In the November/December 2011 issue of Robot Magazine, Terry Jackson and Salvador Garcia of the Chibots robot group authored an article titled “2011 Midwest SRS RoboMagellan Competition.” The subtitle was “There can be only one!”

This exclusive online bonus content is a supplement to the main story and consists of five sidebars detailing some of the robots that participated in the RoboMagellan competition.
–the editors

Robot name: Wheel-E
Builder: CIRC (Central Illinois Robotics Club)
Cost & hours to build: not given
Outstanding features:

  • Foxconn Mini-ITX motherboard with dual-core Intel Atom and 2 GB RAM
  • OCZ Technology 30 GB solid state drive
  • Atmel AVR based controller for sensor input and motor control
  • 12 V 10 AH Ni-MH battery
  • Differential drive allows zero turning radius
  • Parallax HB-25 electronic speed controllers (2)
  • Maxbotix ultrasonic rangefinders (4)
  • Suspension and tires from a Traxxas T-Maxx RC truck
  • Chassis designed using Solid Works 3D CAD design software
  • Custom machined polycarbonate parts fabricated using a Probotix PROBOTIX Comet CNC router
  • Custom aluminum andplastic parts fabricated using Sherline CNC lathe and milling machine
  • OceanServer OS5000-S compass and Locosys LS20031 GPS unit
  • Cone location using a Logitech C310 HD webcam on a Lynxmotion pan-and-tilt assembly
  • Programmed using Microsoft Visual Basic and C# 2008 Express and RoboRealm
  • Belkin Wi-Fi for sending telemetry to base station laptop
  • Spektrum RC transmitter and receiver for safety stop switch
  • Magnetic shielding materials from LessEMF.com

 

Description:
The Central Illinois Robotics Club (CIRC) is based in Peoria, Illinois. Their robot utilizes two control systems. The first is an Atom based Mini-ITX computer running Windows XP which is responsible for the high level functions. The second is an AVR-based controller that handles sensor inputs and motor controller commands. An onboard compass and GPS unit steer the robot to the area where the orange cone is located. Once there the vision system takes over to locate the cone. For wheels and suspension Wheel-E uses parts from a Traxxas RC truck. Its sophisticated differential/belt drive allows the robot to maneuver in many different kinds of terrain.
An interesting aspect of this robot was a peculiar set of metallic disks that were positioned over the motherboard. These had been specifically placed there to act as a shield to mitigate electromagnetic interference that was causing problems with the GPS.

Website: http://circ.mtco.com/
 

This magnetic shielding foil helped eliminate much of the electromagnetic interference that was preventing the GPS from getting a fix.A close up of the ultrasonic rangefindersThe Wheel-E Logitech C310 HD WebcamThe wheel suspension from a Traxxas truckA close up of the OceanServer OS5000-ScompassA close up of the GPS module, revealing the (left to right) OpenLog serial data logger that logs all GPS output strings to a 2GB micro-SD card, the Locosys LS20031 GPS module and the Sparkfun FT232RL USB to serial breakout board.

 

Robot name:Robo-RabbitBuilder:Tyler WulfCost & hours to build:$1,000/250 hoursOutstanding features:

  • Modified Traxxas Stamped RC truck with original steering servo, throttle motor and battery
  • 7.2V Ni-MH 3600 mAh battery for the electronics
  • Gumstix Verdex Pro xm4 Computer On Module (linux kernel 2.6.21) with an Intel PWX270 processor
  • Wifistix networking daughter card for Verdex Pro with FCC Wifi module
  • Gpsstix daughter card for Verdex Pro with breakout board and a ublox LEA-4H GPS module
  • Parallax ping ultrasonic rangefinders
  • Acroname Electronic Compass R117
  • Logitech pro 4000 webcam Â
  • Programming done in C

Description:
Tyler is working towards his Master’s degree in Electrical Engineering at South Dakota State University and Robo-Rabbit is his Research Design project. The robot uses both a GPS and a compass to steer to the general area of the orange cone. Once in the vicinity it uses the Web cam to locate the cone based on color. Ultrasonic rangefinders help the robot avoid obstacles. The robot’s control system is written in C.

 

Robo-Rabbit’s battery pack used to power the electronics. The GPS antenna sits on top of the battery.The compass module.A close up of the sonar modules and the Webcam used.

 

Robot name:No NameBuilder:Rick BrooksCost & hours to build:$1,000/1,000 hoursOutstanding features:

  • Parallax Propeller controller
  • Programmed in Spin
  • Traxxas E-Maxx 16.8V monster R/C truck chassis
  • Honeywell HMC6352 compass
  • u-Blox 5 based GS407 GPS unit
  • Titan 775 motor geared 15/72 with a 2 speed transmission
  • MaxBotix XL-EZ1 ultrasonic rangefinder (5)
  • RoboteQ AX1500 motor controller

Description:
No Name was originally built to be another entry (not a serious competitor) in the Chibots SRS RoboMagellan 2008 contest.  It also served as motivation to advance beyond Basic Stamp controlled sumo robots of the past and as an excuse to play with new sensors and other hobby robot technologies coming on the market.  No Name was to be a robot that would operate
outdoors and, perhaps drive around the house or on the sidewalk around the block.

