23 May 2007

thesis intro - take 1

1 Introduction
The basis of constructionist learning is that one externalizes one's ideas through some type of construction material. During the construction process one needs to learn, appropriate, and functionally apply certain ideas in order to realize what one conceives. The properties of the materials are not only crucial to what one does and does not learn, as they facilitate or obscure the ideas inherent in the construction, idealization, and thought process, but also crucial in determining which populations are allowed access to the educational content inherent in the process of constructing with the given materials. In this thesis, I will propose and examine an open set of construction materials that incorporates wire and other locally available materials in an effort to bring to the forefront the need for accessibility in understanding key concepts in structural and mechanical engineering in communities that have historically been under-represented in these fields; I will explore the theme of interactive, artistic, mechanical creations as a way for builders to express and incorporate their own interests and stories into their designs, and thus, find a personal access point to concepts in mechanical and structural design; and I will explore the range of possible artifacts and styles of expression afforded by these methods and materials, and in doing so, will explore the range of potential new educational content such a process could provide.

Pre-fabricated construction kits, such as LEGO, K'nex, Meccano, Erector, etc., have been around for many years and can be a great way to introduce people to constructing and robotics; the kits' materials enable rapid and solid construction, as the parts and their connections are designed for this purpose. However, the cost of these kits, especially the robotics kits, can be prohibitively expensive. As a result, only certain people, communities, and schools are able to access the kits, and thus the concepts enabled by using the kits. This is particularly true for poorly-funded and poorly-supported schools, such as those potentially found in developing countries, rural areas, and inner-cities. Instead of relying on pre-fabricated kits, I will focus on using wire, a material which can be found almost everywhere in the world, as the basis for mechanisms; other locally available materials, such as cardboard, as the basis for structures; and the GoGo Board, an open-source/open-hardware Logo-based board, as the basis for computation. By exploring the use of these materials I hope to show that deep concepts in mechanical and structural engineering can be understood through using simple materials and tools that are available and accessible to a larger population than the population currently reached by pre-fabricated construction kits.

In addition to allowing greater accessibility, the use of wire as the basis for mechanisms allows for the incorporation of locally specific materials as well as the local knowledge about these materials and their roles in the community. The use of locally specific materials enables a community to access new educational content and to appropriate this new content for their own local needs. This same ability to incorporate local materials also allows the builders to add their own aesthetic touches into the design. This is different from pre-fabricated construction kits where aesthetics outside of the ones afforded by the kits become simple adornment on top of an assemblage of parts. This ability to have aesthetics integrated into the design allows for a different type of construction to be explored, a construction where the aesthetics and the design are united into one whole. Combined with computation and sensing through the GoGo Board, it is possible to have, for example, a set of constructions centered around interactive 3-D story telling/animation. By having a kit focused around such interactive, artistic, mechanical creations, it becomes possible for the builders to express and incorporate their own interests and stories into their designs, and through this, mechanical and structural design becomes more personally accessible to learners who might otherwise have no point of interest.

Many people have achieved successful learning about systems, feedback, control, and some mechanics through working with pre-fabricated construction kits, yet because these kits' connections and shapes are pre-designed by the manufacturer, several key concepts in mechanical and structural design are left unexplored when using these pre-fabricated kits. Because the pre-fabricated parts are designed with connections and spacings in mind, the builder has to provide very little thought as to how to space and connect. Thus, using a pre-fabricated kit means quicker and more intuitive construction, but also means that the users of these kits never learn how to reason their way through the design process from material to part. By not going through the thought process from material to part, builders miss out particularly on concepts in geometry, in joining, and in material choice. In addition to providing an access point for new hands-on educational content, the ability to design your own parts also allows for the inclusion of aesthetic considerations into the part designs and the design of the whole.

In addition to providing the design for the parts, the makers of these kits often provide step-by-step instruction guides on how to connect the given parts into the intended whole. Combined with the pre-designed and pre-fabricated parts this affords almost effortless construction. Although many people often de-construct the final whole to use the parts in their own constructions, the fact that the beginning user can usually never make something that is as well-designed as what is first built can lead to dissatisfaction which results in a possible lack of motivation for future constructions and therefore for future learning. However, typical to design, the affordances that ease certain aspects constrain others, and such is the case with having construction start with the materials rather than the parts. The time it takes to construct something solidly starting with only the materials and tools is significantly longer than with a kit that comes with pre-designed parts and instructions on how to use them. As experience working with the materials and tools, as well as experience with thinking through the whole design process from start to finished machine increases, the time it takes to construct a sturdy, aesthetically pleasing, and functioning machine decreases. In an attempt to address the potential rough start of working with materials instead of pre-fabricated parts and in an attempt to break from the tradition of providing a step-by-step instruction booklet, I will attempt to provide a learning framework for gaining experience about constructing one's own designs with accessible materials and tools through the use of a hand-drawn booklet focusing on the “grammar” of mechanisms and structures, the design process, and possible ideas on how to find or scavenge local materials. Additionally, because mechanisms are notoriously hard to explain with static representations, I will provide a collection of animations that represent the funcions of the different mechanisms. All of this will be openly available via the Internet. It is my hope that through this work, I will enable the learning of mechanical and structural engineering concepts to as wide population as possible.

