i built a lot of robots with parents over the winter break. i built a robot arm and refreshed on inverse kinematics; more specifically, make sure your servos are rotating as you expect: IK goes counterclockwise since angles increase that way, but your servos may increasing in a clockwise direction… a simple map(theta, 0, 180, 180, 0) will fix your problem if you catch it.
processing takes in x,y coordinates drawn on the screen and spits them out to arduino over serial, which does the inverse kinematics and spits out the theta values to the servo
it does not face well, in part i have derpy three year old code
this processing code takes a lot of processing libraries. thresholds image, performs canny edge detection, then a walking algorithm (look at each black pixel by scanning image in x and y, see if neighbors are black as well, then walk along that pixel) to turn the edges into vectors. then output to robot, but robot is limited in resolution (arduino servo library) and cheap hobby servo overshoot.
below you can see preview in python. (basic code, I basically copied the output from processing into a text file and added some python code to that to plot the values)
is to check image is within the working envelope of the arm. IK is fixed with arm “up”.
problem of walking algorithm: adds a box around the image. irritating. need to rewrite code. looking into open cv.
used http://www.sgr.info/usbradio/download.htm and calibrated my servos to zero… took a while to realize it *can* and *should* read the current values, guess my wires were loose, but the values because a lot easier to input. used the kk2 screen to fix some controls that were reversed from what the kk2 expected (left = left and not right, etc.). zeroed all the values on the kk2. turns out (minus the flipping controls) I could zero just as well on using the trim knobs on the controller itself.
went to visit NASA space museum in houston. they had little robot that made and served you froyo. adorable.
also, some regal looking hexapods in the actual NASA workplace.
at MITERS I got a robot arm working with lots of help from MITERS / London Hackerspace / john from BUILDS. For robot arm competition. http://robotart.org/
i’m now robot art-ing. here is using Fengrave on a black and white image with appropriate offsets to produce gcode (well, limited to G0 and G1 commands)
face code still derp. (streaks are because i wrote gcode translator, and it goes to x,y,z position instead of x,y and then z). too many x,y points. draws slowly.
michael made crayon extruder (=metal tube + power resistor) and also pen mount. crayons = hard to control flow rate. started making square, then pooped out a lot of melted crayon. alas.
learned a lot of patience dealing with old manuals, 20 year old operating systems / controllers. main issue turned out to be a dumb calibration assumption (robot had arrows; should have ignored them and used indentations instead).
also, i learned about oscilloscope rs232 decoder! had to invert to get it working properly (zeros are high in rs232?). scope ground, tx line. bam, now you can check whether you are actually transmitting all the carriage return and line feeds you need…
turns out that right in Medford, MA there is a waterjet being used in production at a bakery called “Edelweiss Patisserie”.
Based on their website, they are essentially a contract manufacturer for baked goods. So cool!
We produce more than products that fit your business needs—we create pastries that enhance your product line.
Our customers are category leaders in the food industry, including supermarket and club store chains, restaurants and cafes. They demand innovative, unique products to meet the needs of their sophisticated consumers and their own margin and turn standards.
We invest in product development and have the manufacturing flexibility to create almost any dessert our customers could imagine. Our business is driven by what our customers want, and we deliver! When we say we offer only the highest quality products, we mean it.
I emailed the contact email, and lo and behold, a few weeks later, the very kind owner of the place replied! He was held up by the Easter holidays.
Thus, one spring day we drove over to Edelweiss.
We got a sweet tour of the place by the owner himself. The place is gigantic (the pictures don’t do it justice). Here, the owner talks a little about the supply chain and inventory management needed to run the place.
There was a recycling machine that crushed boxes
into neat cubes, WALL-E style 🙂
Industrial quantities of strawberries
and trash bins full of tapioca starch put the batch ingredients we use for putz’s (where I lived during undergrad) liquid nitrogen ice cream event (cryofac) to shame.
Vat of oil half as tall as me.
There were horizontal bandsaws used to plane pastries
Here’s just a few croissants
The ovens were pretty cool because
they had this mechanism inside that would lift an entire rack of pastries up so that they could be rotated and evenly heated while baking. Sort of like an industrial version of the toy vending machines with the claw you use to try to grab plushies.
