Fabrication:

We started the fabrication process by water jetting the wheel side and wing. This was good and bad. We found a lot of little problems that we had to fix, it helped us find problems in our design and fix them. It was bad because the wheel side and win that we cut are not perfect. We then started to design for fabrication. The wheel halves were hard to fabricate due to undercuts and poor designing. We simplified the design and changed both halves to be symmetrical. We also changed the right wheel mount. It was previously too big and wasted material. We refined the design to make it smaller and cleaner.

PCB:

There are many different electronics elements in Transit Wheel. To connect them we have the main PCB. The PCB holds the Arduino, two analog to digital converts, a gyroscope, an accelerometer, a compass, two level shifters and voltage monitor. This allows us to manage all the sensor on transit wheel in a compact way.

Pressure pad:

To measure the amount of forward or backward lean that the user provides, we have pressure pads on the wings. We spent a lot of time looking at sensors but could not find one that was long enough for our purposes. We decided to make the sensors ourselves. We are using velostat, a material that is more resistive the more pressure put on it. We will have strips of that glued to a flexible PCB with the other surface touching the metal of the wing. This will allow us to measure the placement of the person's weight to see how much they are leaning.

Gear Box:

The gears had to be held in place using two gear mounts, one on either side. The Planetary gear set has two layers of three gears. The Gears have bearings that ride on three rods. The two gear box halves have to be attached somehow. We had to add three extra rods to hold the gearbox halves together. We can't put screws through the gear shafts because the process of drilling and tapping them would make the shafts bulge and not be as precise as we need them.  The gearbox is attached to both wheel sides. This is for two reasons. First, the gearbox will align the wheel halves, it also disperses the force evenly along the two wheel sides.

Getting to and from the train is not an enjoyable experience. Train stops are not always conveniently located, scooters are not a practical transporter as it is hard to fit a scooter in your bag, and bikes are not allowed on trains forcing riders to risk having their bike be stolen. So, we set out to create an enhancement to the T riding experience that was fast, compactable, and lighter than the existing ways of getting to and from the train. From the beginning, we intended to create a device to enhance the T, what we believe is an already existing and functioning mode of transportation. We had no intentions of creating a device to replace the T riding experience. With this in mind, we set out to design the Transit-Wheel.

Lock

To make the lock mechanism we first started by sketching multiple ideas and designs. The first one that we looked at used something that stuck out from the wheel side and held the wing down. We decided that that would take up too much space in the wheel. The next design that we looked at was a piece inside of the wheel that hooked onto the wing and prevented it from moving. The next design involved a piece sliding down into slots in the hinge. This would prevent the wing from moving by locking the barrels in place. The final design works very similarly to this except it locks from the inside of the wheel side.

Handel

We decided to redesign the handle because all of our previous ones didn't work as well as we wanted them to. The new design is built into the wing and the wing and the handle are one piece. The Wing now sticks out from the wheel side and bends up. When the two wings are folded up the wings meet. There is a hole at the tip of the wing creating a handle. When we first made the handle design there was a lot of wasted space. The hole was moved down and the flat part was majorly shortened.

Motor

We spent a lot of time trying to find a motor that met the specifications we need. We looked at  high torque low rpm pancake motors. We found two companies that make them Kollmorgen and Printed Motor Works. We originally contacted Printed Motor Works in a previous studio and the quote they gave us was too high at the time. We contacted them again and asking for a motor with a gear box. And they quoted us 700 usd we then realised that putting their gearbox on it didn’t make sense because we would need our own gears on top of that. We were about to contact them again and then realised that they were advertising their motors as a drop in replacement for Kollmorgen motors, so we started looking at those motors. We spent days pouring over datasheets and found the ideal motor for us. We called a distributor and found called them they got back to us and said the motor would cost 1400 usd and would have 12 weeks leed time. So we will from Printed Motor Works. All that work was for nothing.

Pressure pads

When we started to find ways of controlling the speed of the transit wheel we looked at two forms. The first was an exeloromater and the second were pressure pads. We decided that pressure pads were a better way to go. The problem was that all the pressure pads now are all too small and not precise enough. To fix this we used velostat and custom PCB The velostat would be sandwiched between the wing and a custom flexible PCB. We would have strips of velostat that would act as pressure areas. There are going to be eight pressure areas arranged in along the foot.  This would be able to sense when there is a change in pressure on your foot and where the change is so it will move.

