Remote Control With An XBee And A Propeller

If you’ve been playing with electronics for long enough, eventually you’ll need a nice remote control transmitter to control your RC car, airplane, or any other robotics project you have lying around. With these robotics projects comes the problem remote control, and the XBee Handheld Controller may be just the ticket to remotely control any project that comes off your workbench.

This isn’t the first remote controller we’ve seen that does just about everything, but it is the first one to include an XBee wireless transceiver to easily interface to your robotics project. The controller comes in two models, the Q4, which uses four Playstation-like joysticks, and the Q2, which uses proper remote control gimbal joysticks. Both the controllers have a slew of buttons, toggle switches, four rotary pots and a 2×20 LCD display.

After the break you can check out [Paul]’s pitch explaining what these controllers can do and showing off a hexapod robot under the control of his Q4 controller. A very neat project, and we can’t wait to see this controller out in the field.

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Teaching A Computer To Learn

[Łukasz Kaiser] programmed a computer to play Tic-tac-toe. That doesn’t sound very remarkable until you realize he never told his computer the rules of Tic-tac-toe. The computer learned the rules by itself after watching a video of two people playing the game (link to actual paper – PDF warning).

[Łukasz] wrote a small program in C++ to recognize the placement of objects on a Tic-tac-toe, Connect 4, and Breakthough board. This program sifts through winning and losing games along with illegal moves to generate a Lambda calculus-like rule set for the relevant game. Even though [Łukasz] has only programmed a computer to learn simple games such as Tic-tac-toe, Connect 4, and Breakthrough, he plans to move up to more complex games such as Chess.

The fact that [Łukasz] programmed a computer to actually learn the rules of a game gives us pause; in one of the fabulous lectures [Richard Feynman] gave to freshman physics students in 1964, the subject of Chess came up. [Feynman] drew parallels between learning Chess and performing research. Every move is hypothesis testing, and when a very strange move occurs – castling, en passant, and the promotion of a pawn, for instance – the theory of the rules of the game must be reworked. Likewise, when extremely strange stuff happens in physics – particle/wave duality, and the existence of black holes – scientific theory is advanced.

Yes, teaching a computer to learn the rules of Tic-tac-toe may seem irrelevant, but given the same learning process can be applied to other fields such as medicine, economics, and just about every science, it’s not hard to see how cool [Łukasz]’ work is.

via extremetech

Ouya, A $100 Game Console For Indie Developers

With the explosion of mobile gaming (due in no small part to the egg-bombing Angry Birds), the Ouya was bound to happen. It’s a $100 game console powered by Android that puts indie games right into your living room.

The specs for the Ouya means this cube of games isn’t a slouch: the console comes loaded with an NVIDIA Terga3 quad-core processor, 1 GB of RAM, 8 Gigs of flash storage, HDMI, WiFi, Bluetooth, and Android 4.0. A requirement for publishing games on the Ouya is making at least some of the game free to play, a la TF2 or LoL. In addition to being a video game console, Ouya will also pull down Twitch.TV streams allowing you to watch Starcraft championships and other e-sports on your big-screen TV.

Not only does the Ouya play games, its designers made the device easily hackable. There aren’t enough details to know exactly what this means, but we’re sure we’ll see a full-blown Linux distro running on the Ouya within a week of release.

As of this writing, the Ouya Kickstarter has already met their funding goal of $950,000 by taking in two million a freaking ton of money with 29 days left. This might become the most successful Kickstarter to date, and we can’t wait to see all the neat stuff and hacks for the Ouya in the near future.

BlinkM Gets Upgraded To A USB Mass-market Device

[TodBot] has a new piece of hardware on the way up. His Blink(1) is currently about 50% funded on Kickstarter. It’s a USB nub that has an RGB LED inside of it. When plugged into a computer it can be used as a status indicator. At first that sounds like a let down, but his marketing is fantastic as the myriad of uses really caught our attention. If you’re on the road you can use it to report back your server statistic. Plug one into each rack-mounted servers for quick visual indication of which one has crashed. Or find your own use.

You probably remember [TodBot] as the creator of the BlinkM. Recently he was calling it the world’s smallest Arduino. Well this Blink(1) is being marketed as Arduino programmable as well. The board size is about the same, and both have an RGB LED module. The difference is that the BlinkM had an ATtiny85 and needed a serial converter to program it. This has a USB plug so we’d bet he’s swapped the tiny for an ATmega8u2 or something from the same family.

Don’t think one blinky LED is going to cut it? For folks that just need more resolution there are other hardware options out there. For instance, this project gives you a wireless 8×8 RGB led display to use as an indicator.

Playing Footsie With Your Video Games

[Jon] will be tapping away with his toes during gaming session thanks to this foot controller which is packed with buttons and sensors. It’s the second iteration of the build. The original had some solder joints break and the USB stopped working. He had also been experiencing some erratic behavior and so he decided to upgrade the control hardware and add a few more things in the process.

This version uses an Arduino Uno as the interface board. He did a bunch of prototyping to find the best way to hook up all the analog sensors, and how to properly debounce the buttons. Once he was happy with the inputs he set about finding a better way to use the USB HID standard with the device. We were surprised to hear that the ATmega16u2 (one of the new AVR chips which includes USB hardware) doesn’t play nicely with Linux. But [Jon] managed to hack his way around that issue and now he’s gaming with an even better foot controller than before.

Time-based One-Time Passwords With An Arduino

Get your feet wet with Time-based One-Time Password (TOTP) security by building your own Arduino OATH system. OATH is an open standard authentication system that provides a platform to generate tokens, making your login more secure than a password alone would.

The TOTP approach is what is used with many companies that issue hardware-based dongles for logging in remotely. This security may have been compromised but it’s still better than passwords alone. Plus, if you’re building it around an Arduino we’d bet you’re just trying to learn and not actually responsible for protecting industrial or state secrets.

The hardware setup requires nothing more than the Arduino board with one button and a screen as a user interface. Since the board has a crystal oscillator it keeps fairly accurate time (as long as it remains powered). It will push out a new token every thirty seconds. The video after the break shows that the Arduino-calculated value does indeed match what the test box is displaying.

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