Critical Design Review of FIRST Robotics Team 190: Gompei and the HERD
This document presents the Critical Design Review for the WPI FIRST Robotics Team 190, conducted on February 17, 2006, led by advisor Ken Stafford and director Chris Werner. It details the design concepts for the 2006 game, including mechanical controls, gameplay strategies, and robot functionality. The review covers features such as six-wheel drive, ball collection, launching mechanisms, and autonomous strategies. Additionally, it outlines timelines, key milestones, and competition schedules for the season.
Critical Design Review of FIRST Robotics Team 190: Gompei and the HERD
E N D
Presentation Transcript
Critical Design Review WPI / Mass Academy FIRST Team 190: Gompei and the HERD Friday, February 17, 2006 Presented By: Ken Stafford, Team Advisor Chris Werner, Director of Operations
Outline 2006 Game Review Design Concept Review Mechanical Controls
The Game Game Animation
Design Concept Review • Established an ordered list for gameplay: • Score balls • Collect/Contain Balls • Score on platform • Defense-specific • Push Balls
Final Design • Six-wheel drive with two speeds • Ability to get balls from the floor and human player • Controlled delivery to shooter device • Ability to shoot balls into center goal on-the-fly from our side of the field • Many offensive and defensive autonomous options
Mechanical – Driveline/Chassis • Driven by 4 CIM Motors through a two stage reduction • Six 5” rubber caster wheels • Provide both traction and shortened wheel base • Speeds up to 9 ft/s • Ludicrous Speed Drive • Four 3” rubber caster wheels • Powered from main wheels • Pneumatically raised and lowered • Provide speeds up to 16 ft/s
Mechanical – Ball Collection • Two 2” PVC rollers in front of rigid back panel • Powered by mini-bike motor • 19” long to provide large contact area • Hole pattern to assist in gripping of balls • Spins at 3000/1500 rpm • Provides 20% “squish” of ball • Center deflector • Effectively creates two “ball paths” • Diverts balls upon entering robot
Mechanical – Ball Sorting/Storage • Five by four “revolver” • Allows for quick and easy ball sorting and access • Effectively stored in “single file” • Approximately 25 ball capacity • How it works • Balls filled into two front openings • Balls gravity-feed from opposite end • Pneumatic “flapper” allows for 72-degree indexed rotation to occur
Mechanical – Ball Launching • Ball pitcher on turret to allow for 360 degree shooting (1½ total turns) • Driven by globe motor to CNCed Lexan sprocket • Ability to score from 6 to 21 feet using same release angle • Fixed deflector angle allows wide shooting range due to ‘flat’ trajectory
Mechanical – Ball Launching • Balls given backspin to “roll up” deflector • Contain pitcher mechanism at bottom • Pneumatic cylinder to lift ball into pitcher • Two 4” rubber wheels in series • Driven by two Fisher Price motors • First wheel at 4000 RPM; second wheel at 7000 RPM • Provides 20% “squish” • Imparts exit velocity of ~10m/s
Controls • Controls challenges: • Continuously keep the turret/pitcher aimed at the center goal even while the robot is moving • Operate all the other robot mechanisms to ease the human operator workload • Multiple autonomous strategies including scoring on the center target during initial 10 sec period
Controls – Navigation • Distance Measurement • CMU Camera • Computes distance to target using color tracking and calculating based on y-axis • Computes horizontal offset using x-axis position • Gear Tooth Counters • Provide velocity information for shoot-while-driving • Robot Orientation • Solid-state gyro provides heading information
Controls – Additional Sensors • Optical sensors • Balls in “ready to fire” position • Full/empty slots in revolver • Wheel encoder • Monitor the speed of the pitching motors to allow for proportional integral adjustments • Roller-follower • Limit switch to indicate position/index of revolver • Flapper sensor • Detects when flapper is fully closed before revolving
Controls – Autonomous • Very similar to driver-operated periods • Vision camera tracks light and determines when to shoot • Ability to select delays and different paths to drive for unpredictability and compatibility with alliance partners
Controls – Operator Interface • Driver controls both driveline and ball collector • Operator station to control ball launching • Switch to indicate offensive/defensive periods • Ability to fine tune the shooting vector • Fully automated or fully manual shooting modes • Sensor feedback to operator • Indicator lights to show target acquisition
Timeline Milestones • Jan. 7th – Kickoff • Jan. 11th – Strategy decision • Jan. 15th – Overall configuration • Jan. 27th – Preliminary Design Review • Jan. 30th – Chassis built • Feb. 5th – Driver try-outs • Feb. 7th – Mechanical subsystems built • Feb. 11th – Systems integrated • Feb. 17th – Critical Design Review • Feb. 21nd – Ship robot
Competition Schedule • Granite State Regional (Manchester, NH) • March 2nd – 4th, 2006 • Florida Regional (Orlando, FL) • March 10th – 12th, 2006 • Championship Event (Atlanta, GA) • April 27th – 29th, 2006 • BattleCry@WPI 7 (Worcester, MA) • June 23th – 24th, 2005
Questions? For more information visit our website at http://www.wpi.edu/~first/ Everyone is welcome to stop by and visit us in the lab (Higgins 005) or at any competition (just ask for details!!)
