Tạp chí Servo
Vol. 5 No. 9 SERVO MAGAZINE VEX AUTOMOTIVE • BASHBALL • CAN NETWORKING • ROBOCUP • M-BOT September 2007 Cover.qxd 8/8/2007 9:33 PM Page 84 Order 24 hours a day, 7 days a week www.Jameco.com Or call 800-831-4242 anytime ©Jameco Electronics. *According to their web sites on July 23, 2007. Trademarks are the property of their respective owners. OTHER JAMECO ADVANTAGES: ■ More major passive, interconnect and electro- mechanical brands than other distributors. ■ 99% of catalog products ship the same day. ■ Lowest prices guaranteed, or we pay 10%. ■ Major brand names and generic equivalents for even greater cost savings. 5 10 15 20 25 We’re semi nuts We’ve got semis on the brain. Jameco offers more major brands of semiconductors than anyone — almost twice as many as these catalog distributors.* It’s another Jameco advantage. 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Intersil Integrated Devices Intel Corporation Fairchild Semiconductor Lattice Semiconductor Intel Corporation Intersil Freescale Semiconductor Lite-On Semiconductor Intersil Lattice Semiconductor Infineon Technologies NEC Corporation Lattice Semiconductor Maxim Integrated Devices Sharp Microelectronics Maxim National Semiconductor Intel Corporation ST Microelectronics National Semiconductor NXP (formerly Philips) Intersil Texas Instruments ST Microelectronics ST Microelectronics Lattice Semiconductor Texas Instruments Texas Instruments Linear Technology Lite-On Semiconductor Maxim Micron Technology Microsemi National Semiconductor NEC Corporation NXP (formerly Philips) Renesas Technology Sharp Microelectronics ST Microelectronics Texas Instruments Toshiba Free shipping on these and 79 other brands. Call for details. CoverInside.qxd 8/8/2007 7:50 PM Page 2 ;^ghi"XaVhhXjhidbZghZgk^XZ### ¹Ndj ]VkZ egdk^YZY eda^iZ! YZiV^aZY hjeedgi l]Zc > ]VkZ cZZYZY^i!]VkZWZZcbdgZi]VcVXXdbbdYVi^c\l]Zc^iXdbZh idejgX]Vh^c\Vhh^hiVcXZVhlZaaVhegdk^Y^c\bZl^i]a^\]ic^c\ [VhiZbV^agZhedchZh!egdbeiYZa^kZgnVcY]VkZbZiVcY\gZVian ZmXZZYZYbnZmeZXiVi^dc[gdbVgZiV^aZg^cZkZgngZ\VgYº GdWZgi<dgYdcJc^kZgh^in!6WZgYZZc DG9:GDCA>C:/ LLL#68I>K:"GD7DIH#8DBI:A/ ))%&,+&'(.'+, GdWdcdkV"& =D@JNDE7H"%(?C >c[gVgZYgVc\ZÃcYZg[dg ^cYddgZck^gdcbZcih 6JI=DG>H:9=D@JND9:6A:G =D@JNDJG<"%)AMhiViZd[ i]ZVgiaVhZggVc\ZÃcYZg HZchdgBdjci^c\=VgYlVgZ GdWdiX]Vhh^h!eVgih VXXZhhdg^Zh :VhnHiZe(%%%!VYkVcXZY hiZeeZgbdidgYg^kZVcY XdcigdahnhiZb B^XgdbdjhZX]Vhh^h :cignaZkZaXdcigdaaZg hj^iZYidhbVaagdWdi^Xh VcYXdcigdaVeea^XVi^dch Full Page.qxd 8/8/2007 7:54 PM Page 3 4 SERVO 09.2007 35 BASHBALL! by Steve Judd BotBash returns with a new game, a radically updated “Active Arena,” and a different approach to extreme robotic sports. 38 RoboCup 2007 by Dennis Hong, Karl Muecke, Robert Mayo, Jesse Hurdus, and Brad Pullins DARwIn’s first soccer tournament. 44 Build an Inexpensive Solar Trickle Charger From Junk by Alan Federman Harness the rays from the sun to power your outdoor bots. 46 Beginner’s Guide to Programming by Michael Simpson Lesson 3: Branch, LookUp, LookDown, and LCD commands. 51 M-BOT by Ron Hackett Part 1: Begin construction on this intelligent, autonomous robot controlled only by an eight-pin processor. 55 CAN Networking Southern Style by Fred Eady Put some CAN application code together and control an LED before adding additional motor driver hardware. 62 RoboGames 2007 by Peter Smith Recap of this year’s event. Features & Projects 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 ADDITIONAL 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 PAGE 62 TOC Sep07.qxd 8/8/2007 3:47 PM Page 4 09.2007 VOL. 5 NO. 9 SERVO 09.2007 5 ENTER WITH CAUTION! 26 The Combat Zone Columns 08 Robytes by Jeff Eckert Stimulating Robot Tidbits 10 GeerHead by David Geer AUVSI UV Sampling 14 Different Bits by Heather Dewey-Hagborg Neural Networks for the PIC Microcontroller Part 2 — Backpropagation 20 Ask Mr. Roboto by Pete Miles Your Problems Solved Here 67 Twin Tweaks by Bryce and Evan Woolley Robot vs. Wild 72 Robotics Resources by Gordon McComb Juicing Up Your ’Bot With the Best Rechargeable Batteries 79 Appetizer by Dan Danknick Time to Innovate 80 Then and Now by Tom Carroll People of Robotics Departments 06 Mind/Iron 07 Bio-Feedback 22 New Products 24 Events Calendar 34 Robotics Showcase 50 Robo-Links 76 SERVO Store 82 Advertiser’s Index PAGE 38 PAGE 51 TOC Sep07.qxd 8/8/2007 3:47 PM Page 5 Published Monthly By T & L Publications, Inc. 430 Princeland Court Corona, CA 92879-1300 (951) 371-8497 FAX (951) 371-3052 Product Order Line 1-800-783-4624 www.servomagazine.com