The twin motors of the Traxxas E-Maxx chassis were replaced with the single Titan motor with its transmission locked in low gear.  Rear Steer was added to increase maneuverability.  Since the robot now weighs 13.75 pounds, heavy duty springs and shocks were adjusted to produce a very stable sensor platform at higher speeds over a typical RoboMagellan course.  Stability control is provided in the software so that the robot will not flip over or roll on its own.  The original motor control was replaced with the RoboteQ AX1500 for ease of use and reliability.

The main control board is very simple.  It has a Parallax Propeller Prop Stick USB for all of the processing power needed.  A four line LCD is included that displays six different user selectable screens to keep track of all of the sensor inputs and control outputs. A rolling code receiver acts as the remote kill switch.  A micro SD card holder records GPS position in KML file format.

There is an I2C IO expander (PCF8574AN) because as Rick puts it “I just because I wanted to play with one”.  Finally, five voltage regulators (two switched and three analog) provide the power for all of the electronics. The only protection on the Propeller pins is a group of serial resistors (2.2K for outputs and 10K for inputs).

A Lynxmotion encoder is located where the second E-Maxx motor would normally be mounted.  Its primary function is to provide speed input for stability control.  It also provides the total distance traveled on the RoboMagellan course.  Directional feedback is simply provided by the Honeywell compass.  The GPS unit furnishes very reliable location information for updating distance and direction to the next waypoint.  Finally, the five sonar units both avoid objects in the robots path and provide the exact location of the destination cones.

All software is from either the Parallax Propeller Forum or the Parallax Propeller object exchange.  No additional software needed to be developed, although the various Objects and Methods were modified to produce the exact characteristics desired for this application.  All of the basic functions of the robot operate on five of the Propeller cogs.  The sixth cog provides simplified user input of waypoint commands for the RoboMagellan course and other manual functions.  The seventh cog is needed to write GPS data to the uSD card.  Finally, the eighth cog is used for the R/C receiver when it is plugged in for testing.

Website: http://brooksbots.com/

 

The robot’s battery neatly tucked into he robot’s side.The HMC6352 compass module strategically placed as high above the ground as possible.The encased GPS module.The main controller board with the Parallax Propeller plus some support circuitry.A close up of some of the sonar modules.The wheel suspension from a Traxxas truck

 

Title:Team ConeheadRobot name:  SDRBuilder:Team ConeheadCost & hours to build:$700 (so far)/125 hoursOutstanding features:

  • PC – Giada Book PC , Newegg.com, # N82E16856176001
  • MCU – Devboard-M32, AVR-based microcontroller board, wrighthobbies.com
  • Motor Driver – Pololu Dual VNH2SP30 Motor Driver Carrier MD03A
  • Power – 14.8v 5AH LiPo packs, total of 300 watt/hours (4)
  • GPS – Pharos iGPS-500
  • Sonar – MaxSonar-EZ1 (2)
  • WiFi – Onboard WiFi Router for remote access
  • Programming, PC side done in Visual Studio C# and RoboRealm and Devboard-M32 programmed in Bascom

Description:
The team’s goal was to build a durable and weatherproof robot that could easily overcome the obstacles of an outdoor arena. We settled on a treaded tank design as our first full prototype. We opted to go large and leverage the full weight limit allowed.  The tank is 21-1/2” wide, 29” long and 15” tall and weighs 48 lbs. It features 3-1/4” wide tank treads made from slat top conveyor chain. Strips of rubber stair tread were glued to each link to provide excellent traction on any surface.  The tank’s electronics and sensors are completely enclosed to protect them from weather and to minimize the possibility of the tank being damaged by collisions with obstacles.

It can climb over 5” barriers and go through rough and rocky terrain. The prototype chassis is made of various materials – acetyl and styrene plastic, plywood and aluminum angle. The final chassis will be welded 6061 aluminum. The wide treads and weight allows the tank to navigate through the heavy grass, over uneven terrain and across the multitude of surfaces that are encountered on the competition course.

Team Conehead was formed in 2009 by Eddy Wright and John “KJohn” Kjellman.  Our first Robomagellan entry was a large scale toy tank with an onboard PC. Unfortunately, the toy tank was not durable and did not last to see a second contest.  In 2011, Team Conehead expanded to include Stuart Hecht and Glen Aidukas, both avid designers and robot builders.

Eddy Wright – long-time electronics enthusiast that began working with robots in the late 1990s. Eddy joined Chibots in 2001 and is still an active member. In 2002, Eddy formed Wright Hobbies LLC, a web-based electronics and robotics design, manufacture and sales company (http://www.wrighthobbies.net). Eddy lives in Bolingbrook, IL.

John Kjellman – (aka KJohn) Been creating robots since the late 1990s, first using Lego Mindstorms and later Vex, Tamiya and various kit parts. An active Chibots member since 2003.  A systems architect and software engineer by trade, also an instructor at Moraine Valley Community College teaching courses in operating systems and .NET development. John lives in Orland Park, IL.
Stuart Hecht – Was introduced to Chibots at their 2010 RoboMagellan and quickly decided to join them at their next meeting.  He enjoys designing mechanical systems and the pure logic of programming. Stuart lives in St. Charles, IL.

