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Vol. 6 No. 10 SSEERRVVOO MAGAZINEHUMANOID ROBOTS•PROPELLER•STARTER MOTORS•DIGITAL RF DATALINK Cover.qxd 9/4/2008 8:43 AM Page 1 Let your geek shine. Meet Pete Lewis, lead vocalist for the band Storytyme. Pete recently created the RS1000, a new personal monitor system for performing musicians. It was SparkFun’s tutorials, products and PCB service that enabled him to take his idea to market in less than a year. The tools are out there. Find the resources you need to let your geek shine too. ©2008 SparkFun Electronics, Inc. All rights reserved. Hear music from Storytyme at www.storytymeband.com, or check out Pete’s RS1000 at www.rockonaudio.com. Sharing Ingenuity WWW.SPARKFUN.COM Full Page.qxd 7/9/2008 9:57 AM Page 2 email: sales@crustcrawler.com Full Page.qxd 9/3/2008 12:24 PM Page 3 Features 22 BUILD REPORT: Savage — Part 1 24 MANUFACTURING: Combat Robot Drive Systems 27 Building Battery Packs Fit for Combat 31 PARTS IS PARTS: Electronize Speed Controllers Events 26 Results and Upcoming Competitions 32 Event Report: Roaming Robots Goes to Qatar Robot Profile 30 K2 SERVO Magazine (ISSN 1546-0592/CDN Pub Agree#40702530) is published monthly for $24.95 per year by T & L Publications, Inc., 430 Princeland Court, Corona, CA 92879. PERIODICALS POSTAGE PAID AT CORONA, CA AND AT ADDITION- AL ENTRY MAILING OFFICES. POSTMASTER: Send address changes to SERVO Magazine, P.O. Box 15277, North Hollywood, CA 91615 or Station A, P.O. Box 54,Windsor ON N9A 6J5; cpcreturns@servomagazine.com 06 Mind/Iron 18 New Products 19 Robotics Showcase 20 Events Calendar 66 Robo-Links 67 SERVO Webstore 81 Advertiser’s Index Columns 08 Robytes by Jeff Eckert Stimulating Robot Tidbits 10 GeerHead by David Geer Robot250 Features BigBots 13 Ask Mr. Roboto by Dennis Clark Your Problems Solved Here 70 BasicBoard Robotics by William Smith Hardware Serial Port Adapter 73 Robotics Resources by Gordon McComb Getting Kids into Robotics 76 Appetizer by Camp Peavy RoboMagellan 78 Then and Now by Tom Carroll Robots — From Humanoid to Human Status PAGE 78 PAGE 26 PAGE 10 4 SERVO 10.2008 THE COMBAT ZONE . Departments TOC Oct08.qxd 9/3/2008 1:40 PM Page 4 10.2008 VOL. 6 NO. 10 SERVO 10.2008 5 34 A Digital RF Datalink by Fred Eady When your robots need to communicate, but can’t see each other, short-distance signaling using low-power RF solves the problem. 40 Getting Control With the Propeller: Part 2 by David Carrier Controlling servos. 44 Get a Starter Motor Runnin’ in Your Robot by Steven Schmitt Auto star ter motors are often overlooked for use in robot building. However, they make a good choice for power since they are almost always series wound, inexpensive, and readily available. 49 Counting on the Tried and True Schmitt Trigger by Margaret Toebes See how one team at the North Carolina Science Olympiad put this classic circuit to work. 52 The Pico ITX Johnny 5 Project by Andrew Alter Part 2 covers the concept and implementation of PC- based robotics. 56 RoboGames 2008 by Samuel Coniglio This world class event continues to not disappoint year after year. 60 External Interface for the NXT Robotic Brick by Dennis Bogden Using Robot C software and integrated circuits, you can interface your own sensors and actuators to the NXT brick. PAGE 56 Features & Projects Due to extraterrestrial activity, the “Build the Ultimate Robot” series by Michael Simpson will continue in the November issue. We apologize for any inconvenience. TOC Oct08.qxd 9/3/2008 1:42 PM Page 5 Published Monthly By T & L Publications, Inc. 430 Princeland Ct., Corona, CA 92879-1300 (951) 371-8497 FAX (951) 371-3052 Webstore Only 1-800-783-4624 www.servomagazine.com Subscriptions Toll Free 1-877-525-2539 Outside US 1-818-487-4545 P.O. Box 15277, N. Hollywood, CA 91615 PUBLISHER Larry Lemieux publisher@servomagazine.com ASSOCIATE PUBLISHER/ VP OF SALES/MARKETING Robin Lemieux display@servomagazine.com EDITOR Bryan Bergeron techedit-servo@yahoo.com TECHNICAL EDITOR Dan Danknick dan@teamdelta.com CONTRIBUTING EDITORS Jeff Eckert Tom Carroll Gordon McComb David Geer Dennis Clark R. Steven Rainwater Fred Eady Kevin Berry Andrew Alter Dennis Bogden Sam Coniglio Margaret Toebes Steven Schmitt David Carrier James Baker Mike Jeffries Robert Wilburn Paul Reese William Smith Camp Peavy CIRCULATION DIRECTOR Tracy Kerley