Subscriptions Inside US 1-877-525-2539 Outside US 1-818-487-4545 P.O. Box 15277 North 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 CONTRIBUTING EDITORS Jeff Eckert Tom Carroll Gordon McComb David Geer Pete Miles R. Steven Rainwater Michael Simpson Kevin Berry Fred Eady Dennis Hong Karl Muecke Robert Mayo Jesse Hurdus Brad Pullins Steve Judd Peter Smith Alan Federman Ron Hackett Dan Danknick Chris Olin Ray Billings Jay Johnson Bryce Woolley Evan Woolley Heather Dewey-Hagborg CIRCULATION DIRECTOR Tracy Kerley subscribe@servomagazine.com MARKETING COORDINATOR Brian Kirkpatrick WEB CONTENT/STORE Michael Kaudze sales@servomagazine.com PRODUCTION/GRAPHICS Shannon Lemieux Michele Durant ADMINISTRATIVE ASSISTANT Debbie Stauffacher Copyright 2007 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. Academic vs. Commercial Robotics I had the fortune of participating in the 7th IEEE International Symposium on Computational Intelligence in Robotics and Automation (CIRA) conference, held this summer in Jacksonville, FL. Academic researchers from Asia, Africa, Europe, and the Americas presented their work on topics ranging from robot manipulators and cooperative robotics, to robot vision. As expected, the event was a concentrated refresher on the leading edge of robotics research. An unexpected take-away from my conversations with the researchers at the conference was the differences between academic and commercial robotics, and the merit of each perspective. The most obvious differences are a result of the reward systems applied to each group. Academic roboticists are rewarded for tackling intellectually challenging problems that can result in academic publications, with little or no regard for short-term commercial significance. As a result, academic roboticists tend to focused on niche areas that they can explore and perhaps claim for their own — whether it’s a novel algorithm, manipulator design, or robot configuration. Intellectual property, which provides leverage for academic promotion and securing government- and industry-sponsored grants, is guarded until publication. I liken the academic model to an inverted funnel, in which researchers drill down on an intellectually stimulating and novel domain, and only later broaden their approach to consider the broader applications of their work, including commercialization. Commercial roboticists, in contrast, are entrepreneurs. They are rewarded by the marketplace for recognizing and understanding a problem and then identifying a commercially viable technical solution. Their approach can be modeled as a funnel in that broad issues are considered first, and then choices are narrowed by issues such as intellectual property protection, cost of manufacture, competition, availability of distribution channels, support requirements, liability, and likelihood of follow-on products that will insure growth of a company. Commercial roboticists tend to focus on problem areas that are dull, dangerous, and dirty and know that superior technology is necessary but insufficient for commercial success. Intellectual property is either kept as trade secrets or protected with patents, trademarks, and copyrights. Despite these and other differences, academic and commercial robotics are intertwined in a symbiotic relationship. The best marketing strategy and business model will eventually fail if the underlying technology doesn’t adequately solve the buyer’s problems. Conversely, academic researchers increasingly rely on funding from private firms and corporations to supplement their typically limited academic funding. Academic departments are also aware of the pressure to develop robotic applications that eventually see the light of day, as opposed to a short-lived appearance on the Web or as a reference in an academic journal. Academic programs in robotics are judged in part on the placement success of their graduates in industry, which adds pressure on programs to produce graduates with knowledge and skills applicable to commercial products. The take-away for you is that, as an independent robotics innovator, you can Mind / Iron by Bryan Bergeron, Editor Mind/Iron Continued 6 SERVO 09.2007 Mind-FeedSep07.qxd 8/8/2007 6:52 PM Page 6 Dear SERVO: I read Pete Miles’ reply in the July SERVO about the problems of using infrared beacons in the house and wanting to offer another approach. I use RobotBASIC to develop a complete house navigation simulation using “infrared beacons.” It works perfectly, mainly because I used a very different