# PROTOTYPE (16)

Because lack of time, we didn't had the time to make a mold for this piece so the composite hasn't an equal thickness. Overall the result of this test came out pretty nice. We end up with a very strong but lightweight piece. If this production technique is used for the bike we will be obliged to use thicker or more sheets of wood because the strength provided by the test piece will not be enough to hold the bike together.

# PROTOTYPE (15)

A test piece was made to explore the strength and weight of our composite take out bike. This piece was made using thin sheets of balsa wood 1mm thickness. The composite consists of 8 sheets of balsa bonded with polyester resin reinforced with fibreglass matt. Now, we're waiting for the polyester to harden to see the test result.

# PROTOTYPE (14)

Video of working folding mechanism. Now, we're working on finishing the connections & prototyping the composite material.

# PROTOTYPE (13)

The frames are attached to the fork and the wheel. The connection like you see them on the picture ane not the final connection, for this prototype we just focused on the functionality of the folding mechanism, because of lack of money & time. The "real bike" will likely contain better finished connections. The folding mechanism works like a charm and a video will be posted as soon as possible.

# PROTOTYPE (12)

To have a rough sense of the measurements of the bike we held the frame in front of our wheels. The measurements were compared to the once we previously had in mind and they matched very well. Time to assemble....

# PROTOTYPE (11)

The frame was attached together. The connection between the two frames has to be realy sturdy because it intercepts most of the sideways forces on the bike. In the prototype we worked with a nylon tube, threaded on the inside with diameter 20mm. In the "real bike" this part will likely be made in aluminum or steel. Still to be decided.

# CONNECTION (2)

This is a drawing of the connection of the top the bike. It's a hinge to fold the 2 parts of the frame together. The prototype of the connection will come online soon.

# PROTOTYPE (10)

The first connection is finished and will be posted in detail soon on the blog. The photo shows how the frame of the bike will fitted to the first connection. We will reuse the plates that we're welded to the fork of the bmx we bought. This is only a prototype, in the actual bike these plates will off course better match the form of the frame.

# PROTOTYPE (9)

The frame was cut out of the wood. Because of the frames have to slide over each other, their is a curve in the frame. This curve was made by stacking plywood. To test the thickness of the stacked plywood it was bonded with a cord for a quick test. On the pictures at the right you can see the test worked out fine. So the stacked plywood can be glued.

# PROTOTYPE (8)

For the 1:1 functional prototype we tried to use pu-foam but because of the thin shape of the frame the pu-foam started bending which would have negative consequences for the functionality of our prototype and we decided to make our frame in multiplex wood.

# PROTOTYPE (7)

A cardboard was placed on the wheels to explore the form of the take out bike on scale 1:1. After a thoroughly exploration with masking paper & pencil we cut our shape out of cardboard. After cutting the pieces out we came back on our decision and decide to go for a simpler design. Final design became two triangles.

# PROTOTYPE (6)

We bought an old second hand bmx to reuse the standard parts from such as the fork, drive axis,... The bike was stripped and the unneeded parts we're placed by the old metal.

# CONNECTION (1)

First thing we explored, was the connection from the connection to the frame, we came up with 3 main solutions:

1. Clamp the rotating cilinder between two metal slats, which are integrated in the composite frame for extra stability.
2. Weld plates on the rotating cilinder and attach it on the composite fram with some clinches.
3. Instead of using the plates, we split the rotating cilinder to clamp into a triangle structure, which is a stronger solution.

Next step we thought how to lock the cilinder during cycling/storing:

1. First idea was to weld a plate on top and fix this to the frame using a pin.
2. Also weld a plate, but sideways, to attach to the frame (this will be less strong due to the bending direction of the plate and the attaching plate also juts out when folded)
3. This is the simplest idea; fix the position of the cilinder inside using a pen. When folded, you can put the pen back in to keep the fork in place (hole is the same, when cilinder is rotated 180°). To assure the pin from falling out of the cilinder, we can use a magnet inserted in the front of the frame.
4. This idea was to lock the bike by folding it, so it becomes useless to ride for people who want to steel it.
The pens in the front module keep the cilinders in place. By unlocking the bike, the pens can be pulled out and the fork be folded over 180° to the folded position. This idea is quite difficult to realise; also if user loses the key, the bike is useless to drive and has to be repaired...)

# FINAL CONCEPT (7)

On the concept presentation, we had the following feedback:

1. Monofork will skip away/be forced too much when turning
2. Folding point in the middle (under the seat) will be handling high forces when influenced by forces sideways.

With this feedback in mind, we adapted our concept:

1. By adapting the form of the frame in the front, from convex to convave, the double-sided fork has the space to turn instead of bouncing against the frame.
We also copy the same change in the second frame half, so the overlapping form is the same when folded.
2. To make a the connection in the middle firmer, we bend the both frame halves a little (the thickness of the wheel), so the middle connection is aligned and can be made better resistant against sideway forces.
From now on, we will work with a simple hinge, as used on doors, to make this a firm connection.

# FORM EXPLORATION (1)

Because we have the ability of using composites, we can design the bike in a dynamic way.
Also 3D structures are possible to strengthen up the frame.
Some explorations.

# CONCEPT (6)

Because of our folding mechanism the wheel drive has to be under the front frame. So the wheel drive can stay in his place when the bike is folded.

# PROTOTYPE (5)

# BENCHMARKS CONNECTIONS

# BENCHMARK FOLDING FRAME

# BENCHMARKS PEDALS

# CONCEPT (5)

This sliding slot enables a more compact take out bike. Unfortunately in this concept we end up with a lot of material which makes the bike heavier.

# CONCEPT (4)

To end up with a lightweight take out bike we maintained the needed structure for the frame but eliminated the unneeded mass.

# BRAINSTORM (6)

# BRAINSTORM (5)

# BENCHMARKS (3)

# PROTOTYPE (4)

Based on our concept with a sliding slot we made a new prototype we're we eliminated the unnecessary mass, to reduce weight.

# PROTOTYPE (3)

Via a sliding slot the bike is sliced into a compact shape. So far we think is one of the best solutions we came up with. Very easy in handling and very fast.

# PROTOTYPE (2)

A symmetric bike concept that folds in half.

# PROTOTYPE (1)

Prototype is a representation of one half of a foldable bike.

# CONCEPT (3)

A slot was added to make to make the bike easy portable when folded.

# CONCEPT (2)

To reduce weight we reduced the frame of #concept (1) to the minimal needed frame. This is what we then end up.

# CONCEPT (1)

Via sliding slot you can very fast and easily slide the two main composite frames over each other.  When it's folded the bike is very easily to drag around like a trolley, that's the function we focus on.

# BRAINSTORM (4)

# BRAINSTORM (3)

# BRAINSTORM (2)

# BRAINSTORM (1)

Things annotated in red are the things we picked out as most interesting to work with for our further concepts.

# BENCHMARKS (2)

# BENCHMARKS (1)

The text in red tells you why we think this bicycle is interesting & distinguishes himself from the rest.

# BRIEFING

Design a takeout bike for commuters using shapes & manufacturing capabilities of affordable composite materials.