In the future, we will actually order the motor because we need to design the inner wheel around that motor and that is a lot of work we haven’t even started on. We wanted to work on that this week but there were complications with the shipping and we don’t know if the motor has been actually ordered yet. We need to finish the pcb design for the pressure pads and the main controlling pcb. We need to figure out how we are going to manufacture the wings because creating complex curves like that is not easy. We need to decide what buttons transit wheel will have and where they will be.

Getting to and from the train is not an enjoyable experience. Train stops are not always conveniently located, scooters are not a practical transporter as it is hard to fit a scooter in your bag, and bikes are not allowed on trains forcing riders to risk having their bike be stolen. So, we set out to create an enhancement to the T riding experience that was fast, compactable, and lighter than the existing ways of getting to and from the train. From the beginning, we intended to create a device to enhance the T, what we believe is an already existing and functioning mode of transportation. We had no intentions of creating a device to replace the T riding experience. With this in mind, we set out to design the Transit-Wheel.

In the preceding two weeks, we spent the bulk of the time designing the outer shell of the transit wheel and searching for a motor, during this two weeks we started designing the wheel, but also incorporated feedback and returned to heavily modified the body design

Body Design:

We spent a lot of time redesigning the body of Transit Wheel. It used to have a rounded top with organic looking curves on the wings that met to make a handle. We had a design review at SPI. We talked about a lot of things, like the wing lock and the body design. The engineers there told us that the wings and wheel cover would be difficult to make and very expensive. We decided that that wasn't realistic to fabricate so we shifted approach. Now the wheel cover has three edges on the top to make a trapezoidal shape. The wings match the shape of the wheel side, and when they are folded up all the edges meet. The edges on the wings are folded up to increase the strength of the metal. Since the handle is no longer attached to the wings, it's fastened to the wheel cover.We also decided to use steel instead of titanium because of money, steel is also a lot easier to work with. When we went to SPI we talked a lot about the wing lock, many ideas were talked about, but we decided that just screws are the mode reasonable approach due to time. 

Wheel:  

When we started working on the wheel we had to think about a couple of things. First, we had to figure out how to reduce friction when it turned. The most obvious way to do this was bearings, the problem is that bearings that are as large as we need are either too expensive or don't exist. The next problem was fastening the two wheel halves together. If we used screws the two halves could move slightly and get out of aligned. We decided that using screws and a small locking mechanism on the edges where the wheels meet. 

Gear design:

A critical aspect of the wheel design are the gears, which transfer and amplify the torque from the motor to the wheel. Since our gears need to fit inside the wheel, with the motor, we decided to use a planetary gear system. Planetary gears are known to be suitable for high-torque, compact applications. The struggle with gear design started with finding suitable software in which to design them.

I tried multiple different software to design the gears I started using gear generator.  I stopped using that because it does not make accurate teeth and there is no good way to import them because it uses polylines instead of curves. I started looking at Solidworks add-on for gear generation that got good reviews. I found a software called Eassistant through this site calling the best gear generation tool. I found out after doing more research than I should have had to that Eassistant does not do gear generation. In the past I had used the Solidworks toolbox I knew that they had gear model but did not think they were customizable I found through a video that you can customize the pitch multiplier and tooth count. Getting the proper gear ratio was challenging I thought we would need a much larger ratio to get enough torque. I made a 3 layer planetary gear set with 2 caked gears stacked and an annular this took a long time to get to this solution. When David and I calculated the gear ratio we realized that we only needed a 2 layer gear set with one set of planets and annular gear.

Getting to and from the train is not an enjoyable experience. Train stops are not always conveniently located, scooters are not a practical transporter as it is hard to fit a scooter in your bag, and bikes are not allowed on trains forcing riders to risk having their bike be stolen. So, we set out to create an enhancement to the T riding experience that was fast, compactable, and lighter than the existing ways of getting to and from the train. From the beginning, we intended to create a device to enhance the T, what we believe is an already existing and functioning mode of transportation. We had no intentions of creating a device to replace the T riding experience. With this in mind, we set out to design the Transit Wheel.

During this studio we redesigned the breath sensing flower to make it smaller and more manageable to hold while in use. The first iteration of the this studio’s flower had small petals that did not poke people in the face while they have the flower close to their face. In order for the smaller flower to close we had to redesign the center pin that connects to the petal frames. We moved the attachment points for the petals frames out closer to the petals, but this version of the flower was still not able to close completely.