approach. (Note: If you are not familiar with RobotBASIC, please see my article in the June issue). The assumption in the simulation was that I had 10 or so beacons (each with a unique ID code) that could be turned on by remote control (BlueTooth, for example). The program used a computer science data structure called a graph that essentially provided a “map” of the house. When the robot was requested from any given room, the program checked the map and turned on the beacons one at a time, in the proper order, allowing the robot to move (using the shortest path) from where it was to where it wanted to go. The simulation involved a complex floor plan and demonstrated how simple navigation can be if only some manufacturer would provide a beacon detector, and several beacons (that perhaps look like smoke detectors) each with their own ID code that could be set with DIP switches. Since beacons could be placed throughout the house (probably primarily over doorways) they do not need to be extremely powerful . typically, they would only need to be detectable from 15-20 feet. In the rare cases where that was not enough, two beacons could be used to get through a room or a hallway. The point is, I believe infrared beacons can provide an extremely easy-to-use, economical way for hobbyists to navagate a complex environment. My simulation would even go around objects found to be blocking the path and then resume movement toward the beacon. Of course, most microcontroller-based robots would not have the memory or math ability to deal with the graph data but the new version of RobotBASIC (2.0) provides a built-in protocol that allows all the standard simulation commands to control a real robot over a wireless link. This means even small robots now have the ability to be controlled by a complete, powerful language giving new life to the goal of AI in small machines. Hmmm . looks like I rambled some, but I am very proud of the capablities of RobotBASIC and I think it opens many doors to more intelligent control that have been overlooked because of previous limitations imposed by the required use of simple microcontrollers. John Blankenship Dear SERVO: This correction refers to Tom Carroll’s article on robotic arms. The following statements are incorrect: “the advantage of using R/C servos is the positional feedback;” “potentiometric feedback, as in R/C servos allow the controlling computer to know where each joint is positioned.” There are no feedback mechanisms built into any standard servo today, with the exception of the AX-12+ and a few specialized servos used in Biped type-robots. Alex Dirks, CrustCrawler benefit from aspects of both commercial and academic approaches. Before beginning your next robotics project, consider how you’d approach design and development from a commercial and then academic perspective. Certainly, you want to learn something from everything you do, but if you’re looking at making your innovation applicable to a larger audience, then you have to consider the business issues in component selection, design, potential sales volume, and follow-on products. When considering component selection, it helps to imagine that you’re building, say, 5,000 robots. Suddenly, a few cents for a component or the cost of an added square centimeter of pc board or aluminum chassis makes a big difference in overall cost. Sensors and other components that are just good enough for your application may not be pushing the technology envelope, but customers won’t care if the robots work as advertised. Conversely, a new microprocessor might be more expensive to install initially, but incorporating it in your design will give you a chance to learn about the device, and may provide a growth path for add-ons. The bottom line is that, with a combined approach, your robotics innovations can be both technologically and financially sound . SV SERVO 09.2007 7 Mind-FeedSep07.qxd 8/8/2007 6:52 PM Page 7 8 SERVO 09.2007 Research Seeks Human-Like Movement Robots are not generally known for smooth movement and gentle touch, but Oussama Khatib, a computer science professor at Stanford (www.stanford.edu) and a participant in the Honda Humanoid Robot Project, is trying to fix that. Conducting a study of several college students and a visiting Chinese tai chi master, the professor noticed that humans instinctively move so as to minimize effort and discomfort (such as how students throw their beer cans and pizza boxes on the floor rather than getting up and walking over to the trash can). So, rather