Robotics Dev Kit for Kids

Background

If you read my other posts you'll know that I enjoy doing engineering projects with my kids. At home and at school they have played with some basic coding programs. My oldest son and daughter both expressed interest in programming as a hobby; my daughter is interested in astronomy, and my son is interested in robotics. They've played with scratch at school and dabbled in code academy. They have both lamented that the step between the kid programming games and real programming is too big and wish they had better stepping stones.

In a totally separate channel, I was riding on the train and thinking about introducing children to technology in ways that will KEEP them interested and engaged as they continue to grow.

From these two thoughts I wished that there was a robotics kit geared for kids that would provide a fun way to learn the basics of programming, but also incrementally unwrap the graphical programming methods to help them learn the underlying code structures.

The Idea

A robotics kit for kids with modular, easily connectable components and a coding interface that provides varying levels of difficulty.

Regarding the connectable components, I think Lego Power Functions is a perfect example of electronics that have pre-defined functions and can be built however you want right out of the box. They just work and don't take tons of soldering or programming to make something work. But Power Functions fall short when it comes to altering the behavior of the modular components. I think this is an essential part of programming robotics.

You might think that Lego Mindstorms is the answer. When I first had this idea, the answer was a definite NO. In my opinion the programming interface had a high learning-curve for younger kids. I think it is much better now, but the next strike against Mindstorms is the price point. I just think the $200-$400 price point for a single kit is too high of an entry point for most families who want to pursue this as a hobby, and whose kids may end up being not so interested.

As far as the programming interface, I really like the approach taken by the Scratch team. My kids have used it for silly projects and found it enjoyable. But they never learned how to dig into the code that underlies the little building blocks. So this robotics dev kit would provide that functionality to let them learn progressively more involved coding while learning how to control different properties of motors and sensors.

Progress

Has it Been Done Before?

Let me just say that we live in an amazing time in history. I love that people like me can have ideas,  share them publicly, and get the support from their peers to release a product to market, nearly risk free. And there are so many smart people who recognize a need and are willing to take various approaches to provide a solution.

There are some great options out there now that I would consider buying. If you combined the best features of the three below kits then you would obtain my ideal product!

1) Root Robotics

What is it?

• A pre-built robot with controllable behaviors and a programming interface with increment difficulty.

Pros

• Easy to use
• Fun
• Three levels of programming difficulty
• Teaches real programming
• Multiple programming languages
• Good for educators

Cons

• Limited ability to customize hardware
• Best used on a large whiteboard

2) Mabot

What is it?

• A plug-and-play, programmable robot.

Pros

• Modular components can be hot-swapped
• Plug and play
• Simple programming interface
• Compatible with Legos
• Expandable
• Good for young kids

Cons

• Full functionality requires a tablet
• Proprietary, limited programming interface

3) ROKit Smart

What is it?

• A robotics kit based on the Arduino development board.

Pros

• Standard electronics platform means nearly limitless expansion potential
• Teaches full-fledged robotics programming on Arduino
• Online lessons provide varying difficulty and project examples
• Good for older youth

Cons

• Programming interface requires installation and configuration
• No graphical programming for younger audience
• Not plug-and-play. Requires advanced ability to read and follow directions or an experienced teacher.

Water Jouncers

Background

I really have no idea why I thought of this. The kids woke me up early and I couldn't fall back to sleep. While laying in bed this morning I got a bunch of ideas. My brain is a single-thread processor. It's like a railroad track but there are a million switches. I think along one thread, sometimes detouring on tangents, evaluating ideas more deeply or completely switching directions on a new but related thought. I often backtrack and take different switches that I marked as interesting along the way. Conversations are like this. Jenn and I sometimes find it fun to trace conversations backwards and see all the different switch points.

Anyways, I'm sure there was some half-logical track that got me onto running across the water.

The Idea

A stilt contraption that displaces water allowing you to run across a water surface. First solve the mechanics of water displacement and find workable human input scenarios. One possible answer is to displace lager surface area like a lizard. Problem is with retraction speed. Evaluate an artificial webbed foot that expands on contract, putting force into springs. Then upon contraction the springs pull the webbing in and propel the foot out of the hole of displaced water. Or maybe the actual foot never enters the hole. Maybe it's only the mechanical device goes into the pocket, and the springs pull it out again, reset by the force of every step.

Progress

11/27/2014

Lizard that can run on water

Robot that can run on water

Just for Fun:

Fake but Fun

Jeff's Miracle Boots

No-Boat Water Skis

Background

The Aquaskipper has proven that human power can propel a person above the water using hydro foils. People have attempted self-propelled water skis in the past, but the designs were all horrible. The Mythbusters' Adam Savage tried a typical approach of floating pontoons with flaps for propulsion. They turned out to be unstable and not mobile. What we need a good, functional design.

