Minutes of the PARTS meeting on March 2nd, 2002
Pete Skeggs opened the meeting by reminding members about our upcoming robotics competition, PDXBOT.02 to be held May 19th, 2002 in the Smith Center Ballroom on the Portland State University campus.
Pete showed the submissions for the competition logo; two grayscale designs by Tim Weaver, and three color designs by Shea Ivey. With a show of hands, Sheas designs were selected in a 24-to-3 vote. Pete said that hed like to see more submissions for a club logo, and encouraged members to send their designs to Warren Leach, firstname.lastname@example.org.
- Larry Geib showed his prototype line-following course , made of 1/4-inch thick white melamine-surfaced particleboard with black 1/4-inch wide stripes. Larry built a dovetailing jig to rout interlocking ends on the course pieces. This will allow courses of varying design to be laid out using a standard set of pieces. Larry reported that the event committee has discussed combining match racing with line following to increase the excitement of the event. The beginner course would be pretty simple; it would not have right-angle corners, or lines that cross themselves. The advanced course might include obstacles (gates that pivot up and down, ramps, teeter-totters, bridges, etc) and lines that cross, make right-angle corners, have discontinuities or variable line widths. Because of the obstacles, the advanced class will probably have size and weight restrictions to ensure that the robots can successfully navigate the course. Line following rules will be posted on the club web site as soon as they are finalized.
- Pete announced that Tim Weaver is in charge of obtaining displays of robotics and electronics technology, and encouraged members to contact Tim with suggestions or to loan demonstration equipment.
- Dana Weesner reported that the State of Oregon has assigned the club an identification number as a non-profit corporation. We still need to get IRS approval of our clubs application for 501(c)3 non-profit organization status. Funds to pay for this application were collected at last months meeting. Dana brought a jar into which members or visitors could place a free-will offering. Jonathan Fant suggested that we add a surcharge of $5.00 or $10.00 to the cost of the Mark III mini-sumo robot kit to fund club activities. Eric Stewart suggested an educational or student waiver of the surcharge. Pete explained that the PARTS executive committee, the Mark III design committee and the PDXBOT.02 competition committee have already discussed the kit surcharge, but that no final decisions have been made.
- Daryl Sandberg showed his prototype rover vehicle. He has added 4-wheel steering, and demonstrated the units 30-inch turning radius. His steering unit uses a power seat adjuster motor and quick-disconnect tie rod ends from McMaster-Carr. His next changes will include some sort of proportional steering control and beefing up of the suspension. (Daryl reported that he took his rover to work, and the guys there were pretty rough with it.) Daryl showed the Devantech digital magnetic compass (from Acroname) he added to his holonomic robot. He also showed Dave, a prototype drone robotic target for Goliath to chase. Dave has two servos with the drive electronics removed, the cases cut and mounted back-to-back to minimize width, and no intelligence yet.
- Kelvin Weesner showed a collapsible toy car he bought at a garage sale. He said it had good steering and nice wheels, and he wanted to turn it into a robot. He has also learned how to hack game cartridges.
- Tim Weaver has emailed a survey about interesting technologies for demonstrations at PDXBOT.02 and is awaiting responses from PARTS members who have potential displays. He also announced that he had surplus Okidata printers and other goodies to give away following the meeting.
- Dana Weesner showed a plastic bag full of stepper motors and offered to give one to anyone who is interested. He showed his BotBoard II and said it is huge when compared to the controller for the new Mark III robot. He also showed a nice aluminum mold for molding treads around his machined aluminum wheels.
- Tim Brandon showed small paper encoder discs that he had produced on a PostScript printer. He said that he would post his printer file on the club web site.
- Karl Kuchs reported that his robotic colony was done, and that he was getting a circuit board made for the NW Science Expo on March 21st at PSU. There is a chance hell get to go to MIT with his robotic colony. He will begin work with the Newberg High School team this afternoon to help complete the teams robotic chess player.
- Steve Hampson described an electric arc welder that he is selling to make room for a larger unit. His welder is multi-mode, capable of MIG / stick / TIG welding with either .030 or .035 wire. He does not have the TIG head. The welder operates off of 220 volt, single-phase power, but at 300 pounds is not suitable for apartment-dwellers. The price is $650.
- John reported that he had made a quadrature encoder for a small motor using a design posted on the Seattle Robotics club website.
