All posts by Lenore Edman

About Lenore Edman

Co-founder of Evil Mad Scientist Laboratories.

A template for BristleBot Competitions

Aesthetically Interesting

For the robotics team that we mentor (FRC team 3501), we created an “Advanced Bristlebot Competition” to serve as an off-season team building exercise. We are publishing our competition template (PDF download) here so that anyone can use it as a starting point for their own events. The goals of the competition are to provide a self-contained, resource-constrained and time-limited introduction to a robot competition environment, and to get new and continuing students working together on solving simple engineering challenges.

Arenas

The competition consists of three challenges: sprint (distance time trial), mountain climbing (same, on an inclined plane), and sumo (a two-robot competition that rewards going in circles).

Working together

The group of students is split into teams of two, trying to pair new students with team veterans.

Distributing supplies

Each team is given a set of rules and a small pile of toothbrushes, motors, and batteries.

construction supplies

Beyond this, one table is designated for tools and supplies, and has an assortment of craft supplies including things like coffee stir sticks, wires, twist-ties, googly eyes, pipe cleaners, pom-poms, and tape. Building tools include hot glue guns, scissors, bolt cutters (for cutting the heads off of toothbrushes), and wire strippers.

Ready for competition

After a building period, the robots are “bagged and tagged” prior to competition. For the BristleBots, this means they are placed on paper plates marked with their team number for inspection to ensure that they meet the competition requirements.

Practice match

The competition takes place in two rounds, separated by an interval of building time between them.  The extra time allows the students to redesign and implement changes based on what they learned during the first round of matches.

Vrooom...

We witnessed a couple of great moments during our event. We overheard some students watching our original BristleBot video on a phone, and when they noticed us watching them, they defended themselves, saying, “The rules don’t say we can’t!”

Go!

One of the most technically inclined students on the team, after building several prototypes and studying the performance of his BristleBots on the ramp for about 10 minutes asked, “This can’t actually be done, can it?” Minutes later, a veteran student from another team, proudly set his robot on the ramp and it whizzed up in one solid go in about 10 seconds. Later, during competition, another student watched her BristleBot zoom up the ramp in 3 seconds flat, using a variation on that successful design.

Materials & Resources

A Flavor Exploration Kit

Untitled

There are culturally common activities like wine and cheese tastings that explore variations of a particular theme. There are also flavor tripping parties specifically for trying out the taste bud altering miracle fruit. And there are molecular gastronomy and modernist cuisine that are intended challenge your expectations of texture and flavor. In the spirit of these kinds of experiences, we came up with a wide-ranging set of interesting (and sometimes challenging) items that can be shipped through the mail and shared between internet friends.

The goals of the project include isolating a few interesting flavors that are not normally tasted on their own, understanding a bit about the ways that shape and texture affect flavor, and play a bit with some of the available “mouth altering” spices and flavors.

Most of the items we included in our tasting kit are from Indian or asian grocery stores. For herbs and spices, getting them from a shop with high turnover will help in obtaining fresher spices that are more full of flavor. They’re also likely to be less expensive at places that expect larger quantities of spices to be used in foods (we’ve written about this before). Ethnic groceries are better at this than mainstream ones, and places with bulk bins can be just about the worst. A few items we shopped for online, and a couple came from our garden.

For tasting order, we opted to start with more subtle flavors and end with mouth-altering ones. Our general itinerary was divided into four parts: flavors & scents, shapes, adventures, and light.

Of special note: many people are sensitive to particular (and sometimes esoteric) food items. Be sure you have discussed food allergies with all participants before plying them with unknown ingredients. Decide if you want to try things before announcing what they are. Have water and neutral flavored crackers or bread for cleansing the palette between flavors as needed or desired.

One of the joys of life is introducing people to new flavors and textures that you love, whether they are from your own kitchen or your favorite restaurant. Every so often, that will backfire, when someone ends up not liking your beloved dish. But sometimes you’ll see that “eureka” moment when someone lights up from the new experience. Eating involves many kinds of sense perception, including smell, taste, texture, temperature, and sight.

