Benjamin trying the Leg-A-Wheel proto 4

Here is my colleague Benjamin giving a go at the prototype. Observations:

1. Impossible with current design due to excessive friction
2. Suggested the base wheels to be higher up to create more stability
3. and his jeans gets caught up in the top wheels

By the way, he's an experienced inline skater.  

First real testing of Prototype 4

As you can hear the noise, its because the rubber wheels are rubbing on the aluminium frame. Ila had a wonderfully simple solution, just a few drops of oil. The huge amount of friction that allowed the noise to be made and very importantly allowed me to walk, however vanished with the oil. Luckly we took the video before applying the oil cause after it, it was just impossible to stand on and walk with the smoothest ride possible (if i could i mean). So now the picture is clear, its not as easy as it seems from the video. I'll need to put brakes onto the wheels, to learn atleast.

The team and place!

Well the most important part of this project is the team here:

• Nicola Calitaux, Technican at TFL, UCLouvain - the real technical and ideation partner for all of the project
• Ila Gupta , my wife, sounding board and the real support behind this idea and the maker.
• Others include
• Julien Vervotte, Technicain at TFL, UCLouvain
• Benjamin Berger, colleague at the lab, also responsible for some important ideas and discussions
• and that subir over there ;)

All the work has taken place at the Thermodynamics and Fluid mechanics Laboratory (TFL) at Université catholique de Louvain at Belgium, with the amazing freedom allowed by my supervisor Prof Hervé Jeanmart.

Prototype 4

Finally i have finished the prototype number 4. This one is the most complete one with each set for the two legs. Here for fitting the legs Nicola suggested i use his inline skate shoes for the purpose so that there is no need of other kind of wheel supports(the ones needed to  keep the wheel upright and at a certain angle to the leg).

However its clearly visible the support to attache the shoe to the aluminium stand did not survive the pressure of me standing on it. The welding may have made it weak since its aluminium. Just to give an idea, the main structure looks somewhat like this:

So finally i had to resort to rethinking about the most important thing. Finally i made the following design.

The 2 base wheels are attached the the shoes through a 10 degree bent 3 mm aluminium plate and bolted with spacers together. note that the plates on each side of the wheel are of different sizes to incorporate the shift due to 10 degree angle. The rest of the support and wheel are attached like this:

 And finally its not so difficult to stand on them independent of any support, atleast for a moment now ;)

And ila tried it too, although the shoes are quiet large for her. So we have a first review and needed improvements:

1. We need brakes, for safety and for learning
2. could be made and should be made far lighter than the 2.63 kg each, as of now.
3. there is some constant pressure on the front part of the foot to keep the wheel in the right angular position. this is so because of the flexibility of the skating shoes at the ankle which needs to be minimized.
4. the wheels of one of the wheel sets is jamming too much due to correct fit. To take into account the little irregularities of the rim(spoke holes) and the wheels too, we must make them slightly undersized.
5. sharp edges must be removed.

So today and tomorrow, we will try, and lest see if i can post a video!!

The new wheels!

Here are the newest set of tires, changes the looks and feel completely and hence the title of the post as new wheels. These tires are from http://www.greentyre.co.uk. compared the previous black tyre(from ebay but vintage model) which was 1.2 kg in weight, these are just about 500 gm. Fitting is easy with the tool available from the same company. Really loving it :)

History so far

Currently in the 3-4th prototype stage. Started with trial and error but now have Solidworks models available.

Skateboard wheels being turned to fit the rim dimensions

My little lathe :)

the first prototype of the structure. Used an 'angle' from the hardware store but too heavy

Project description

The intention is to create a personal transportation system that is a cross between a bicycle and a skate. Each leg is strapped to a large wheel, 20" bicycle wheel as shown below in the third prototype.

Such a device will help in skating on rough terrain and village roads. A real application is addressing public commutation problems when large distances are involved to access public transportation services in developing countries.
Check out this interesting video :

Surely its not an easy implementation due to the various challenges. But more prototypes are on the way. This will be presented in whatever form, working or non-working in the makerfaire at rome this october 2013. www.makerfairerome.eu.

To make it really opensource and to see any light of the day, all are really welcome to comment and post experiences and suggest updates. I would be delighted if you have better ideas or totally opposite views. I don't believe in any licensing(as if its a really great idea), so please feel free to use this for any use, it will only be my pleasure.