than generating a slew of complicated trajectory-computation algorithms, he is taking an approach based on simply minimizing the energy the robot uses for a particular task. Smooth movements should use less energy than jerky ones, so the concept sounds valid (as long as the robot doesn’t decide to just switch himself off). So far, “StanBot” is a prototype that exists only as a computer simulation. But in a year or so, Khatib hopes to incorporate his concepts into one of Honda’s ASIMO units. Eventually, with this type of programming, it should be able to iron clothes and pick up the trash for us. Machine Has Adaptable Gait Last year, RunBot — developed at the University of Göttingen (www. bccn-goettingen.de), the University of Glasgow (www.gla.ac.uk), and the University of Stirling (www.stir. ac.uk) — gained renown for becoming the world’s fastest two-legged robot (relative to its size). It moves along at 3.5 leg lengths per second, which translates into 0.8 m/s or roughly 1.8 mph. The trick is that it walks using just a few sensors and detects only when a foot touches the ground and when a leg swings forward, mimicking the way control reflexes work in humans. Originally, RunBot just trotted around in a circle, on a flat surface. (A couple amusing mpeg videos are accessible at www.cn.stir.ac.uk/ ~tgeng/research.html) Now the 30 cm device has been fitted with an infrared eye that detects a slope in its path and automatically adjusts it gait. Like a human, it leans forward slightly to adjust for an uphill grade and takes shorter steps. In its first attempt to climb a hill, it fell over backwards, but the control circuits managed to learn from the experience and did well after that. Upgraded UAV Deployed On a more menacing note, the US Air Force Air Combat Command (www.acc.af.mil) recently announced that a new UAV, the MQ-1 Reaper (as in grim), is ready for deployment in Afghanistan “soon.” Larger (3,700 lbs, 66 foot wingspan) and more powerful than the better known MQ-1 Predator, it can fly at 300 mph, reach altitudes of 50,000 feet, and carry payloads up to 3,750 lbs. The $69.1 million craft is designed to attack time-sensitive targets and hit them primarily with gravity bombs, but it can also be fitted with Hellfire mis- siles and some other things that could spoil your day. A secondary mission is to perform intelligence, surveillance, and reconnaissance duties, using sensors to send real-time data to com- manders and intelligence specialists. The MQ-9 isn’t truly robotic at this point, as it requires a crew of two Oussama Khatib and a mechanical pal. Photo courtesy of Stanford University. RunBot has been upgraded to deal with sloped paths. Photo courtesy of Bernstein Center for Computational Neuroscience. The MQ-9 Reaper UAV is ready for action. Photo courtesy of USAF Air Combat Command. by Jeff Eckert Robytes Robytes.qxd 8/7/2007 3:53 PM Page 8 (pilot and sensor operator). But at least they sit at a remotely located ground control station. Eurobot Passes Tests Under development since 2003 by the European Space Agency (ESA, www.esa.int), the multijointed (seven joints plus one end effector and camera per arm), three-armed Eurobot has undergone operational testing in the Neutral Buoyancy Facility of the European Astronaut Centre in Cologne. In the trials, the wet model — which is similar in size and configuration to the planned space flight model — was checked for its ability to move and manipulate objects, provide coordinated multi- arm movement, and recognize obscured targets. By all accounts, the tests went very well. According to Philippe Schoonejans, the Eurobot project manager, “Not only has it been demonstrated that Eurobot can walk around an orbital station autonomously and safely, using no more than the existing EVA handrails, it is also becoming clear that Eurobot can really help the astronauts. And in the next phase, we also plan to demonstrate its use on a planetary surface .” “Tuabot” Aids Breeding Research Meanwhile, down in laid-back New Zealand’s Stephens Island, a robotic lizard is helping to preserve the tuatara species by pretending to be an available bachelor. The creatures have been around for 200 million years, so it would seem that they have this breeding thing under control. Nevertheless, Victoria University (www.vuw.ac.nz) post- doctoral student Jennifer Moore (actually a Michigan native) wants to understand how males establish dominance and attract females. Enter “Robo-Ollie,” made from a cast of a recently departed real lizard known as