For the second iteration of the flower we modified the center pin to allow the flower to close, and we also added a locking mechanism to hold the flower open or closed. We moved the attachment points on the center pin down and in towards its center. This helped the flower to close but the petal frames hit each other, causing some of the petals to overlap. The locking mechanism that we added to the flower is very simple. The center pin had two small divots in it, and the flower base had a spring loaded ball in it. As the center pin is pushed up or down, the ball snaps into the divot. The center pin can then be pushed passed the ball easily.

The third iteration of the flower added fillets to the pieces, as well as a cone to direct breath towards the breath sensor. For this iteration, we refined the design of the flower by adding fillets to the base and center pin. These help make the pieces stronger so that they will not break as easily in the wind. The cone that we created snaps onto the top of the center pin, and has space for the breath sensor to sit at the bottom. It directs peoples’ breath down to the sensor, and it also reduces noise that would be picked up by the sensor otherwise.

The current flower now has lighting, a transparent cone, and tapered petal frames. We added lighting to the flower by placing an LED upside-down in the breath cone. In order for the light to diffuse evenly throughout the entire flower, we printed the breath cone out of transparent filament. This not only allows light to pass through, but it glows when the flower is open. To make the flower close completely, we made the tops of the petal frames thinner so that they would not hit each other and cause the petals to overlap.

For the past six weeks we have been working on Grove, an interactive forest that will be at Burning Man 2016. Last studio, we made a Grasshopper file that generates leaves for the trees. We also came up with the idea for a stacked plywood platform for the trees, and designed a flower that will open up to reveal a breath sensor.

This studio, we did a complete redesign of the breath sensing flower. The new design is much simpler to make and use. The petals of the flower uncurl to reveal the sensors while looking like a more natural flower.

We began by designing the petals of the flower. The new petals have a more simple frame that consists of just a single piece that goes down the middle of the petal shell. The shell of the flower now acts as the hinge of the flower, reducing the amount of complex parts needed to construct the flower.

As we designed the opening mechanism we started out by making a base and a center pin. The base of the flower cupped the petals and had slots for the ends of each petal to fit into.The pin is designed so that when the user pulls the flower down the pin will stay put, pulling the ends of the petal frames up with it. The first center pin had eye hooks coming out from its sides, which we soon learned stopped the flower from opening and closing correctly.

The second mechanism consisted of a larger base and an inset center pin with eye hooks on top. The base was made larger in order to fit an inner layer of petals, but we later decided not to use these. The eye hooks for the center pin were moved to the top so that when we inset it into the base they would still be accessible. We ended up removing some of the screws holding the petal frame to the shell because it allowed the petals to curl like a real flower petal.

The final flower for this studio has a slimmer, more natural base and a center pin that connects directly to the petal frames. We got removed the inner petal slots on the base, allowing us to make it smaller. We also chose to give the base a more cone like shape so that it would match the design of the rest of the flower. We removed even more parts from the flower by attaching the petal frames directly to the center pin. Instead of having eye hooks, the center pin now has slots for the petal frames.

Over the next two weeks we will shrink the flower petals, as well as adding the sensors and a locking mechanism to hold it closed when not in use.

The breath sensing flower went through a complete design overhaul over the past two weeks. For the first week of the studio we worked refine the existing design of the flower. As we did this we were also working on getting the opening mechanism working. We recreated the flower base to make the flower easier to open. The base was split into two snap together parts in order to make it easy to 3d print, and the bottom piece was made larger to allow the strings from the flower to come down at a less steep angle. The new flower base helped with the ease of opening the flower a little bit, but it was still fairly hard to pull the strings. In order to open the flower we designed a crank mechanism that would pull the flower strings down as it turns. We soon realized that for this mechanism to work the strings would need to be easy to pull. If they were not then the crank would either break or not move at all. When created We designed and 3d printed a stem for the flower with a small hole in it to which the crank would be attached. We also made a second piece of the stem to add two holes close together in order for the flower strings to come out of the stem right above the crank. This method seemed to work fairly well, but it was hard to turn the handle.

During the second week we got the humidity sensor to work for detecting breath, and we came up with a better design for the flower opening mechanism. We linked Arduino and Processing so that the humidity and temperature sensor values could be read by Processing, and then used them to influence the sizes of two colored circles on screen. While the sensors may not be the most sensitive, we will be combining them with code to separate peoples breathing rates from the noise around them. Since the string and crank method we were using was hard to implement and use, we decided to start experimenting with a much simpler design. The new mechanism utilizes a pulley mechanism that will reduce the number of parts that we use. Instead of using springs, strings, and a crank, the new mechanism will just have a stem with a locking slider that pulls the flower petals down. The petals will be attached to the sliding ring using a stiff part instead of strings, allowing the slider to both open and close the flower. Throughout the next two weeks we will continue working on this new design in order to make a full model, and possibly even the final iteration before production.