Giant chocolate machine, chocoma (I think the name is funny)
waterjet machine for baked goods
Note: This waterjet uses water only (at 60kpsi), no garnet (it’d get all over your cake! :P)
Finally we came to the highlight, a waterjet from ?Spain? that cuts baked goods (and is in use all the time when the plant is running).
Here’s a closeup of the interface.
The designs are pre-programmed, there’s a simple shape editor, and then other designs are emailed in to the manufacturer to be converted into DXF or whatever
video of it cutting
in more detail
what was cut:
right side (pump?)
left side (intensifier?)
They told this awesome story of the seal on one of the components breaking, and then they cut it themselves on the machine. Secretly, they are engineers now too 🙂
Here’s the part they fixed (maybe a water trap??), which is to the rear of the machine on the left side:
The grille was a little worn!
face detector for a high-tech version of punching in and out
Marcela helped me with this. We dumped all the powder (100g) from the Jamila bag into a bowl.
added a cup of lemon juice
and mixed it
and then covered and waited 12 hours.
The next day (after the 12 hour wait) I added in 1oz (the whole bottle) of cajeput essential oil
After another 24 hours, I poured the mixture into an ice cube tray.
Then I stuck it all in the freezer in a plastic bag inside aluminum foil (to keep the light out).
I offered henna at one of my parties. Ankur drew a narwhal
and Julian drew electrical engineering symbols / circuits. It’s shiny because we used a spray bottle filled with lemon juice and sugar (to make the lemon juice sticky)
This is what it looked like after a day (the darkest is day 2).
On my other hand Marcela drew a tree and I doodled a robot.
I felt a little awkward about it (someone asked me if I’d gotten these at a wedding… which was not the case).
I chose to apply it with a cake decorating bag and some reallly realllllly fine cake tips from karenscookies.net. The idea is that with the coupler, changing out tips would be very fast. The Ateco coupler worked with with the wilton tips and the ateco tips I got.
Ateco Tip 00 $1.39
Ateco Tip 000 $1.39
Ateco Coupler $.079
Wilton Decorating Tip #1 $1.39
However, in practice, I think in the future I would go with rolling my own cones to have more control over the tip. I’m told you can cut at a slant and that way, by controlling the angle and pressure of application, vary the line width a lot.
I also gave some thought as to the cultural appropriateness of doing this. In the end, I think I concluded that henna was used in enough different cultures that as long as I stayed away from traditional / religious designs that I didn’t understand / wasn’t a part of, it was ethically okay.
Nonetheless what I really want to convey is that the meaning behind cultural appropriation and cultural appreciation is being inappropriately used and instead of holding an angry, vindictive attitude towards others, we should be the wiser person and teach them and show them the beauty of culture.
and want to strive to be more in accordance with it. For a while I was offended at the idea of adding cheese to dumplings, until I talked to my dad who thought it was a great idea (just like easy tacos!) and realized perhaps my sentiment derived out of an insecurity about how Chinese I was.
Overall, I really liked the xojane article below.The basic idea here is that our parents had everything to gain by their culture being accepted, while as 1st generation (for me, “ABC” or “american-born chinese”) we may overcompensate for being “between cultures” (and others, not me, have had the experience of being mocked for their culture) and be hostile towards other people adopting our culture.
I bleached it once for 90 minutes and then again in three sections, the shortest section was 30 minutes and the longest 80 minutes.
The ombre effect didn’t really come out. I suspect the first bleaching needed to have been part of the gradient as well.
The bleach I did myself, but I had Holly J.’s help with the hair coloring. It didn’t look like much at first (wet)
But dry it looked pretty nice.
Joico Vero K-PAK Color Hair Color – Red 1 9.79
+ orange, yellow, peacock green, cobalt blue, amethyst purple (yes that adds up to a lot >__>). It was from sleekhair.com
(shipping took about a week).
I chose that after reading the reviews on this site
I was a little underwhelmed with the intensity of the colors (they’re not super BRIGHT), but they’re very nice colors (they look very … soft and natural in the sunlight). I choise Joico after reading the reviews on this site: http://fashionista.com/2014/10/rainbow-hair-dye
The hair bleach I got locally, from Sally Hansen’s Beauty Supply store near Target in Somerville / Union Square. It probably cost me around $25.
The hair looks really nice with a waterfall braid
Here for instructions:
Here’s how my hair looked after two days in french braids. So fluffy! Haha.