subscribe@servomagazine.com MARKETING COORDINATOR WEBSTORE Brian Kirkpatrick sales@servomagazine.com WEB CONTENT Michael Kaudze website@servomagazine.com PRODUCTION/GRAPHICS Shannon Lemieux Joe Keungmanivong ADMINISTRATIVE ASSISTANT Debbie Stauffacher Copyright 2008 by T & L Publications, Inc. All Rights Reserved All advertising is subject to publisher’s approval. We are not responsible for mistakes, misprints, or typographical errors. SERVO Magazine assumes no responsibility for the availability or condition of advertised items or for the honesty of the advertiser. The publisher makes no claims for the legality of any item advertised in SERVO.This is the sole responsibility of the advertiser.Advertisers and their agencies agree to indemnify and protect the publisher from any and all claims, action, or expense arising from advertising placed in SERVO. Please send all editorial correspondence, UPS, overnight mail, and artwork to: 430 Princeland Court, Corona, CA 92879. Size Matters W hen Parallax announced their new 12 VDC motors with mount, wheels, and position controller, I couldn’t resist picking up a kit ($280). Finally, a ‘standard’ drive system designed for medium-sized mobile robots from the company behind the BASIC Stamp and the Boe-Bot. The verdict? In short, the kit is first-class. Not only are the aluminum components beautifully machined and professionally finished, but the two 12 VDC motors are powerful and the gearing is aggressive — expect about 150 RPM at 1.5A and no load. Furthermore, assembly instructions and example Stamp source code are straightforward and easy to follow. It took me all of 20 minutes for basic assembly, including mounting the quadrature encoder assembly and inflating the pneumatic tires. I paired my motor kit with a pair of the recommended HB-25 controllers ($50 each) from Parallax. The controllers are hefty, with built-in heatsinks and cooling fans, and at less than three ounces, add little to the overall weight of about six pounds for the pair of motors. Is the kit perfect for every robotics application? Of course not — no general-purpose kit could be. For example, the pneumatic 6” tires; while well executed, are overkill for my needs (an indoor balancing bot platform) given their relatively small diameter and inherent stiffness. I replaced the inner tubes with zero maintenance foam tubing. It’s a trick I picked up from working with Traxx wheels. Want a stiffer, more supportive ride? Simply use denser foam inserts in the tires. Another consideration is ground clearance for the motor and motor mount. There’s only about an inch of clearance from the rectangular motor mount to the contact surface. This shouldn’t be a problem if your robot is going to be working on pavement, carpet, or even a mowed lawn. However, if you’re thinking of running your robot down gravel roads and rough terrain, you might want to consider protecting the Mind / Iron by Bryan Bergeron, Editor Mind/Iron Continued 6 SERVO 10.2008 Mind-IronOCT08.qxd 9/3/2008 2:58 PM Page 6 motors from accidental impact with a sheet of plastic or even a layer of electrical tape. If you’re thinking of moving from a Boe-Bot or other small mobile robot platform to something based on the Parallax wheel kit, take a moment to consider what’s involved. You’re not simply replacing small, inexpensive, lightweight servos with a heftier, more powerful (and more expensive) drive system; you’ll have to upgrade your entire development infrastructure. For starters, you’ll have to stock up on heavy duty aluminum stock — sheet metal, brackets, and fasteners. I’m not talking about the solid chassis designs used to create heavy-duty battle bots, but stock that’s significantly more substantial than the easily workable aluminum and plastic used with a typical carpet roamer. Then there’s the issue of power. Forget about using a AA battery pack. Instead, think 12V gell cell or — better yet — a pair of six-cell, 7.2V NiMh battery packs sold for R/C vehicles. I’ve had great results with the Dura Trax six-cell, 7.2V, 4.2 Ah pack ($43 each) available from Tower Hobbies (www.towerhobbies.com). While you’re on the Tower Hobbies website, pick up a few sets of two-pin Ultra Plugs by W.S. Deans ($3/set). Try these quick connect, low resistance plugs for your battery connections and you’ll never want to use a Molex connector