Throughout our second Grove studio we focused on choosing a final leaf pattern and design.  We started out trying to modify our simple cupped leaf design.  We had only cut them out with scissors so far, so we started designing them in rhino.   We had to pay attention to the shape, pattern, and how the leaf will hold together.  Working with the idea that the trees are an extension of the body, we also worked on making the leaves with lung patterns.  While designing the leaves, we took pictures of lungs and traced them in rhino.  We altered the trace to make the shapes more abstract, and then started cutting different versions of it. 

After designing a few lungs, we decided to start layering the lung pieces to make them have more volume.  The first pair we designed was a lung with a layer of veins running through it.  We used the lung pattern we had designed the day before and traced out the veins to layer it.  This design worked well because it made the lung look more lifelike, but it was hard to tell where the different layers started and ended. 

After we had worked on the patterns, we started looking at shape and arrangement.  We came up with a few ideas that we liked, but decided to start with having many long and thin leaves fan out from the branch.  We took our lung design from the day before and started stretching it out to make it look more like a leaf.  After making it longer, we had to start looking at the rim design.  we had a lot of trouble making it because we didn’t know exactly how we wanted it to look, but we finally settled on a very abstract and organic curvy edge.  This design comes with many complications.  We have to make sure that the attachment is flexible so that the leaves sway and can move around,  but we also have to make sure that they will not be destroyed by the wind.  

For the rest of the studio, we worked on making a small Grove.  The point of this was to make 10-15 tiny Grove trees and figure out how they can be arranged and design. We started by making all of the bases for the trees.  The bases we made varied in height and size.  We decided that each tree would have one thick trunk and six small branches.  These were attached by holed in the base that they could stick into.  The one thick trunk took a place in the middle of the base and the six thinner branches stuck into the base around it.  The branches wrapped around the trunk on their way up to the top where they fanned out.

Overview

Our group has been working on Grove, an interactive art piece that will be installed at Burning Man 2016. The project is based off of Pulse and Bloom, a past Burning Man installation created by artists from around the world. The goal of this project is to create a quiet meditation space that people will be able to interact with.

Our project is divided up into three main components, the tree base, the leaves, and the breath mask. The base of the tree is designed to give people a place to sit and meditate near the tree, and the roots of the tree will for seating between the trees for socializing. The leaves will give the forest of trees some shade, and will cast beautiful colored shadows on the ground to draw people to The Grove. Lastly, the breath mask will be a flower that people breathe into to change the colors of the trees.

Experience and Brainstorming

Early in the process we started thinking about The Grove as an oasis. We focused on the leaves of the trees first, and how we could get them to provide shade. We thought that if we used two layers of laser cut material, that they would leave enough room in between the layers to defuse the sun. What if there could be a kinetic aspect to the leaves, a part that would move with the wind? We started thinking about a way the leaves could have sub holes in them, which would have little spinners on them, and as the wind blows, the spinners spin. Some of the spinners would be prisms, to create rainbows, others would be mirrors, and some would be a solid material. As the spinners spun around, they could possibly bump into each other, which would give the leaf like sound of a forest, triggering another sensory experience. 

We also started thinking about how can a viewer connect to a tree even if they aren’t the ones directly breathing into it. What is the second hand interaction with the space around them? What if there were organic laser cut chair blobs that someone could sit down in, and put their feet on a sensor that would read their heart beat being pulsed through the fiber optic grass around them? Lots to think about.

As the group continued to brainstorm, we thought a lot about the human interactivity with the tree. What if the user didn’t have to pick up something to breath with the tree, but rather breathed directly into the tree? We explored having the user go into a prostrated pose, which is a bowing down pose often used in meditation. We ended up turning away from this idea because it would be a little weird to breath with the tree, but not actually be able to see the interaction happening.

We like to think about The Grove as a conversation between the humans and the trees. There is a cool project at the MIT museum that is a fake tree but when you put your ear to it, you can hear crickets. It would be very powerful if when you put your ear to the tree you could hear it hum.

