Turbocast: Low Temperature Thermoplast (Streifeneder)

A couple of days later I received a parcel from Streifeneder with some of the 'Turbocast' which they produce.

 

Turbocast was much more difficult to mold. It stuck glued to my tools. It glued to the hair on my hand, which was sort of painful ... (I ended up shaving my hand before continuing experimenting with Turbocast). Somehow this material just felt more stubborn than Apolit.

However, eventually I got used to the material and was able to get some decent results out of it. More on that topic soon.

Apolit: Low Temperature Thermoplast (Minke Props)

A couple of days ago a received a sample of Apolit, a low temperature Thermoplast by Minke Props.

First off, I have to say that I love this stuff. Where it not rather expensive, I would buy a ton of it...

It was quite easy to mold, I did not burn myself, nor did it pull out any hair after having hardened on my hand. If you need material for instant prototyping this is very interesting stuff.

Take a look at how my first encounter with Thermoplast went.

If you toss it into boiling water it turns soft and transparent in under a minute. I assume you could also bake it in the oven, though it would definitely need a much higher temperature. I was a bit worried that this material might melt if left in a car or something. However I think that would require very, very high temperatures (not saying these are impossible) as air is not all that good in transporting heat. I think its really the fact that water 'transports heat' so well which makes this work so effortlessly.

If you don't like the way its molded, just throw it back into the water. It will go back to its original (flat) shape and become moldable again.

Cutting it is no big deal, however if you use thicker material that could be a pain. I figured this out later, but obviously if you cut it while its still soft. A knife or scissors would go through it like butter.

I also tried sanding it, which did not work very will. Sanding it feels like rubbing an eraser on paper. Carving it with a sharp knife works better. Sawing it should work fine.

I added some self adhesive Velcro. This works sort of fine, but if you want something really permanent, you may want to additionally secure it with screws or something. 

By the way. I hope to soon receive a ton of sensors by images. This 'wristband' will then be used for mounting the stretch sensors for measuring arm rotation. More on that in a later post thought.

Images Stretch & Flex sensor

(scroll down a bit to go directly to the videos.)

As I said, I received two sensors by images the other day. A flex sensors and a stretch sensor (find documentation here and here. Unlike a potentiometer these do not come with a voltage divider to simply measure the resistance, so I had to go about constructing my own. Basically what I did was put a resister between ground and the sensor and attached a third cable to the sensor right before where I attached the resister. (The same way as you would do it for a photo-resistor or any other resistive sensor i guess...)

Here are some pictures of the first readings I took with the flex sensor:

straight:

and bent:

I then went about to see if I could actually use them as I hoped. (The flex sensor for measuring the hands clasp and the stretch sensor for measuring wrist rotation)

Here's an image of my flex-sensor-glove setup:

And here are videos of both flex and stretch sensors in action:






I am a bit worried that the signal from the stretch sensor might be too weak, but I believe I can improve this when I actually go about constructing the whole thing (I might not be using the optimal resistor in the voltage divider and have to experiment with location of the sensor etc.)

The flex sensor/glove combo works so well that I've had everyone who comes close to my room wear it and try it out for themselves :-D

The Pictures

Well, as you see, I found myself a mannequin. You can see lots of the design features I describe in the post below, so If your interested it may be better to read my previous post first and then check back with the pictures when I start to confuse you.

And yes, she creeps me out as well. And I cant believe people actually use these things. I mean. This doll in no ways resembles the shape of an actual person...

but yeah, it does enable me to see what I am doing a bit better than when I am actually wearing it...