet (I can also just leave them in the spreadsheet on my cell phone, and reference them from there. No chance of transposing numbers this way.). I then watch the big numbers, and since they only advance once per wheel revolution, it is much easier to stop at the correct spot with less wobble. When I get to the intended wheel-revolution count, I stop, and my Jones counter is within 15 clicks, or so, or less than one wheel revolution. Makes it much easier to do the longer measurements.

The VR is an expensive ($115, I think) electronic counter, but with proper wiring, it can decrement, if I do happen to be daydreaming and overshoot my split. But, you can get cheap Protoge cyclometers I am told, which can be set to increment once per revolution. Don't overshoot your splits, as they won't decrement, but this is a good alternative to the expensive electronic counter. To be used to get close to splits; not to be used as the measuring instrument.
pauladamspauladamsMember
Mike, I am thinking about purchasing one of the EDM devices and wonder if you could answer a couple of questions:
1. Have you tried EDM laser devices other than the Bosch? Is that the one you recommend?
2. Do you use the EDM to measure your split locations from a fixed reference, or is a wheel still more convenient for that purpose?
3. Can the Bosch still work on sunny days if you use your white reflector? Is the maximum distace reduced on sunny days?

Cheers,
M mikesandfordMember
Paul,
1. No, I have not tried any any other models. I decided to purchase a Bosch GLM 250VF since it advertised 250m range compared to 200m of the Leica Disto D5 and also cost about 60% of the D5's price.

2. I would normally use my bike for measuring offsets from fixed references - much quicker and sufficiently accurate. However when I arrived at the Llandudno 24 hr 1.0267km loop before the race last Thursday, the race director asked me to mark every 25 metres around the loop so they could determine the distances covered on the final lap when the race ended. The loop is around a central reservation of a straight divided road, so consists of two perfect straights with semi-circle turns at the ends. At the time before the road was closed to set up the race there was too much traffic to ride, so I decided to use the laser. I put my small wooden box carrying 4 8cm x 12cm retro-reflectors on the kerb of the central reservation at the start line, and carried my tripod with the laser and set it down at approximately 25m, checked the distance, and chalked the kerb close to 25m. I repeated out to 150m and then decided that the there could be a risk of shining the laser into the eyes of on-coming cars while setting up if I continued to 250 metres, so I moved the retro-reflectors up to the marked 150m point and continued. It took quite a time, but certainly not any more than it would have with a 50 tape, and then there would a risk of the tape being driven across at gaps in the central divide. By the time I reached the 700m point the road had been closed, so I discontinued using the laser, calibrated my bike, and continued using that - much easier. I did check the accuracy of my laser measuring by checking the 700 m point with the bike - The distance on the bike with scpf came out to be 699.4 metres. Adding the SCPF allowance of 0.7m and adding 5 x 3mm to allow for the sloping laser beam over 150 metres and subtracting 5 *16mm plumb bob offset, this gives 700.035 metres - which is good agreement especially since I only used thick chalk lines to mark the 150m points and did not attempt to locate them to better than 2 or 3 cm. Later I was annoyed that after all this marking out, in the end I was allowed to use my bike to record the exact finishing distances at the end of 24 hours, and the 25 points were not used except a rough second check. However it was another good check of the general accuracy of using this laser and of my laser technique.

3. I have had no problem yet with sunny days. At 250m you can just see the 16cm X 24cm target in the view finder if you know where to pick it out against the background. You then turn the laser on - the spot is visible in the viewfinder, but is not located in exactly the right position - you have to aim about 30 cm off to the right and lower. You easily know when you hit the retro-reflectors, since they light up with a bright red spot, visible through the viewfinder or with the naked eye. The telescope mount with good geared drives using worm gears is essential for alignment at maximum range. Dont bother with a tripod that has one of those friction controlled drives used by photographers - they have too much cross-talk between the axes.
Last edited by mikesandford
AdminAdminMember
Paul,
I have a Leica Disto D5. The prices listed for it on the internet are a good bit higher than what sellers will quote you if asked. Leica does not allow them to advertise lower prices.
The maximum distance it will measure is 200m and that is a hard limit due, I think, to their algorithm rather than not being able to receive the returning laser signal. It will give very accurate measurements at 198m, but if you move back 4m it will tell you the target is too far away.
Sunny days seem to have very little effect on the device's ability to work, but it can make confirming a hit on the target more difficult. By the way, reflectors or reflective tape is not necessary for the device to work. It works fine with any smooth, flat target even at 200m. The reflectors are only necessary at long distances to confirm that you are hitting the target.
kenhardwickkenhardwickMember
quote:
3. For a person who finds it tiring to be repeatedly, bending/kneeling to mark the road, we need gadgets to insert PK nails from a standing position, and also to paint/chalk the road while in a standing position.