I wanted to replicate a dress I have for Open Hardware Summit (which I’m using as an excuse to start and finish a lot of projects, from heels to dress to earrings), but found it too difficult. Instead, I found this super-easy dress, which consists of just four pieces:
It is called an infinity dress because of all the ways you can wear it
My attempt came out more like a miniskirt due to some errors I made and lack of additional cloth. It also falls strangely on the front due to the lack of cloth pulling it down. So it goes.
To remedy it, since I have no more of that cloth and the store that sold it (Sew Low) is now closed (owner retired), I can 1) sew a different color underneath 2) wear a slip underneath 3) wear dark tights.
Additionally, the stretchy orange fabric causes… issues when it’s stretch thin. Ala wet tshirt problems. 🙁
It was all pretty straightforward. I’ll just document my measurements and cloth dimensions here.
chest center to armpit back 10.5”
bottom of ribcage to top of breasts 6”
For the circle, my inner radius was 4.25” and my outer radius was 19.75”. Here is a picture (with the inner circle unfolded to show that the cloth is folded into quarters). I made the waist smaller than intended and it fit fine on my waist without falling down or being too small (although it did get on the smaller end of acceptable after I finished sewing everything to it).
I mark it, I used a piece of chalk and a tape measure, then anchored my right hand at the center of the circle and swung the tape around.
My rectangular cloth was 10” by 28”.
My long straps were 10.5” by 97”. I pinned them extensively down their entire length and the cutting was straightforward, although extremely tedious. The mat actually helped a lot, since I could line up the clean edges on the mat and actually see through the fabric to the white lines on the mat and mark down the entire length.
I used a single stitch, the straight stitch, no zigzag stitch needed (the second row on the machine), because the orange fabric was super stretchy.
The only part I found tricky* was which side to sew the rectangle (turned into cylinder) on onto the dress. I almost sewed it on the wrong side. It should be sewn with the top part of the right side is facing you and the bottom part of the right side is facing the mat, and the wrong side is facing itself on the inside. That way, when you put on the dress, the right side is facing out. The right side of the cylinder is facing the wrong side of the straps. The right side of the straps is facing the right side of the skirt. The bottom part of the right side of the skirt is facing the mat.
*I messed up on the skirt mostly because I wasn’t really paying attention and was listening to a podcast 🙁 I folded it in half and cut out the quarter circle, instead of folding it into quarters. Unfolded, I got two useless halves of cloth instead of a circular skirt.
All told it took me 8 hours to go from first reading the instructions to wearing the dress.
I played extensively with gradients (ombre) this time around. I think I need to find some China Glaze, a lot of the nail polishes were very dilute, so I had to go back and dab more on to fix the gradient.
I also used a nail polish pen to draw summer / water themed decals on top of the background gradient colors. I’m most proud of the one with the conch shell, though you can’t see the colors too well in this picture.
Wow. Just wow. I spent three or four days just trying to get my phone to show up on my computer, and even rooted my phone. I tried everything — booting into windows and installing kies, mucking around with “mtp-detect” and “adb devices” and more on ubuntu, editing rules files.
Everyone kept saying “enable USB debugging” or “install mtpfs” or “sudo vi /lib/udev/rules.d/69-libmtp.rules ” or “it doesn’t work on usb 3.0 ports” (I have a lenovo thinkpad x1, gen 2). Worse was the “just go to Settings > Storage >click three dots in top right > USB connection mode > Select MTP”
In the end, all I had to do was dial *#0808# to get at a menu that was completely, utterly hidden on my phone. I’ll say it again,
Just dial *#0808#
And select “MTP”
and now, when my USB is plugged into the laptop, I actually get the “select MTP/PTP” menu.
I’m helping with a conference this weekend (it’s free and at harvard saturday) with a pretty sweet speaker lineup, and has lots of topics on mental health, which i thought some of you might be interested in.
Please join us for an event focused on the brain and mind research: the MindEx conference, on Sept 12, at Sanders Theatre at Harvard. And join us on Sept 13 at Kendall SquareforPG-Palooza – a hands-on, brains-on labs day!
Other speakers include Ed Boyden, Co-Director of MIT Center for Neurobiological Engineering; and, Dr. Jordan Smoller, Professor of Psychiatry at HMS, whose research focuses on identifying genetic determinants of childhood and adult psychiatric disorders.