The Idea

I need to sit down and determine the physics required to keep a person on top of the water using a combination of buoyancy and propulsion. Then I need to explore the design space around these two factors and design water skis that operate similar to the principals used in the Aquaskipper. In my mind I envision something like cross-country skis for water. Cross-water skis?

Progress

11/27/2014:

A Purely Buoyant Solution - Archimedes' Principle

Put simply, the buoyant force on a submerged object is equal to the weight of displaced water. For a purely buoyant design this means displacing enough water to hold up a person. Assuming a weight of 80 kg (roughly the average American male) at standard temperature and pressure, this means displacing approximately 80 liters of water. Sounds like a large volume, but that equates to two skis that are 25 cm wide, 10 cm deep and 160 cm long. So I guess Adam Savage had it about right with his big dorky skis (for the record I was rooting FOR him).

In my opinion this is the worst way to design these skis. This is the maximum footprint of a workable design, so we should be able to stay well below that size by requiring the person to move to stay afloat. More like the Auqaskipper which uses little buoyant force.

A Purely Dynamic Solution - Barefoot Skiing

A rule of thumb for barefoot skiing speeds says take your weight in pounds, divide by two and add 20 miles per hour. This gives around 37.5 mph or 60 kph. That's really fast. The Aquaskipper obviously goes much slower than that. I found a paper on water skiing biomechanics that showed a chart of rope load that was half the skier's weight while going 15 kph.

Hardware Device to Make a DVD Player Act Like a Hard Drive

Background

I'm always in the pursuit to maximize the utility and convenience of my Home Theater PC (HTPC). For me this means finding a balance between cost, performance, footprint and versatility. I want to be able to play DVDs, watch Netflix, YouTube and possibly even some light gaming. This is all available on a Windows platform, but that comes with the cost of a Windows license and the hardware to keep up with Windows bloat. I've tried Linux, but it just doesn't support Netflix reliably. Android has everything except DVD support. There are some new Android mini PCs that would work great if I could just find a compatible DVD player.

While searching for DVD drives I found other people who want to access DVDs on other devices. It seems that hard drives will work on EVERYTHING...TVs, phones, tablets, computers, etc. Why can't DVDs have the same support?!

The Idea

We could solve everyone's DVD problems by creating a hardware device sits between the DVD player and the computer / TV / android device. The device would read the DVD player but make it look like a hard drive to the computer.

I know that this device is 100% possible. In the worst case scenario the device is a mini computer that plays the DVD and transcodes it into an MPEG file. I guess basically a hardware transcoder. That's not cost effective. To be cost effective it would have to operate on a very low level, reading the DVD to see what options are available, then present them as a limited set of files on a hard drive, each file name representing a different set of movie options.

I think the biggest hurdle is solving the problem at the file transfer level. You have to present files that are readable by the computer, which for really stupid devices means video and audio files. Dumb devices only know how to read different file formats, so how do you convert the request for a byte stream into a DVD read? It may not be possible to get that low. Maybe transcoding is the closest you can get.

Progress

 11/27/14 -I really don't have the background to research this device right now, and I'm not interested in learning that low level programming, so this idea is gonna sit on the shelf, probably forever.

Automated Home Library

The Idea

Tonight Jenn and I were talking about what we should do with the spare bedroom. We just moved our two-year-old out of the crib and into a twin, sharing a room with her older sister. We could buy another bed and turn it back into a guest bedroom. We could turn it into extra storage space, or expand our office and scrap-booking space. I've always liked the idea of a library or reading room where the kids could sit and read. But it's only the idea that's nice. In practice the kids pull all the books off the shelves and onto the floor. So talked about different ways to store the books or limit access to keep things somewhat controlled so we can avoid the hassle of getting them to clean-up everyday. I mean, if there's something we DON'T need it's another room to clean.

I'm a process engineer with training in lean manufacturing. I spend a great deal of time at work cleaning up messes, self-induced or otherwise. To avoid future methods we use a method called poka-yoke, which is Japanese for mistake-proofing (literally yokeru=avoid poka="inadvertent error").

So we thought, maybe we keep the books in boxes, but label the boxes so we can easily find the books. Then we can control access and avoid the mess. But the problem becomes awareness. We forget which books we have, and if the kids can't see them, then the kids won't ask to read them. We could catalog the books and have a list. Even better if there were pictures too. Maybe in a computer so it could be easily searched or sorted. Yeah, now we're literally building a library.

So I thought, how cool would it literally build a library. I don't want to staff it...maybe I could have a robot do all the work. Let's take the room and turn it into a Redbox-style machine with a computer interface. The books would all be stored in custom shelving - horizontal slots with barcodes. The kids could pick a book from the catalog and the robot would go get the book and send it through a slot in the door. The robot would run on a track and get instructions from the computer on where to get and store each book. Then I could limit access to two books per child. They gotta return a book before they can get any more. Redbox style...just put it in the slot and the computer / robot puts it away.