 

Part one: Flavors & Scents

  • Fenugreek Leaf (Methi): fenugreek has an aroma reminiscent of maple syrup and is one of the magic ingredients in tandoori marinades. Crumbling dry herbs in your fingers will help release aromas.
Makrut (Thai) Lime Leaves
Makrut (Thai) Lime Leaves
  • Makrut (Thai) Lime Leaf: a crucial ingredient in many Thai curry pastes and soups. This double-lobed citrus leaf is available fresh at many asian groceries, and we’ve written about it before.
  • Curry Leaf: used in south Indian cuisine, such as the soups you find at dosa shops. We have a little curry tree, but leaves can be obtained fresh at Indian groceries.
  • Ajwain: spicy, somewhat reminiscent of thyme or oregano. Also from Indian cuisines and spice blends.
saffron
Saffron Threads
  • Saffron: always used in very small amounts due to its potency and expense. Almost never tasted alone.
  • Chat (Chaat) Masala: used primarily on Indian snack foods. Key spices include black salt, mango powder, cumin and asafoetida. Try it on some fresh fruit.
  • Black Salt: very sulfurous pink colored salt mined from the Himalayas.
  • Truffle Salt: an excellent way to experience the heady aroma of truffles. Try sprinkling it on vanilla ice cream.

 

Part two: Shapes

Sugar crystals
Sugar Crystals
Salt hopper crystals
Salt Hopper Crystals

 

  • Sugar Crystals: these large (~1/4 inch) sugar crystals are available at Indian and middle-eastern markets, sometimes labeled as “sugar cubes” despite their elegant shapes. They don’t seem as sweet as granulated sugar because of the low surface area to volume ratio.
  • Salt Flakes (hopper crystals): because of the huge surface area, these taste even saltier than granulated salt. Great for when you want to have lots of salt flavor and are sprinkling on a surface that will not dissolve the salt. Trader Joe’s is selling small containers with huge crystals. Alternately, Maldon Sea Salt Flakes are large enough to see the crystal structure.

    pepper threads
    Shredded Dried Red Pepper
  • Shredded Red Pepper: we came across these dried pepper threads at a Korean grocery store and have been garnishing our soups with them ever since. They’re preserved with salt and rehydrate to show the cross section from the center of the fruit to the skin.They’re beautiful and spicy, but not as spicy as red pepper powder because of the difference in surface area.

 

Part three: Adventures

sichuan pepper
Sichuan Peppercorns
citric acid granules
Citric Acid Granules

 

  • Citric Acid: we found large granules of this at an Indian market. One big granule is enough to make just about anyone pucker. This is the full-strength version of the powder that is used to make sour candies sour.
  • Sichuan Pepper (Prickly Ash, Wild Peppercorn): one of the components (hydroxy-alpha-sanshool) triggers an anesthetic reaction. After chewing on a couple of these husks, your tongue will go numb and tingly. It increases your ability to eat super spicy foods, and has been described to us as “a party in your mouth.” We’ve also seen very panicked faces of people who just wanted the sensation to stop. Some people don’t seem to be as sensitive to it, or perhaps didn’t get very active pieces, and they usually find the lemony flavor to be pleasant.
super soda gum
Super Soda Gum
miracle fruit tablets
Miracle Fruit Tables

 

  • Super Soda Gum: we discovered this great bubble gum through the Candy Japan subscription service and we now purchase it at our local Japanese grocery store. It has a powerful punch of fizzy powder inside, which makes your mouth foam up like crazy. It is awesome good fun, and it seemed to help the sichuan pepper effect to subside. Even after the excitement from the foam settles down, it is really good quality gum.
  • Miracle Fruit Tablets: we got these tablets from Amazon. They’re a little bit expensive, but the miraculin binds to sweet receptors on the tongue, making sour foods seem sweet. The berries are also available, but are more expensive, and harder to get shipped.
  • Citric Acid (again): after dosing with the miracle fruit, citric acid tastes like candy. Be careful, or you’ll inadvertently eat a lot of highly acidic food because it is so fun. Try other sour foods like lemon, lime, grapefruit, vinegar, and tamarind.

Part four: Light

  • Wint-O-Green Lifesavers: sugar crystals are a triboluminescent material, meaning that when you crush them, they emit light. However, they emit ultraviolet light, and so we don’t normally get to see the effect. Wintergreen oil fluoresces blue, so eating wintergreen flavored candies in the dark in front of a mirror or with friends will let you see it. Go into a very dark room. Wait until your eyes are accustomed to the dark. Bite the mints with your teeth to crack them to see the glow.

