Measuring the state of a road - Project

[Grelinette]

The French road network is in a deplorable state: holes, bumps, cracks, overhanging manholes, subsidence, etc. (the media talk about it more and more often)

I'm part of a bike promotion association, especially in the city, and we often see the deterioration that worsens: it is increasingly difficult to cycle, even some bike paths are now difficult to borrow.

cycliste.jpg (14.26 Kio) Viewed 2992 times

In September 2018 (already 1 year), the government launched an extensive Map-Bike, but we do not see much happening for now.

We have the project to (try to) make a map of the quality of the road network of the town! ...

The idea is to design a device to measure the state of the pavement of the local road network, especially bike paths. For example a device on wheels, towed behind a bike, which measures the condition of the road surface during the trip. One can imagine a simple small bike trailer with onboard measurement equipment that will scan the state of the road by optical beam or vibration measurements to give an assessment.

A technical school could offer this project to students: the subject seems to have a technical content high enough for students to tackle.

At first, it is a question of making a list of specifications.

Do you have ideas for such a project? ...

[Grelinette]

I reactivate a little bit by giving a little pedal stroke because we must have a meeting soon with teachers of technical schools to present this project.

To put it simply, I guess it should not be very difficult to design a system that detects jolts when driving on bumps, holes or deformations of the roadway.

This is what happens when you are on a bicycle (without suspension) on a damaged road: you can feel all the faults of the road and it is very unpleasant ... Moreover, in writing this observation I tell me that a tubular system instead of the stem of the bicycle saddle could play this role of measuring the condition of a road! Like what, "From the discussion springs the light", said the philosopher Nicolas Boileau, even when one discusses with oneself!

It remains to be seen how to interpret the results to give an overall score to a delimited cycling route.
For example, to evaluate a bike path of one km, we can have a constant path but with a poor quality coating all along, or conversely, a good coating but with a track cut every 50 meters by a sidewalk, a gutter or a crossroads, as is often seen in urban areas.

[phil53]

As for me what I find unpleasant in Nantes is the bike paths at the same height as the sidewalk, these tracks pass on all boats out of the house. A track continuously made of donkey with one side a risk of falling into the gutter. I prefer those marked on the ground but the same level as the road.
It is also dangerous to use bike paths on one side and then on the other side of the street, with each change a risk for the cyclist.

Regarding the project, I work in a company that helps, guide startups on the side industrialization looking for partners.
If it helps.
From my point of view I think the idea of ​​the trailer is bad, a small embedded system is certainly better and less expensive to manufacture.

[Ahmed]

A suspended saddle (as mentioned above) expresses well the defectiveness of the ground because it benefits from the inertia of the weight of the cyclist: it is enough to adapt a transmission of these movements to a stylet just inscribing the plot of the oscillations on a cylinder rotating at constant speed and voila!
This problem clearly shows that a mobility solution like the bicycle, presented as "light" in environmental terms, is in reality rather demanding on this particular point of the condition of the roadway and therefore of its maintenance. Of course, a certain adaptation of the vehicle would allow more basic pavements to be tolerated, this is what we see on ATVs, but this is done to the detriment of other factors ...

[thibr]

an application to record the accelerometer + GPS of the phone?

[Grelinette]

... From my point of view I think the idea of ​​the trailer is bad, a small embedded system is certainly better and less expensive to manufacture.

Thank you for this remark. Indeed, the trailer is probably superfluous and a small system embedded directly on a bike would be less expensive and easier to design.
I saw in the trailer the advantage of more volume to ship a larger equipment, even a heavy weight, but also the ability to measure a wider road strip (the width of the trailer, about fifty cm or more).

A suspended saddle (as mentioned above) reflects the defectiveness of the ground because it benefits from the inertia of the weight of the cyclist ...

Using the rider's weight as an "amplifier" is surely a very good idea, and therefore the saddle stem seems to be the appropriate point of measurement. On the other hand, inscribing the relief of the road surface on a rotating cylinder risks producing long garlands of graphics that are a little difficult to use!

The idea suggested by one of the professors interested in the project and use the GPS of a smartphone to locate the place of the route where the measurement was made. In a second step, an analysis of the collected data will allow to give more details and a note on the state of the road for a precise route.

For example:
- Overall score for the chosen route: ... (average quality of the coating)
- Number of obstacles encountered: ... (holes, manholes, sidewalks, protruding branches, etc.)
- Discontinuity of the course: ... (boats leaving the house, crossing the road, etc.)

etc ...

[Ahmed]

... registering the relief of the road surface on a rotating cylinder risks producing long garlands of graphics a little difficult to exploit!

It's just a matter of rotational speed: it needs to be slow enough to provide a usable plot.

[phil53]

Electronically there is a way to do better.
An optical ray that sweeps the pavement over a meter wide coupled with a vibration sensor would give very good results exploitable on computer.

[Forhorse]

An accelerometer attached to the bike frame is more than enough. The bulk of the job then is writing an algorithm to analyze and exploit the data.
First of all, I would say that it is a project with a large computer component / information analysis.

[GuyGadebois]

http://michel.kasser.free.fr/Allaz-Kass ... 6-2016.pdf