again. Because of the mixed voltages required — 12 VDC for the Parallax motors or HB-25 motor controllers and 5V/3V for the microcontroller and sensors — you should consider a high-efficiency DC-DC converter. My favorite is the programmable, three-channel RGi Power Commander (($200), available from CrustCrawler (www.crustcrawler.com). I use it to convert the 14.4 VDC from a pair of NiMh battery packs to 12V, 5V, and 3V, to power the motors, sensors, and Parallax Propeller chip, respectively. Alternatively, you can use separate battery packs and dedicated voltage regulators for each voltage — but this wouldn’t be my first choice because of the additional weight and space requirements. You’ll also have to consider your tools. As noted above, you won’t be working exclusively with easily bendable aluminum, but you’ll have to learn to handle heavy-duty stock. And this means you’ll probably have to upgrade to heavy-duty tools — no more bending the aluminum chassis with needle-nose pliers. Think bench vise and rubber hammer. Given the added expense of a medium-sized robot over something that can fit in your hand, why make the move? For one, you can create something practical — a robot to fetch the paper, move a tray of food from one room to another, or bring your medicines when they’re prescribed, for example. You can also drop a laptop or even a computer motherboard on a medium-sized platform and have carrying capacity to spare. If you do decide to make the move — with or without the Parallax motors — drop me a line and a photo to share with your fellow readers. SV ISP programming connector push-on/push-off power button reset button piezo buzzer 30:1 micro metal gearmotors user pushbuttons removable 8x2 character LCD battery charger connector optional power LED 5 reflectance sensors on underside 4 AAA batteries (not included) * High-traction silicone tires * Speeds exceeding 3 ft/sec using innovative constant- voltage motor supply robot diameter is 3π cm (~3.7 inches) Item #975 $99.95 The Pololu 3pi robot is a high-performance, compact mobile platform featuring: * Two metal gearmotors * Five reflectance sensors * 8×2 character LCD * Three user pushbuttons * Buzzer and LEDs All peripherals are connected to an ATmega168 microcontroller running at 20 MHz, with free C-programming tools, libraries, and support for the Arduino environment. Find out more at www.pololu.com/3pi or by calling 1-877-7-POLOLU. SERVO 10.2008 7 Mind-IronOCT08.qxd 9/3/2008 2:59 PM Page 7 8 SERVO 10.2008 Fecundity Begets Rotundity If you tip over the average robot, all it can do is thrash around helplessly until someone picks it up. But being round and without external appendages, the Groundbot™ from Rotundus (www.rotundus.se) is always upright. It also can move through mud, snow, and sand without getting stuck, and, being hermetically sealed, is pretty much impervious to environmental threats. It’s also tough enough to survive drops of up to 10 ft (3 m). Originally designed to explore the surface of Mercury, Groundbot has been modified for terrestrial chores such as large-area patrol, explosive gas monitoring, and remote inspection. It can be fitted with up to four cameras (up to 360° field of vision), various sensors, night-vision systems, microphones, and speakers. Probably the most interesting feature is the drive mechanism, which basically relies on gravity. A controlled pendulum is held close to the ground when the bot is motionless. By lifting the pendulum, it can be made to roll in any direction. This produces speeds of up to 6 mph (10 kph) and the ability to handle inclines up to 20°. In case you’re interested in the details, Groundbot is 2 ft (0.6 m) in diameter, weighs 55 lb (25 kg), and normally runs six to eight hours on a charge. Its operating temperature range is -22° to 104°F (-30° to 40°C). Bot Can Toot Your Flute Proving that no idea is too silly to endure if it draws government fund- ing, the Anthromorphic Flutist Robot, created by Atsuo Takanishi at Japan’s Waseda University (www.waseda.jp), is now in its fourth incarnation and 18th year of existence. Model WF-4RIV (Waseda Flutist no. 4 Refined IV), features 41 degrees of freedom that have “enhanced its performance with more natural notes and smoother transitions between notes.” Specifically, the lips and tonguing mechanisms have been redesigned