Base design

One base design we considered was similar to a nest. Under and entangled in the tree roots would be organic wooden structures that the user could lounge and perch on. This one was better than the first design in the sense that it could fit more than one person. The downside of this design is that it uses a lot more material and is a lot more work to design. It also loses that open feel, it's more clumpy and rocky.

The last structure design we worked on was a very minimal design. Each of the roots would still crawl outward from the tree, but two or three per tree would curl up in a circle on the ground, to create a separate space. In each root circle would be a cushion. This idea is my favorite out of the three because the human and tree are in a symbiotic relationship. It is like a tree hug. This design creates a very flexible space; it can be a personal space, or also a group space. The downside of this design is that the metal would get hot in the sun, and we wouldn’t want the users to burn themselves.

Leaves

Our studio started out with brainstorming.  Our first ideas for the leaves were mostly pattern- and shadow-oriented.  We thought we could make the leaves similar to the pattern of a real leaf.  Real leaves are too small for people to clearly see all of their veins, but the leaves on our trees would be big enough for people to appreciate them.  Etching the pattern would give us the shade that we want, but there would be no holes in the wood to see through, so there would be no shadow-patterns on the ground.

After considering a layered design, which would give the leaf depth, we also started thinking about how we could make each leaf a hollow structure.  Our first idea was to have little rods of wood connected to one flexible wood spine.  Because this takes hours to design for each leaf, we thought that maybe we could use pieces of extremely thin wood to curve and structure the spine.

While we were thinking about how we could get the leaves to cast beautiful shadows, we also considered coloration. You could make the leaves cast colored shadows on the ground.  You could put a layer of transparent acrylic over the plywood design.  The acrylic would have to be tinted very lightly so that you could still see the wood design.  Our other idea was to laminate two layers of acrylic with oil in between.  The oil would be different colors, so you would see it “swimming around” on the ground all day.

When we started building, we made a scale model of one tree.  Two of us formed the tree trunk and base while the other two of us worked on the leaves.  We traced two biological leaves in rhino and illustrator and proceeded to cut them.  It took a while, but they matched the aesthetic language we were aiming for when they were done.

After experimenting with an etched wood leaf, we cut a couple pieces of leaf-shaped felt for the end of the branches.  This helped give us a sense of ideal leaf size and placement.  When we finished that, we cut out our first wooden leaf.  With that iteration, we started figuring out how it might attach to the tree.  We realized that for our final Grove we would want to have a much more physically flexible material.  The wood just didn't look very much like an organic leaf because it was so rigid.  From there, we spent some time making paper leaves.  We used that same pattern on each, but made very different shapes.  When these were finished, we draped them over the felt leaves that were already on the tree.

After trying paper, we started working with it a lot more.  We decided to make a structure that had many little leaves connected to make it. We focused on making each of the segments first.  The easiest way to do this was to make a net.  While making the net, we had a lot of trouble envisioning what shape the net would actually make, so we ended up making many different nets and seeing what I could make out of them after they printed.

The next concept we tried was a flexible palm-inspired leaf made of wood.  This iteration used two pieces of wood locked into each other with dozens of thin slits for flexibility.  These leaves would provide the right amount of shade.  We cut it out of wood and it flexed as we intended, so we decided to try cutting it out of rowlux to overcome the appearance of wood.  The rowlux looked better then all of the other materials we had tried.  It was very flexible, while maintaining structural strength.

Flowers

In order to change the brightness and color of the trees in the grove, we will measure the breathing patterns of people sitting near the trees. A flower shaped breath mask will measure user’s breath, and then the trees in the grove will recreate the breathing pattern using colored lights on the trees. The flower will open when picked up, and close again when put down. We have been working on making a sturdy flower frame that will be able to withstand the high wind speeds at Burning Man, while still looking like a delicate flower. The first flower was made out of paper. This did not work very well since the flower would not close after opening, so we moved on to using a more rigid material. The second flower was made of wire that was hot glued together. It looked really cool and would open and close well, but since it was glued together the pieces fell apart easily.

After that we decided to work more on the petals than the flower itself because the opening mechanism would work with any flower we made. We created 3d printed petals, as well as laser cut ones. Each of the frames retained the same basic design, but some were not curved, some had a Rowlux shell, and others had mounts for a hinge. After making all of these petals, we chose to continue working with the 3d printed petals that could later be made by welding wires. The current flower has a 3d printed base and petals. The pieces are attached by small hinges, and springs make sure that the flower closes when the user lets go of it. Each petal has a piece of Rowlux one the back to give the flower a more realistic look, and the base has channels for routing strings through that open and close the flower.