Category: Design & Construction

At the time of my registration at SunTrip, I had about 6 months to build and experiment my prototype, which limited the search for partners, and therefore the budget too. I obviously watched the presentation how to turn an electric bike into a solar bike by Bernard Cauquil. I admired his selection of technological solutions. Surely he had hoisted the bar very high. But the cost price of his machine was quite a deterrent to me. Besides, I like the DIY (= do it yourself), I like to be self-sufficient. So, when it was possible, I rather opted for the cheapest solutions, although I knew beforehand that they were not the best. This allowed me to have a vehicle for a reasonable price. The diagram below reflects the cost of the solar bike (out of partnership), it does not take into account the R&D budget that I have difficulty evaluating. The total is below the €3300 bar.

Visits: 77

While hiking, walking or cycling, I learned to pay attention to the weight of my equipment. I learned a lot about ultra-light walking sites (MUL) especially randonner-leger.org/. The basic principle: is this equipment indispensable to me? To find the right balance between comfort, safety and lightness. I apply the same principles to bike riding.

For the SunTrip, I knew my bike would be heavier than a normal bike and my choices were often guided by the concern around the weight. The bike I bought weighed 25kg. I managed to reduce his weight to 19.6 kg. How? For example by removing accessories such as the steel luggage rack (1kg alone!), fenders, etc.. and replacing the suspended fork with a rigid carbon fork (2 kg gain).

On the other hand, my new reconditioned battery gained weight: 3.6 kg versus 2.8 kg originally. But that extra weight doesn't upset me. What for? Because it corresponds to an increase in its storage capacity: It goes from 9.6 Ah to 28Ah because the repackaging company offered me to increase the number of cells using all the available space.

Visits: 98

Today, Elisabeth Dounon sent me the aluminium profiles machined by the apprentices of the CFAI of Châlon-sur-Saône. Thank you to the young, to their Professor Vincent Daka, and to Elisabeth Dounon! (Read more) These parts that support the solar panels allow the two side panels to slide so as to reduce the width of the trailer. I wanted to have the possibility to reduce the width of the trailer mainly for safety reasons, especially for the crossing of the big cities. The idea came to me when I saw the solar bike of the Cazaspe (SunTrip 2015) But my realization is less sophisticated.

Visits: 95

With the prospect of a partnership with the CFAI-21-71, I was today presenting my bike to a group of young apprentices in alternation training. I was asking for their help with the machining of aluminum tubes that support solar panels. As a matter of fact, I had machined aluminum parts for sliding the lateral solar panels to reduce the width of the trailer. But my hand tools do not allow to obtain parts with precise and regular ribs, which leads to hinder or prevent its good fonvtionnement

Visits: 108

Throughout this project of creating a technical object, I was able to realize how complex the creation process is, because indeed:

• many parameters are taken into account (of the order of physics);
• some parameters are closely correlated (while others are independent);
• some parameters are the result of a personal choice or a preconceived idea, others are simply based on physical laws (NB: it is sometimes no easier to remove an obstacle linked to a preconceived idea than another linked to a physical law).

It is not a linear approach, but cyclical or rather spiral. We go through phases of information research, design, research of suitable material. Then come the construction and experimentation phases. When we do not achieve the desired result, we return to the phases of research, design, construction and again experimentation.
Sometimes, after several cycles, we reach the intended goal, and we are happy!
When we do not succeed, we are less … We are then led to question certain initial choices, certain parameters. And then the cycle begins again …

Visits: 126

Today, accompanied by Elisabeth Dounon, I visited the training center of the apprentices of the industry in Dijon (CFAI 21-71). For me who loves technology, it was a pleasure to discover their equipment, especially the room dedicated to robotics. Then we considered how the apprentices could be associated with the process of creating the solar bike.

I had already seen this French humanoid robot, Nao, at events around digital education.

Obviously, in the lobby, this sign has taken my attention.

