6. Soft Robotics

Research

After the presentation of the topic and the class, I rescue the idea of soft robotics as structures that have this ''soft'' characteristic associated to the soft and flexible contact that different organisms present in nature and that therefore, when interacting with the human body feel much more familiar and closer, natural and less invasive. Contrary to the rigid and cold structures of the traditional idea we have, these mechanisms and structures, presented through different materials that are soft to the touch, are a new way of interacting. Biomimicry and bionics are concepts that we see very present when developing this type of designs and solutions to different problems. This relationship of nature + technology + textiles is very appealing to me, and although they have had a broader development in the field of medicine, the applications are endless.

References & Inspiration

Both in the classroom and in various online pages, I was investigating interesting examples of the application of the principle of soft robotics. Starting from natural structures that, by their nature, can generate different types of movement, to applications that integrate electronic circuits.

I was very interested in the work of Pola Demianiuk, where she conceives garments that can be adapted to the body of the person by means of inflatables. Both the construction of the garment and the specific location of the air channels allow this clothing to close over the body, facilitating access, especially for people with reduced mobility, for example. This user-centered approach gave me insight into how clothing can change its focus to a more functional one, in balance with aesthetics.

I also found the work of In & Motion, who developed a backpack, The Stan pack, that works like other inflatable backpacks, helmets and vests, but it's aimed to give the everyday bike commuter more complete protection around the head, neck, chest and back. It's also designed to work seamlessly as a commuter backpack, carrying a laptop and other everyday work necessities. With the support of various sensors, the backpack can be activated in less than a second as soon as it detects a fall. Under this same concept, Terese Alstin and Anna Haupt developed Hövding, an inflatable helmet that expands from a neck brace. A more portable and discreet way of wearing a helmet but with the same effectiveness in the event of a potential fall.

Digging a little deeper, this study on machine weaving for the creation of powered soft objects invites us to explore various ways in which through, the very nature of weaving, one can integrate and develop ''tendons'' that power the fabric, as well as integrate textures, sensors, and delve into the properties of the fabric. I was struck by the term associated with the research mentioning computational craftsmanship and CCS - Human Centered Computing, the latter similar to what we see in industrial design.

Going more to the fashion side, an interesting reference is Kunihiko Morinaga, founder of the Anrealage brand already known for integrating technology in his collections. One of his collections, WIND, makes use of fans that inflate the clothes, providing an atmosphere of fresh air, giving a new dimension and silhouette to the clothes. The designs play with the idea of wind as an invisible but powerful force that transforms the garments in real time. Although we could say that the use of this inflatable feature is more aesthetic, I consider that its application is relevant, giving a new look at how textiles interact with the body.

At the Fablab ESAN, there was an example of a 1 and 4 arm soft gripper. It was made based on a 3D printed mold, RTV10 silicone and connected with thin hoses and a syringe as an air pump. It worked quite well and it was possible to appreciate the mechanism that activated it. I particularly liked the feeling it gave, when twisted around the arm, it is true that this type of materials completely change the perspective and contact, it felt alive. I also made a test so that it can hold some fabric. Making the printed mold, I think it helps the pieces to be more complex and have more three-dimensionality.

From the previous research, and according to what we saw in class, we have several soft and flexible materials with which it is possible to work from the construction of air channels, or through connections with sensors that generate a response in the structure, either by changing its size, or by generating contraction and expansion movements mainly. Among the materials observed are: knitted fabrics, TPU, PVC, plastic and metallic films, paper and silicone.

Inflatables first tests

Starting with 2D inflatables, according to theory the most accessible way to make one was to use materials that can be fused with the action of heat, an indispensable requirement to create a chamber or vacuum duct through which air could circulate. For this I could use a baking paper as a layer between both pieces of material, or also using the laser, but taking care of the parameters so as not to cut the material.

I went for the first option and made 3 small tests to test the theory and see how the material behaved before making a larger structure. Since it was a rapid prototyping, I cut by hand the baking paper, the pvc and a plastic film that I found. The channels were branched and crescent shaped, plus one that had rather large round spaces.

• I placed an entrance so that it would be easier to insert a straw or tube through which the air could enter.
• I heated the homemade iron for the test at the maximum temperature, approx. 100°.
• In the case of the pcv, I placed the shiny, plastic side inwards so that it could fuse with the other side, while the paper went in the middle.
• In the case of the metallic film, the shiny side was facing inwards.

In general they worked quite well, although the air did not flow all the way to the last space. The metallic film one caught my attention, it seems to me that it has potential.

Silicon first test

To start this test, I made a moodboard with different structures, mainly seed pods, which had shapes that reminded me of movement and branching, so they seemed appropriate to work on the basis of an abstraction of their structure.

Starting from the moodboard of structures that caught my attention, I made some sketches in Adobe Illustrator. I find this software quite user friendly when making vectors, which is what I needed for the exercise.I find this software quite user friendly when making vectors, which is what I needed for the exercise.

After developing each piece of the mold, I cut the base, the frame and the inner channel in 6mm acrylic and the base and the channel in 4mm acrylic. The parts list would be as follows: - Air channel design. - Contour frame for the air channel - Contour frame for the base - Air channel base - Base for the frame only

After we have the pieces cut, we must join them together. In this case I used contact glue, and for the silicone, we used RTV10, which is quite flexible and uses a 2-3% catalyst. Using a scale, we used 100 g of silicone and 2 g of catalyst.

For the preparation of the silicone, we previously prepared the work space, that is to protect the table and use gloves to avoid skin irritation.

The silicone is of a single component, and when adding the catalyst it is necessary to mix homogeneously but fast, since it can harden half empty.

In general in 1 hour it should be dry enough, however, there were a few failed attempts. After we took it out of the mold, we used a little more silicone to glue both pieces. An important clarification I must make is that, in this test, I did not contemplate the air channel path as such, so I had to make some incisions in the mold to allow the air to flow. A small design error. In addition, it is suggested to place a textile so that the base does not expand and the effect can be better appreciated.

Another important detail is the opening through which the air will circulate, as a result I had very thick pieces so it was difficult for the air to circulate without escaping.

Second test

Analyzing the mistakes and successes of the previous tests, I developed new templates both for cutting in baking paper and using them with PVC, as well as for the acrylic molds. For the PVC test, I chose to imitate the shapes I had developed on my moodboard, taking into account the ducts through which the air will pass.