18 May 2007

mechanisms

so i figured i'd talk about mechanisms and the ways i've noticed the kids approaching them.

it seems that the kids find it easiest to grasp simple rotational motion off the bat. the fact that they can plug the motor into the gogo board and instantly see it run aids in this; it's obvious what it does. many groups have made merry-go-rounds, roundabouts, etc. from there, many groups have gotten the idea of increasing the diameter of rotation to make it look like it's going "faster"... making car chases, etc. i haven't counted all the projects, but it seems like even if this isn't the idea that ends up being used in the end, it's one of the first ideas to be had.

from there, one increase in complexity comes when using the motor as a wheel... a simple sort of rotational to linear motion, and something that is available for observation in their everyday lives.

these mechanisms (rotational and wheel) come about from a direct observation of the affordances of the motor. and maybe if the group is starting without a clear idea of precisely the motion they want, they're more likely to allow the materials to dictate their design more throughly.

more complexity comes when the kids decide to use the motor with a string as a simple winch. this is something i had not thought of, but it makes sense as a concept that is available in western society with the idea of a reel (rod and reel). this first came about with the pultneytown p7 group in wick, and after that, as their photos got introduced into the photos i showed in the beginnings, more and more groups did this.

another sort of motion that kids ask for, but don't know quite how to get, is some sort of jumping motion or rocking back and forth. i try to ask them if they have seen anything like this, but a lot of kids haven't. a couple of kids came up with a crank/single link system; they were all mechanics' kids, i found out upon questioning. usually i have to suggest this idea by suggesting that they look at some of the photos/videos of what other kids have done in hopes that they will find something useful to them. i also try to have at least one physical example of a single link system. a common mistake kids make is that they try to hold the link still at the pivot on the wheel. they then seem surprised that it doesn't work. when this happens, i never tell them they've done it wrong, but rather, i ask them questions about why they think it doesn't work. usually after one or two questions about what they think would happen if the pivot isn't a pivot, they figure out that it should move.

a couple of teams are able to use/understand two linkages, but only when the mechanism is presented to them as something to play with and build off of.

jose valente suggested that i try to be clear and aware of my effect on the kids. my effect becomes clear when i question and steer them towards certain mechanisms... or even just suggesting that they go look at other groups. my effect is also clear with the two bar mechanisms. i don't think any of the kids would've come up with that on their own in the time they had (neither the two hour workshops nor the two day ones). just from my own experience, i don't know that i would've come up with it if i hadn't have seen an example. so i think that the role of examples, providing examples, and providing a suggestion as to where to look is important.

i also think that it's important to look at the way these groups approached their projects. some grabbed a material and were like... this is cat's fur! we will make a cat! and others were like... this is the motor, we can make a wheel, we'll make a car. even others were like... we want to make this, how can we make it move like we want. so, either an idea sparked from the materials (be it the motor or the craft materials or whatever) or a goal formed from their own imaginations and finding the materials and methods to fit that. those seem to be the two ways that the groups approach things. and with those two approaches, there are different results with different mechanisms. it seems to me that the groups that have their own motion in mind are more likely to push what they can do with the motors/programming, whereas the ones who get their mechanism idea from the observable affordances of the motor/wheel seem to make machines that either drive around or spin.

17 May 2007

crank/winch



another mechanism animation from sadie and me.

and here are some of the things that the kids in scotland built using this mechanism

this is the first group that thought of doing this. after them, there were more.
tank
a group of teachers make charlotte's web
hickory dickory dock (teachers)
raising a flag
little red riding hood
skier going up a hill

crank with one bar



an animation Sadie Scheffer and I made of a crank with a single bar.

These are some models made by young people in Scotland which use this mechanism:

singing girl
boat
sunset
easter bunny
car crash
drummer
man blowing bubbles (plan)
man blowing bubbles
man kicking soccer ball
flapping bird
ship crashing into iceberg
girl jumping on trampaulin (close-up)

crank



an animation Sadie Scheffer and I made about how to make a simple crank out of wire.