Visits: 113

Pilot testing of a step-by-step motor programming on Arduino: Driving an engine… By Stephane-suntrip2017 driving tests of a servo motor

Visits: 107

Today, the FabLab Kelle Fabrik organizes a workshop to learn how to program an Arduino module. I was enthusiastic about it. What relationship with the construction of a solar bike, will you object? Well, I had seen that some participants in Suntrip 2013/2015 optimised the recovery of solar energy by orienting their solar panels. So the idea germinated to automate this process and I began to dream that, while pedaling, my panels would orient themselves in a dynamic way according to the Sun. Let us hear well: they would orient themselves along a single axis, that of the trajectory of the bike. And of course, I would activate this automatism only in the absence of wind (I was able to realize that with wind, even weak, the panels had to remain well horizontal).

Visits: 107

Two days before this workshop, I had installed the free and free blender software on my personal computer. By discovering the complexity of the interface, I quickly abandoned the exploration, discouraged. And tonight, after 2 hours of discovery guided by the animator of Kelle Fabrik, I almost manage to finalize my project! I can't believe it. It's great, sharing, collaboration… Thanks to the FabLab to exist!

It must be recognized that there is a special, exciting and almost magical atmosphere here.

Visits: 111

How will I go about making my solar bike? I do not have an electrically assisted bicycle, I know very little about capturing solar energy … Suddenly, the questions flow in all directions:

• for electrically assisted bikes: what type of motor? Hub motor or bottom bracket? Motor on the bike or on the wheel of a trailer that pushes the bike?
• what power for the battery?
• how can the uneven power of the sun charge the battery? How is it regulated?
• For solar panels: how much? What power? What dimensions? Where to install them? On the bike, on a trailer, on both? How to fix them?

To sort out all these ideas, I make a mind map: https://app.wfor resources on the internet, there is no shortage of them. Of course, I come across "THE" precursor: From France to Japan by solar bike

Visits: 146

Today I met Jean-Claude who is a physics teacher in Dijon. I asked him all the questions that had come to my mind on the previous days:

• How to calculate the energy consumed by the bike to determine the required surface of solar panels?
• How is solar energy regulated by nature so fluctuating?

He enthusiastically embarked on clever calculations and brilliant demonstrations, which I sometimes only partially understood, but it was so reassuring to meet someone who knows! Someone who dissipates the fog around us! I will leave with answers and full of new questions, particularly on the practical aspects of the implementation of these basic principles. Before leaving, Jean-Claude tries my electric-assisted bike. For the photo, he poses near the sign bearing the name of his street: "Path of the solar", I'm on the right track!

Visits: 119

According to Wikipedia, an electric power-assisted bicycle (V.A.E.) is a bicycle equipped with an auxiliary electric motor and a rechargeable battery. Legal definition of a V.A.E. In France, a bicycle with electric assistance must conform to the European Directive EC2002/24 and the French standard NF R30-020 laying down the following general principles:

• The rated power of the engine shall not exceed 250 watts,
• The assistance works up to the speed of 25 km/h, not beyond,
• The support is provided only when the user is pedaling.

A vehicle will be considered a moped if one of the following conditions is fulfilled:

• The rated engine power is greater than 250 watts,
• The assistance operates at a speed of more than 25 km/h,
• The support works when the user does not pedal, for example using a joystick.

In France, such a vehicle must be insured like any moped and requires the wearing of a suitable helmet. Moreover, it is not allowed to take the bike paths.

Visits: 146

This afternoon it was my "first time", my first try with an electric-assisted bike loaned by the gable-on-street cycle shop. It was a very informative outing for a novice like me, my impressions were contrasting: on the one hand, a great satisfaction to climb the coast of vises at an unusual speed, but on the other hand, what frustration on flat ground when The assistance leaves me as soon as I exceed 25 km/h, the high weight of the bike is then felt! I'll have to get used to it… But on reflection, in recent years, when I randonnais bike with my saddlebags (tent, sleeping bag, clothes, food etc…), my average speed has always been less than 25 km/h. This will still be the case this summer, especially since the course in the Alps will have a difference! Under these conditions, the lack of assistance beyond 25 km/h will be more rarely felt.

Visits: 135