Glen Aidukas – IT Manager at a small software company with experience in hardware design. Glen has been involved in electronics since 1990 and robotics since 2003. In collaboration with Wright Hobbies, Glen developed the Bahbots controller, an advanced microcontroller board for robotics and electronics projects. Glen is a very active member of the robotics club in Philadelphia called Philly Robotics (phillyrobotics.org). Glen lives one hour outside of Philadelphia, PA.

 

The robot’s rear panel displayed various switches to control various components, a ventilator and the emergency stop button.The sonar modules were embedded inside the robot so that they would not come loose when the robot collided or went past obstacles.The robot used an HD webcam to locate the orange cones.The Giada book PC.TI PTN78060 High Efficiency DC to DC convertor (left) and switch connection/power distribution (right. Both circuits used the PB10 protoboards.Some of the internal components that made up the SDR robot.A shot featuring the tank treads.The inner working behind SDR’s front panel.

SDR images by Eddy Wright

 

Title:Blast From the Past: The First CompetitionThe first Midwest SRS RoboMagellan competition was held in 2008 at Moraine Valley Community College. Chibots organizers liked the campus due to its center quad, an area lush with vegetation, grass, uneven terrain, trees and cement sidewalks. This environment posed a number of challenges to the robot, including unseen “dangers” such as metal rebar or conduits under the sidewalk that affected the compass’ functionality.Team Hassenplug was a major part of this event. They brought 4 different competition entries, all made using LEGOs Mindstorms. Other competitors included Team Conehead, represented by Eddy Wright and John Kjellman, Eric Gregori and Rick Brooks. While the Team Hassenplug robots all ran, the Team Conehead and Eric’s robots had problems and were unable to run the course.The winner of our very first competition in 2008 was Steve Hassenplug, using a 100% Lego robot he called the Green Monster.  Steve is known to many in the robotics community for his leadership in creating Monster Chess, a Lego-based robotic chess game.  The game is played on a laptop and radio-controlled robotic chess pieces move about an eight-foot square playing area.  (See www.teamhassenplug.orgor type in monster chess in your favorite search engine)Aside from the 4 competitors, others brought their robots to show them to the eager crowd. Among the people showcasing their robots were Jeff Sampson and Kenneth. The weather was hot and humid as it usually is during this time of the year, although I don’t remember anyone bathed in sweat at the end of the competition as it happened this year (2011).
John Brost’s LEGO V2One of Jeff’s creations.A work in progress, by JeffKenneth’s marvel of engineering and construction.Rick Brooks’ No Name, 2008 version.Bryan Bonahoom’s LEGO robotEric Gregori’s entry. Notice the Netbook.Team Conhead’s tank entry.Group picture, left to right: John Brost, Bryan Bonahoom, Steve Hassenplug, Rick Brooks, Eddy Wright and John Kjellman (AKA KJohn, the man, the myth, the legend)
BP images by Jeff Sampson
BP2 images by Steve HassenplugGreen Monster
by Steve HassenplugGreen Monster competed in the first three Chibots RoboMagellen events, finishing the course all three times.  It is an all-LEGO robot that uses the LEGO MINDSTORMS NXT as its main controller and was programmed using RobotC.

The primary navigation source was an external GPS connected through the MINDSTORMS’ built-in bluetooth to receive the GPS coordinates from which it could calculate the direction and distance to each waypoint.  Waypoints were entered by simply walking through the course with the GPS and NXT.

Green Monster has two parts to the driving base.  The main section has two drive motors for differential-drive (tank-style) along with the NXT and most of the sensors.  The tail section has the mounting for the GPS, and a single drive motor connected via a single axle to both back wheels.

The robot’s main section contains a sensor array that includes a HiTechnic compass sensor for directional navigation, a single ultra-sonic sensor for object detection, a camera sensor that is programmed to identify an orange blob within it’s field of vision (for cone detection), and a touch sensor to detect when the robot actually contacts the cone.

To avoid getting stuck, the software will scan the ultra-sonic sensor for objects, watch the wheel encoders (built into the motors) to ensure the wheels are moving, and monitor the speed value returned from the GPS.  If any of these fail their test, the robot will stop, turn the front wheels, and back-up for a couple seconds.  Then, it will check the compass, and follow the new heading for several seconds (again scanning to ensure movement) before recalculating a new heading, based on the new GPS coordinates.

The Green Monster software will also generate a KML file which contains a log of GPS coordinates and robot-state information (what the robot was doing during the run) that can be used with Google maps to generate a complete record of the run.

 

Steve Hassenplug’s LEGO Green MonsterMap of the 2011 SRS RoboMagellan course at center quad of Moraine Valley Community College. Blue marker by Start label denotes starting position, orange markers denote approximate cone locations.

More information and video can be found on the web site: http://www.teamhassenplug.org/robots/GreenMonster

 

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