- Paul Burkey reported that he had taken part in National Engineering Week in February, and had taken a robot to a 5th grade class.
- An unidentified visitor (sorry, no name tag!) was looking for miniature ribbon connectors for a Sharp camera board, and needed help replacing an unidentified surface mount part that was accidentally removed from an R/C receiver board when external wires were attached.
- Jonathan Fant showed his latest version of FRED. This version is constructed of Lexan plastic and has a rotating top platform, a Polaroid ultrasonic transducer, new stepper motors, timing belt drive, and large 4 wheels. He estimates that his chassis cost is about $100 without motors (or $300 with drive and platform positioning motors). He said that he has been using Gorilla Glue to make his Lexan joints; Mark Maxwell suggested the use of Devcon Plastic Welder. He showed a stepper motor driver kit ($20 from Amazon Electronics) that attaches to a PC parallel port, a low-profile model airplane aileron servo motor, a larger servo motor, digital compass, and a MotorMind driver designed for use with the Parallax BASIC Stamp.
- Eric Stewart reported that he had found usable lead-acid batteries at the local recycling center, and brought some Gates gel cell batteries to sell or trade. He brought his latest Marlin P Jones Associates catalog and a circuit board from a Microsoft optical mouse.
- Matt Ivey said that press releases about PDXBOT.02 would be sent out this month. Members can contact Matt (503-289-4112) for more information.
- Tim Rohaly said that he should be able to take orders for the Mark III mini-sumo robots beginning Tuesday (March 5th), and he plans to start shipping kits around March 15th. He showed the new plastic injection-molded wheels (complete with broccoli bands for traction) the mount directly to servo splines. The PARTS members who are developing sample software will get the first deliveries for development and testing. Tim had some excess Sharp GP2D12 sensors for sale at $8.00 each. Tim said that hed like to be able to deliver example programs for mini-sumo, line following, and sensor calibration; competitors could modify those programs to implement specific strategies. Jonathan Fant agreed to research the re-distribution of data sheets and software on CDs.
- Dan Gates said the injection-molded wheels fit the splined shaft of Futaba (and many other, but not all) brands of servo motors. The wheels can be purchased from the Southern Oregon Robotics Club for $5.00 a pair. Dan is getting chassis parts for the Mark III robot cut and powder coated. He showed a Dinsmore digital compass ($14 from Wirz Electronics) that is based on Hall-effect sensors and provides eight directions of heading information. He said that he is going back to school, and has started the Rogue Community College Robotics Club. He said we could expect about 10 entrants from RCCRC at PDXBOT.02.
- Brad Lewis reported that he had bought a micro web server to display an image from a robot-mounted X-10 camera. And, he had found an embedded Ethernet controller that will enable him to connect to his telebot up to 26 miles away. Brad needs to make a parabolic antenna, but hasnt had time. He also showed sample pieces of laser-cut plastic that his friend in Molalla cut with his 100-watt laser. A 1-cm cube had 100 holes drilled in it; the holes are large enough for a human hair to pass through. Brad is looking for parts-cutting jobs for his friend.
- Mark Medonis had some books to give away at the meeting. Mark showed his copy of USB Complete, Jan Axelsons latest interface standards book, as well as a Motorola USB development board he had recently picked up.
- Steve Davee brought his micro-sumo robots. One is autonomous, and the other is remotely controlled using the radio system removed from one of his Tyco Racin Ratz cars. He showed how he is getting easily-worked thin sheet metal from used Polaroid film packs. Pieces can be cut with scissors and easily belt to shape. He said that in his micro-sumo robots where weight is critical he has been using glue dots to hold components in place. He wants a better fastening method because the dots dont have much strength.
- Eitan Tsur showed a prototype hovercraft that he and his dad, Ron, had built. The body was a rectangular Styrofoam shipping insert like those used for metal computer cases. They had made a skirt out of a plastic bag that was inflated by the main fan.
- Pete Skeggs showed his Pico ball-bearing GWS sub-micro servo ($24 from Balsa Products). He said the output spur gear needs to be cut to permit continuous rotation, but two of these units back-to-back would fit within the 5 cm micro-sumo size limit. Pete has also put a new microcontroller in his Stellaluna mini-sumo robot .
The next PARTS meeting will be April 6th, 2002.