Progress

I really like this idea, but I don't want to totally dedicate that room. It would be a cool "look what I can do" project, but I don't know that I'll ever pull the trigger. Sometimes it's just fun to know that I could actually do that.

Whiteboard Alternative

The Idea

I work in the semiconductor industry, and nearly everyone has a whiteboard in their cubicle to assist the many discussion we have about equipment, processes, statistics, etc. Whiteboards are a cheap, effective, and relatively clean alternative to projectors, blackboards, etc. But they still require consumables, and they're not totally clean.

For a while I've been wanting to see if I could develop a better alternative. It would be nice if I could improve cost and invent something manufacturable and marketable, but at the very least it would be fun to have something unique for me to use.

Progress

Giant "Magna Doodle"

This would be a 3'x4' Magna Doodle board. Magna Doodles use an opaque ferrofluid trapped inside small cells. When a magnet is touched to the surface, the iron particles in the fluid come to the surface creating dark spots / pixels.

Pros:

• No mess
• No consumables
• Variety of cheap magnets

Cons:

• Poor resolution
• Monochrome
• Wears out with use
• Expensive to piece together or custom build one large sheet
• Hard to erase just one small section

Magnetic Viewing Film

 Viewing film operates on a similar principle as the magnadoodle, but the fluid cells are much smaller, and typically green. I've never played with it in person, I should buy a sample to see how well it would work.

Pros:

• No mess
• No consumables
• High Resolution
• Variety of cheap magnets

Cons:

• Monochrome
• Slow response?
• Have to piece multiple sheets
• Hard to erase just one small section?
• Fragile 

8/9/2014 - I got my viewing film last week, just a small sample. It's really fun to play with, but the difficulties in using it for drawing became quite clear. The film is plenty responsive; it's too responsive. It can produce decent contrast, but when you pull a permanent magnet away the contrast changes as the fields move through the film. Wherever you start and stop a line will look blurry. You'd have to use an electromagnet that activates when you touch the surface. That's doable, but more hassle. The last drawback is with erasing. You have to hit the entire board with a uniform field from the backside. That's just a little too much bulk and complexity for me to mess with right now. 

E-Ink

 E-Ink is a new technology used in some e-readers. Instead of using a ferrofluid, electronic ink puts a dark ink/oil inside the microcavities along with charged, white particles. The microcavities are coated top and bottom with a conductive film. Applying a charge to the film can move the white balls to the top or the bottom to provide pixels and contrast.

Pros:

• High resolution
• Long life
• Robust housing
• Multiple colors possible.

Cons:

• Requires electricity (could use manual generation)
• Micro-fabrication is expensive and difficult

This is my favorite method. I would like to learn how they manufacture these displays so I could make one of my own. I emailed the company to see if they would sell me a batch of ink that I could put on my own surface. Of course I got no response.

Giant BoogieBoard

The BoogieBoard is an LCD display that does not require power to retain an image. It uses chiral liquid crystals to form a cholesteric, bi-stable display. The crystals are oriented in parallel planes which align in a cork-screw fashion. Within each plane the crystals lie flat, aligned uni-directionally. This crystal medium will selectively reflect light depending on crystal orientation. I found the actual manufacturing process in a whitepaper written by Kent Displays. I have enough information on this idea to actually try building a device.

Micro Magnet Array

Giant grid of magnets with poles all in the same orientation. Pull forward or push back. Same principle as magna doodle only with magnets instead of iron. Magnest would have to be small enough and far enough apart to reduce their influence on each other, and that will limit resolution.

Dirt Drawing / Sand Writing

Writing in dirt may be the oldest form of written communication. For this project I'd use sand. I'm sure there are several ways this concept could be realized. You could have a tray of sand and use it like they do in the high contrast, flat sand art. Or you could have a packed surface using etched lines. I would need to think of a good way to make a vertical unit. It would be heavy.

Generalizing the Principles

Okay, now that I've gone through a few different ideas I think I can start distilling the underlying principles by which these devices operate. Basically you are creating contrast between a background medium by adding or moving another material. The forces being applied are electric, electrostatic, magnetic, and direct physical contact. If the background medium is liquid, and the secondary material can diffuse in the medium then the secondary material must be physically isolated to keep it evenly dispersed. If the secondary material can freely move, then you must deal with a mess or have a recycling method.

Types of Forces:

• Applied
• Direct
• Pneumatic
• Hydrolic
• Friction
• Spring
• Gravity
• Electromagnetic
• Electrostatic
• Magnetism
• Nuclear

Fashion Consultant App

Okay, so I am fashion impaired. I have a terrible time picking out what to wear just from the limited wardrobe I already own, and an even worse time trying to select new clothes. I don't really want to do all the reading required to teach myself how to dress so as to not be an eyesore. Socks and sandals? Who CARES?

