Prototype 11

Prototype 11

In the prototype 9 we made a cast out of fiberglass and polyester. The client liked this, but would really like to use silicone because of the way this feels. In prototype 10 we tried to make a glove out of the silicone by making a mold of his hand and pouring in the silicone. This was too complicated so we decided to combine the two.

We used the principle of the fiberglass, but we decided to 3D print it. We found out that PLA can be molded when heated. This is ideal, because every person can mold it to his or her hand. 

+	–
Lot of support	Too thin
Easy to slide of the handlebar	Not enough room for silicone
Adjustable to every hand

Next steps:

Make a new, thicker and more sturdy print

Make more room for the silicone

Make a parametric slide for the handlebar, different widths

Prototype 10

Prototype 10

After the feedback from prototype 9 we reached different conclusions with Sander. 

1) Firstly, we should make the whole shell with a soft material (similar to the silicone). 

2) It will be interesting to create a one piece product, casting the silicone with the attaching parts. 

Sander was interested in the next steps, so we decided to work together with him in the Atelier. This way, he could see the next steps we were going to take and give us feedback at the moment. 

Thanks to this, we saw that he likes the idea of having a one piece part attached to his arm and the possibility of attaching it to the bike and taking it off.

Then, we decided to make a mould of his arm to have the exact shape.

To make the one piece shell, we thought about different options. 

1) Casting the whole shell with silicone

+	-
The whole shell will have the same feeling, and Sander likes it.	The shell will not have a strong structure.
Thanks to the elasticity, there is no need of a closing system.	Depending on the type of silicone, the price may increase.
We could use the exact measures of his arms by using the mold.	It will be difficult to cast the silicone together with the attaching system.
We could create a shell with a stronger material and then cast the silicone in it, making it much stronger.

2) 3D printing the shell in a rubber material

+	-
The shell will have a strong structure.	The material is flexible but not soft enough (not the feeling that Sander likes).
Thanks to the elasticity, there is no need of a closing system.	The connection with the attaching system will have to be different.
We could use the exact measures of his arms by using the mold as a reference to model it in CAD/CAM.	It would be more difficult to respect all the measures when modeling.
Possibility of adding another material to make it softer.

3) Contacting a prothesis company

When the concept was defined this way, we thought about the possibility of contacting a prothesis company to help us develop the concept. This way, we found that the company Aqtor! was interested in our project.
So, we are making an appointment to meet them to discuss about it and see which options we have.



Company link: https://nl.aqtor.be/?SID=oeuukstk5tebkn6e2uqg2epaq2

Results of the mold:

Once the silicone mold was cured, we poured the plaster in.

Now we have an exact replica of his hand.

Prototype 9 & protomorphing

Prototype 9

With this prototype we try to use the best options tested. So, we used the sliding system to attach it to the handlebar and a strap to make it stable. As we had different aspects to test, we decided to make this prototype protomorphable.

This way, we created to different shell shapes, one smaller than the other:

We created three different straps:

Silicone

Silicone

Strap and silicone

And we used the connection to the handlebar that he liked most but we also tried two different lengths, that way he can test his reaction when taking his arm off.

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+	–
Shell shape; smaller, big enough to be comfortable, but still safe feeling	Shell shape; bigger prototype too big
Strap; silicone feels good, also no closing system needed	Shell shape; sharp edges, should be more rounded
Attaching system; easy to connect	Attaching system; small one too small, left side of the slide should be closed

Prototype 8 & protomorphing

Prototype 8

With this prototype we try to connect the prototype to the handlebar by using a slide system. The hand is attached by a cotton strap. The strap is bigger than the previous one to divide the pressure and also to protect the hand from the cold winds.  

Protomorphing:

We put double sided tape on this prototype so we can change the sort of cushion we use to absorb the shocks.

1

2

3

4

Testing:

The strap is hard to put on, but easier than the previous prototype.

It would be easier to use one big slide instead of two. It is easy to click in, but difficult to click out. The clicking noise helps. This gives auditory feedback. A slide to the side would be better than a slide to the front.

+	–
Easier than prototype 7	Strap hard to put on
Easy to click in	Difficult to click out
Clicking noise	Should use 1 slide instead of 2

  

Extra questions:

Do you want support for wrist?: no Do you want to be able to change the size of the strap?: yes