I now ride my Gold Rush semi-recumbent to measure courses. The counter is a little further away but I can read ok. I use a point right below my seat as a point of marking reference (instead of front wheel axle). For painting on the road, I can stay seated and just lean over. Likewise, when I need to make notes, record a count, draw a diagram, I have a nice, comfortable seat to do just that.
I recently marked all the turns, km splits, start/finish for a 5K course without ever getting off my bike except to do chain repair.
duanerussellduanerussellMeasurer
Mike,

Well, it appears that the counter that I have is no longer available. It looks like they have updated their Totalizer line, and there are improved models available.

But, you do have to wire small switches for reversing the count direction (as I did with mine), so it is not out-of-the-box ready for our use. Plus, some come with an internal battery while some don't.

If you don't mind figuring out how to wire the switches, and making your own mount for the whole setup, then you can go this way. Not cheap, and not without effort, but I like having the larger digits up on my 'bars, so it was worth it to me. Veerer-root site
M mikesandfordMember
Duane:
Thanks. I found the C342 series. There is one, the C342-8652 6 digit LED, which counts up/down using a quadrature signal input. I like the idea of 7mm high LED digits.

I am not sure how the C342-8652 would need to be driven, since all the spec sheet says is that it will accept input from quadrature output encoders. I am obviously thinking of driving it with a pickup driven by magnets on each of the spokes, in order to get enough counts/front wheel revolution that one forget about the Jones counter. If the up/down counting can be made automatic then one would overcome the disadvantage of having to remember to flick a switch.

I don't mind a bit of diy and experimentation. I bought some neat little neodymium magnets which enable me to get multiple pulses per wheel rev on my cheap electronic cycle meter. Has anyone tried one on each spoke to give 36 counts/rev?

Ken:
That looks like a nice comfortable recumbent. I have never tried one. How does the small front wheel compare with larger ones for measuring. I have noticed that people with very small wheeled bikes don't get as good results.
kenhardwickkenhardwickMember
quote:
That looks like a nice comfortable recumbent. I have never tried one. How does the small front wheel compare with larger ones for measuring. I have noticed that people with very small wheeled bikes don't get as good results.

Mike Sandford -


Mike,
My recumbent is extremely comfortable. As far as riding them, they are not much different than other bikes.

As as far as the smaller wheel, I have not done any comparison rides. There are a number of certified courses here in Norman, I will do some comparison rides as time allows.

Not sure why a smaller wheel would be any less accurate. Any thoughts on that ?
AdminAdminMember
What type of tire was on that folding bike Pete? I use a mountain bike for my measuring, and originally used a low-pressure (55psi) tire with some tread. I switched to a smooth 100-psi tire and see much less sensitivity to temperature changes. My guess is the tread and pressure of the tire have more to do with things than the size of the tire.
peteriegelpeteriegelRCMBB Founder
ELIMINATOR INNER TUBE

The Eliminator inner tube was sold in the early 1980’s. I cannot find a current online source for them, and I do not know whether they are still available.

I bought a set for front and rear and used them for a few years. I found the ride harsh, and it seemed that more pedaling effort was required than with my former pneumatics.

The main reason I got them was that I was doing some validation rides involving bike transport by air, and the idea of getting a flat tire scared me, as it could shoot down the entire trip.

The Eliminator inner tube was simply a piece of firm plastic hose, cut to the proper length and inserted into the bike tire in place of the former pneumatic tube. It was sold in various cross-sectional diameters to accommodate a range of bike tires.

My conclusion, after using the things for a few years, was that they were not a good measuring tool.

Those curious for more information can read all about it in Measurement News issues 5, 11, 16 and 30, which can be accessed through www.rrtc.net.

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