to be more like the corresponding human organs. Oh, sure, there are the usual academic rationalizations: “Clarifying the human motor control while playing the flute from an engineering point of view . Enabling the communica- tion with humans at the emotional level of perception . Proposing novel applications of humanoid robots .” and so on. But imagine spending 18 years of your life on this thing. For a demonstration, see www.youtube. com/watch?v=lYDW2A5-Cbw. Reportedly, work has begun on a saxophone-playing version, so maybe by 2026 Takanishi will come up with something as amazing as, for example, the Welte Orchestrion. First demonstrated in 1862, it weighs in at 1,500 lb, operates from music rolls, and drives 50+ pipes, bass, and snare drums, and a triangle. To hear one, visit www.asapackermansion.com/ orchestrion.html. Saved by the Bear At the other end of the utility spectrum is the Battlefield Extraction- Assist Robot (BEAR), developed by Vecna Technologies (www.vecna.com), a self-funded company created in 1998 and operated by alumni from MIT, Harvard, Stanford, Yale, Princeton, Berkeley, CMU, and other assorted institutions. Still in the prototype stage, BEAR is envisioned as a marriage of three elements: a powerful hydraulic upper body, an agile mobility platform with independent sets of tracked “legs,” and The Waseda Flutist No. 4 vs. the Welte Orchestrion. by Jeff Eckert Robytes The Groundbot mobile robot, revamped for security duties. Photo courtesy of Rotundus. Robytes.qxd 9/2/2008 3:37 PM Page 8 “dynamic balancing behavior” (DBB). DBB is how the robot hopes to balance itself on the balls of its “ankles.” In fact, the production model should be able to remain upright whether bal- ancing on its ankles, knees, or hips. It has already demonstrated the ability to pick up a realistically weighted human dummy and carry it around for 50 minutes without a break. According to Vecna, the purpose of the bear head is to comfort soldiers who might be put off by the otherwise “grotesque” appearance of the machine. New Robotics Conference If you’re working on robotics at the design level, you may be interested in the upcoming IEEE International Conference on Technologies for Practical Robot Applications (TePRA). It’s a new conference “aimed at catalyzing the development of enabling technologies and encouraging their adoption by robot designers.” It’s intended to be a cross between a dry academic conference and an industrial trade show, so you get an emphasis on practical applications coupled with technical presentations aimed at future applications. The stated goals are “to expose robot designers to new enabling tools, techniques, and technologies” and “to expose tool, technique, and technology developers to the needs of robot designers.” The event is scheduled for November 10th and 11th at the Holiday Inn Select Hotel, Woburn, MA. For details, visit www.ieee robot-tepra.org. Dragonfly V. 3 In July, the Delft University of Technology (www.tudelft.nl) intro- duced the third version of its artificial dragonfly, the DelFly Micro micro air vehicle (MAV). Weighing only 3 g and with a wingspan of only 10 cm, it flies by flapping its wings like an insect. The remote-controlled device is intended to be used someday for observation flights in dangerous or difficult to reach areas, and it already can be equipped with a tiny 0.5 g camera that transmits TV-quality images to a ground station. Given that it can fly continuously for only about 3 min (at 5 m/s), it obviously isn’t ready for commercial production. But Micro is just a stepping stone to the planned DelFly Nano (5 cm, 1 g), which will be able to move independ- ently using image recognition software, hover like a hummingbird, and even fly backwards. SV Robytes SERVO 10.2008 9 Vecna’s BEAR robot as employed on the battlefield. Photo courtesy of US Army. The DelFly Micro MAV. Photo courtesy of Delft U. Heavy Metal R o bot Kit Announcing the Gears Designed for Students and Professionals L Heavy Metal is engineered for rigors of daily use in classrooms, summer camps, workshops, labs . . . even combat robots! L Assembles quickly using fasteners of same size/pitch and threaded inserts. 