Tonight Jenn is asking about what clothes I need. She showed me some shorts and asked which ones looked nice. "I don't even know where to start."

Then it hit me. I need an app to help me dress, and to help me pick out new clothes. At the very basic level I need to be able to input my wardrobe and have the app tell me good combinations for outfits, tell me what I'm missing to make some good combos, and give me advice on what to buy. It needs to integrate with the camera so I can take pictures of the articles of clothing (of course there needs to be a simple camera color calibration). Clothing recognition would be nice, but I've done some coding work on that and it's pretty tough.

Then next time Jenn asks me what I think about a pair of shorts I can just take a picture and have my expert consultant tell me how it fits into my wardrobe.

Maybe you could take it to the next level and take a picture of yourself and have it recommend styles of clothing for you.

Could you really distill a fashion consultant into an app? Maybe not high fashion, but to get an engineer dressed appropriately I think some fashion basics knowledge would be quite feasible.

TV Screen Protector

I did this project years ago. It's a cheap way to protect your big-screen TV from flying objects (toys specifically). I just recently got the motivation to start sharing past projects, so I wrote an Instructable.
TV-Screen-Protector via Instructables

Update 7/9/14: Yay! I guess they liked my project enough to feature it on the homepage! It's kind of addicting to get positive feedback. Now I'm wondering what else I can make and publish.

Non-Insulating Weight Blanket

The Idea

When I sleep I like to have a medium to heavy weight blanket on me. I'm also a little quirky because I also need to cover as much skin as possible, so I typically sleep with socks, long pants and long sleeves. On warm nights I obviously get too hot with all that insulation, so I have to toss the blanket and/or the clothes. This makes it more difficult for me to get a good night's sleep. I'm sure I could learn to live without all my securities, but I like to increase my quality of life when it's convenient. Some people grew up in more difficult circumstances where such securities are practically a necessity. These types of dependencies are commonly tied to autism and Down's syndrome. I identify with people on the spectrum and often suspect and joke that I, myself, am on the spectrum. I've remember one parent's story about how their high needs child would come home at the end of the school day and burrow into a pile of blankets to recover from the unpredictable social jungle that is called Junior High. So I've thought to myself, "Wouldn't it be nice to have the security without the added discomfort?" That's how I came up with my idea of the non-insulating weight blanket. It's a blanket of equivalent weight without the insulating properties. I want one of these blankets, but I can't find one sold anywhere, so I'm going to have to develop it myself.

 Progress

 My favorite blanket right now is a denim blanket made by my wife. It's about the perfect density and provides a secure level of pressure, but it probably falls on the lighter side of a good security blanket. It's 56 inches wide, 70 inches tall, and weighs 4.8 pounds. That's a pressure of 0.0012 psi (or 2.5 feet of air, 0.9 kg/m^3, 84 microbar, 8 pascal, etc.). I found some blankets made for people with sensory processing disorder. A blanket of similar size can be up to 25 pounds, but I think those are designed for temporary therapeutic relief and not meant to be used for an entire night. In any case it seems the acceptable range of pressure is fairly large.

Critical Ratio

My first inclination in such a design is to modify the thickness to possibly exploit the critical insulation ratio. When you insulate a round object the added insulation slows down conduction but speeds up convection. There is a critical insulation thickness such that when your insulation is below the thickness you speed up heat transfer by adding insulation. And when your insulation thickness is above critical adding insulation slows down heat transfer. So my first thought is to estimate the critical ratio for a blanket around a person.

Without going through a bunch of explanation (here's a good link for that) the critical ratio basically comes down to the rate of conduction vs the rate of convection, or k/h. I estimate the thermal conductivity (k) of a denim blanket to be around 0.04 W/m*K. Estimating the convection coefficient (h) is a little harder, but to just get in the very rough ball park let's think about a human body. The internal temp is 37 degrees C, and the room temp is 20C giving a delta of 17C (or Kelvins if you wanna be technical). Using a guess of 2 square meters of surface area, 80 Watts heat generation that gives around 2 W/m^2*K.

So that gives a critical radius of (0.04 W/m*K)/(2 W/m^2*K) = 2cm. So, um, you might be able to cool down a finger...but your whole body ain't gonna fit inside 2 centimeters.

Mesh and Material

If I can't win by changing the thickness of the blanket then I will have to remove some of the insulating material and turn the blanket into more of a mesh. That will cause a hit in density, so I'll have to modify the material composition to increase density. The ideal material would be thermally conductive, easy to wash, easy to sew or press, flexible and cheap.

Material	rho (gm/cm^3)	k (W/m*K)	Washable	Sew/Press	Flexible	Cost ($/lb)
Dirt / Earth
Polypropylene