Document, document, document: A Lego robot in process

Today I am inspired this guy who developed a robotic Lego AT-AT walker and made it onto the MAKE magazine blog for it.  He did a really great job of documenting his process and it’s a reminder that I need to do the same.

As part of my current robotics-related independent study I am developing a Lego six-axis robot–it’s pretty involved!  The idea is to build one that will be roughly proportional to the one pictured below, which is almost done being installed at Ball State’s Architecture Building:

KUKA Robot at Ball State

The most complicated part is the wrist at the end of its arm, which incorporates three distinct axes in a very small space.  Transferring axial rotation across other axes takes some mechanical engineering, for which I’m not really trained.  Thankfully others who are have shared their work, and I am learning a lot from a couple official Lego sets I own.  There are probably many ways to go about this particular problem, but I came to the conclusion that I would need a custom gear–which is also a good excuse to try out our new Formlabs 3D printer.  Here’s what I came up with:

Modified Lego Gears

These are based on a standard Lego 20-tooth beveled gear that looks much like the one on the right, except that the Lego one has a cross-shaped opening at the center instead of the circular one pictured above.  The circular opening permits the gear to rotate freely around an axle rather than only in concert with the rotation of the axle.  The compound gear on the left is two 20-tooth gears joined at an offset that allows the gear to straddle the opening at the center of a turntable.  This arrangement is pictured below (left), with the custom gear approximated with the standard Lego gears.  The custom gears are being printed on a Formlabs Form 1+ resin-based 3D printer (below right), which so far is producing some pretty amazing results.

WP_20140912_002    Formlabs Form 1+ 3D Printer

I’m still working on getting into the habit of taking pictures at every stage, so unfortunately I don’t have a picture of the first go at printing the custom gear.  I will update this post as soon as I do.  In the meantime, take my word for it that the printed gear is at the core of the following first pass at a functioning three-axis wrist!

Lego robot wrist


UPDATE: Here are the results of the most recent print.  This is a revision of an earlier iteration in which the gear teeth did not taper to facilitate better meshing with other gears.  As mentioned above, the circular opening at the center allows an axle to rotate freely within in it; the opposite is true also–the gear can rotate freely around an axle.

WP_20140914_011   WP_20140914_015

Architecture and Self-Expression

Aaron Betsky’s article in The Berlage Institute’s Hunch magazine entitled “Critical Architecture: The Question of the Art in Building” (unfortunately not published online) presents an insightful picture of the architect’s dilemma, but one that makes certain assumptions that may not be valid.  He says, “As free agents, architects are put in a difficult position. They have to find a way to define what they do as more than just making something that disappears into [the client’s demands for functional, efficient and self-image-projecting buildings].”  Architects have turned to art and language as means for self-expression resulting in the concepts of utopian and unbuilt architecture and in site-specific or installation works, a medium they have shared with the artist who aspires to built work.  According to Betsky, however, these forms of self-expression lack the functional impact that full scale built works can have on the world.

Betsky’s first assumption in this analysis is that the architect has to work in a traditional architect-client (and perhaps -engineer/-contractor) relationship.  Today there are a number of models that allow an architect to work for himself or in an emerging rearrangement of practitioners that brings the architect closer to being contractor and/or manufacturer.  For example, as Jonathan Segal advocates, if the architect can begin to operate as developer in addition to his primary occupation as designer, he has the ability to express himself and get work built–and he has demonstrated this successfully, obtaining financing from banks and investors and producing creatively designed and engineered buildings that redefine norms within the building industry (see  Another example is the composites industry in which architects are often directly involved with the design and composition of materials for built work.

Another assumption that Betsky’s article appears to make is that site-specific and installation work is either not architecture (being the architect’s attempt at being an artist) or not of as much value or impact as a full scale work that fits a traditional definition of a building as “something built that we can inhabit and use”.  But the site-specific “artwork” that Betsky says is now prevalent in architecture is often far more front-and-center in culture and society than buildings that fit standard categories for built work, and with the architect’s sphere of influence, which Betsky says is greater than that of the artist, such works have the potential to impact as many people as any other structure.

What does a building that makes for a better world look like?  This is perhaps at the heart of the discussion for Betsky.  Is it a specific functional category of building such as a habitation or hospital?  Is it a high quality structure, one designed according to sound architectural design principles and a sensitivity to the environment and long-term sustainability?  Or, as Betsky suggests, is it one that makes a statement?  If it is the latter, a highly expressive pavilion might have greater potential than a multi-family housing development.

On the other hand, self-expression can take many forms, and it is conceivable that an architect could thoroughly express herself fully in the service her firm provides to her clients.  There is a certain creativity that is required (and which can be a self-imposed requirement) as part of design when it comes to addressing environmental concerns and building efficiency within a tight budget.  There are certainly those who would say better design should cost less.  If this were our focus, we would not harm society and we would have to opportunity to impact it on many levels including elevating design within the common sphere, perhaps through such means even making a statement through a multi-family dwelling.