10" wheel base, heavy gauge aluminum, 4-wheel drive, 3" rubber wheels, 3/8" axles, flanged bronze bearings, #25 pitch steel chain and sprockets. All drive components are keyed and broached. L Competition all-metal gearhead motors, gearbox rated at 500 oz-in of continuous torque. Heavy Metal accepts off-the-shelf engineering parts, plus components and control systems from GEARS IDS, FIRST* and VEX Robotics* kits. Contact Mark Newby mnewby@gearseds.com sWWWGEARSEDSCOM Lb for Lb the World's Toughest Robot Chassis Supports 200 lbs of standing weight! Heavy Metal 1 Kit includes chassis, motors, drive system, and wheels for $499.00. *VEX Robotics is a mark of Innovation First, Inc. and FIRST refers to © US FIRST (Foundation for the Inspiration and Recognition of Science and Technology) Robytes.qxd 9/3/2008 1:06 PM Page 9 10 SERVO 10.2008 You’re No. 1 . Really! Ian Ingram, BigBot curator and creator of the “You’re No. 1” robotic foam hand and finger interpretation atop the Andy Warhol Museum spoke about the BigBots, beginning with his own work (at my request). The nearly seven yards of Pittsburgh black and yellow foam hand and index finger spread the love by reaching out to visitors to say they were no. 1. The hand moved, posi- tioned itself, and pointed at various visitor outposts miles away and throughout the city using dual-axis hydraulics. One axis was a hydraulic motor and one was a hydraulic actuator. The hydraulics gave the hand two degrees of freedom (DOF) of movement. The first DOF held the hand straight up and twisted it around while the second moved it downward to point it at the outposts or to wave at people. All the action was automated by a small microcon- troller, though the original plan was to have kiosks at the outposts with remote triggers to activate the hand and point it in the specific direction of the kiosk that triggered the response. The robotic hand made use of sensing and a limiting switch — a gross encoder — which told the robot when to stop and start its movements. The hand was fitted with a camera that lined up in varying positions equal to a straight line to the different outposts. The PIC microcontroller was brought to life using software created in C programming. The software looks for limit switch hits, making plans for movement between where the hand is and where it needs to go to perform the pointing and waving, according to Ingram. The robot uses a motor to pump fluid to create pressure to activate and manipulate the hydraulics. The hydraulic valves use solenoids and are pushed by external signals from the microcontroller. The structure of the hand is steel weldments with polyurethane foam similar to the hands that people take to sports games. Semi-autonomous Percussive Devices Communicate Like Crickets The Crickets installation uses a number of interconnected robotic sculptures to imitate the action and reaction of group communication among packs of animals such as dogs or insects. The robots are equipped with wooden knockers controlled by solenoids to tap out their noises. Contact the author at geercom@alltel.net by David Geer Robot250 Features BigBots Robotic Artwork that Interacts and Responds Robot250 is a city-wide extravaganza of large scale interactive robot art projects, workshops, festivities, events, and film held July 11-27 in Pittsburgh, PA. Sponsored by Carnegie Mellon University, the University of Pittsburgh, and a number of local community groups like the Heinz Endowments, the program features BigBots interactive robot displays with artistic themes. Photos and caption information are courtesy of Carnegie Mellon University. The “You’re No. 1” BigBots robotic installation by Ian Ingram is a 20-foot tall robotic black and yellow foam hand and finger like the ones worn by fans of Pittsburgh’s most famous sports team. The maneuvering hydraulic hand appeared on the roof of the Andy Warhol Museum in Pittsburgh as part of the Robot250 Festival, which ran July 11-27, 2008. Ingram, BigBot curator, senior research associate, and artist-in-residence at Carnegie Mellon University, built the big hand, which pointed at passers-by around the city. Geerhead.qxd 9/3/2008 9:31 AM Page 10 . publisher@servomagazine.com ASSOCIATE PUBLISHER/ VP OF SALES/MARKETING Robin Lemieux display@servomagazine.com EDITOR Bryan Bergeron techedit -servo@ yahoo.com. Kerley subscribe@servomagazine.com MARKETING COORDINATOR WEBSTORE Brian Kirkpatrick sales@servomagazine.com WEB CONTENT Michael Kaudze website@servomagazine.com