Other possibilities

  • Asafoetida (Hing): a very powerful garlic and onion substitute from Indian cuisine.
  • Seaweed: for someone who hasn’t been exposed to the flavor of dried seaweed, it can be a shock.
  • Dried Sumac: a sour fruit used in the spice blend za’atar along with sesame seeds and dried herbs.
  • Tamarind: a sour fruit that is less well known in mainstream American cuisine, but can be found in many familiar sauces (even some Worcestershire sauces). Commonly available as a paste or as pulp.
  • Other less common fruits, such as dragon fruit, soursop, jackfruit, and durian.
  • Fresh vs. freeze dried vs. canned textures and flavors.
  • From our group came the suggestion to create a flavor symphony, walking through various movements of flavor rather than isolating each one. It could be interesting to add more familiar herbs like mint, thyme, and rosemary to the mix.

Untitled
An exploration like this is fairly simple to lead when everyone is in the same place, but can also be done remotely. We packaged up our ingredients into little bags and tucked them into plastic organizer boxes (commonly available from the dollar store) to conceal the contents until the right moment.

The list above is strongly influenced by our personal experiences and cooking preferences. Depending on your background, things we find exotic may seem perfectly normal. It is interesting to see which ingredients stir up memories from the participants, and which are new to them as well. If you come up with other ideas, we’d love to hear about them!

Editor’s note April 10, 2021: This article has been edited to remove the word kaffir, which is offensive. Makrut is the preferred name for the fruit, which is also called Thai lime.

Photos: Silicon Valley STEAM Festival

mobile shark tank

Here are a few of our favorite pictures from the Silicon Valley STEAM Festival today. Above, a mobile shark tank from the San Francisco Bay Marine Science Institute.

Put the engine where?

One of the interesting aircraft on display.

Electric Car Corral

Some of the many electric cars.

Carpet treads for rover

Space-rated carpet treads on a mini-lunar rover to help it get traction in loose dust.

TechShop San Jose Young Makers Lotus

A Lotus from TechShop San Jose with a Young Makers banner on the windshield.

You can check out the full set of pictures on flickr.

KQED on Extreme Learners

Redhead with backpack looking at San Francisco skyline
By Jane Mount/MindShift

I recently talked to Linda Flanagan from KQED‘s blog on learning, MindShift, about extreme learning and her post What Makes an ‘Extreme Learner’? went up today.

It’s the hunger for learning rather than raw intellect that distinguishes Extreme Learners from the gifted. Intensely motivated and harboring a breadth of interests, they also consider ignorance a temporary and reparable condition.

I previously posted about the extreme learning workshop at the Institute for the Future.

From the mailbag: Fun soldering

Eric wrote in to say:

It was fun. It was fun to build the Larson Scanner. It was fun because I successfully put it together and it worked as designed. It was so fun I’ll do this again!

In the mid 70’s I attempted to construct a Radio Shack short wave radio kit with a soldering gun. That’s right, I used a soldering gun. Believe it or not, it worked … as a battery heater upper.

Thank you for the helpful instructions and well designed kit. It’s nice to know that 40 years after my last kit, I can drop the battery killer nickname.

The Power of the Digi-Comp II

Last fall, we built an oversized Digi-Comp II for MIT, which we’ll be posting about in the near future. Today, MIT computer science professor Scott Aaronson published a short “paperlet” about the computational capabilities of the Digi-Comp II on his blog, Shtetl-Optimized:

…it’s amazing that such a simple contraption of balls and toggles could already take us over the threshold of universality.  Universality would immediately explain why the Digi-Comp is capable of multiplication, division, sorting, and so on.  If, on the other hand, we don’t have universality, that too is extremely interesting—for we’d then face the challenge of explaining how the Digi-Comp can do so many things without being universal.

Pen tests for drawing machines

Jenslabs has published a thoughtful and thorough evaluation of a number of currently available rollerball and gel pens. He tested them using his Circlon machine.

One thing that anyone who as ever built a drawing machine realizes, is that to get quality results you need a quality pen. There are millions of pens out there, but after a little trial and error I realized that rollerball pens or pens with gel ink are the best pen types for my machine. Both rollerball and gel ink pens use a water based ink that is less viscous then the oil based ink used in ballpoint pens. The Circlon machine sometimes move very fast, so the pen has to be able to release enough ink to make solid lines even at high speed.

This is an excellent resource for folks with other drawing machines, such as Egg-Bots and WaterColorBots. We’ve linked to it from our page about choosing pens for the Egg-Bot as well.