Oliver. The rubber-skinned creature runs off a nickel-cadmium battery and tries to imitate the aggressive behavior typical of male tuataras. Ollie can’t actually walk around, but he can move his head. He didn’t do all that well in initial trials, as he just bobbed his head, which turned out to be a female signal. He was then reprogrammed to open his mouth and gape, which apparently irritates other males to no end. Among real tuatura, this degenerates into puffing (which Ollie hasn’t learned yet) and all-out warfare in which the reptiles often lose their tails. About 75 percent of the males turn out to be lonely losers, and the other 25 percent get to produce all of the young. As one might expect, the winners tend to be the largest individuals, some of which can be 90 years old. Moore suspects that smell could play a role in the mating process, so research continues. SV Robytes Eurobot is lowered into the Neutral Buoyancy Facility for operational concept testing. Photo courtesy of ESA. A robotic version of this tuatara will mimic the real thing to help researchers. Photo courtesy of Ohio University Research (www.research.ohiou.edu). SERVO 09.2007 9 Hobby Engineering Hobby Engineering Hobby Engineering Hobby Engineering The technology builder's source for kits, components, supplies, tools, books and education. Robot Kits For All Skill Levels Motors, Frame Components and Scratch Builder Supplies. ICs, Transistors, Project Kits BEAM Kits and Components Books and Educational K Most orders ship the day received! World-wide shipping. Convenient payment options. Order by Internet, phone, fax or mail. www.HobbyEngineering.com 1-866-ROBOT-50 1-866-762-6850 1-650-552-9925 1-650-259-9590 (fax) sales@HobbyEngineering.com 180 El Camino Real Millbrae, CA 94030 Visit our store near SFO! Robytes.qxd 8/7/2007 3:54 PM Page 9 10 SERVO 09.2007 The 2007 Unmanned Vehicle Show The Unmanned Systems North America arguably hosts the largest robot, drone, and UV hardware showcase and information exchange in one place at one time. This year’s extravaganza “transformed” the Washington Convention Center in DC, August 6th through the 9th. The event, growing year after year for 35 years, was the biggest thus far, according to an AUVSI media release. This year’s event — sponsored by Honeywell, Northrop Grumman, AAI Corp., the Air Force Research Lab at Tyndall AFB, EADS North America, the Israel Aerospace Industries LTD, NovAtel, and SpaceAge Control — hosted more than 200,000 square feet of research and military robot vehicles. The UVs conquered the Convention Center, making it their own for four days of presentations, speeches, techni- cal sessions, and up-close examinations. Airborne, water-treading, and land-roving robots shared the stage with representatives from the Army Special Ops, Naval Meteorology and Oceanography Command, The Defense Science and Technology Agency in Singapore, and other offices, commands, and branches. Details, Details An audience of some 4,000 inter- ested observers the world over flocked to Washington to get a gander at the latest trends in UVs. Visitors included members of academia, representatives of foreign governments, and industry leaders and decision makers, according to AUVSI. Attendees were filled to the brim with new technology briefings and operational reports and live UV exhibits. They were offered a glimpse into the future in the form of a live operation show at Webster Field near Patuxent River Naval Air Station in St. Inigoes, MD where UVs trampled the ground, took flight, and flaunted their larger-than-life capabilities. From Beyond the Shadows, it Sees! UVs making a showing at the 2007 AUVSI event (present in 2006, as well) included AAI Corporation’s Contact the author at geercom@alltel.net by David Geer AUVSI UV Sampling The Association for Unmanned Vehicle Systems International (AUVSI) — the largest non-profit globally that is dedicated to unmanned systems — hosted its annual Symposium in August 2007. AUVSI members trek the world making their way to this event, packing their UV wares and showing them for government organizations, industry, and academia. AUVSI Symposium 2006 show room with UVs on display. Geerhead.qxd 8/7/2007 3:56 PM Page 10 . publisher@servomagazine.com ASSOCIATE PUBLISHER/ VP OF SALES/MARKETING Robin Lemieux display@servomagazine.com EDITOR Bryan Bergeron techedit -servo@ yahoo.com. Mind/Iron Continued 6 SERVO 09.2007 Mind-FeedSep07.qxd 8/8/2007 6:52 PM Page 6 Dear SERVO: I read Pete Miles’ reply in the July SERVO about the problems