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Dewbot VI first thoughts. Hong Kong & in-transit 10-January-2010 Clem McKown. Essential Capabilities. Ability to climb 45°, 13” high “bumps” without capsizing – gotta get over the hump! – fast fast fast Need to get balls over the bumps or through the tunnels and into goals fast
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Dewbot VI first thoughts Hong Kong & in-transit 10-January-2010 Clem McKown
Essential Capabilities • Ability to climb 45°, 13” high “bumps” without capsizing – gotta get over the hump! – fast fast fast • Need to get balls over the bumps or through the tunnels and into goals fast • Need to herd balls – fast • That said, not sure the robot needs to be particularly high speed – it needs to do its business without a lot of hesitation
Scoring • Scored Ball – 1 pt • Elevated Robot – 2 pts • Suspended Robot – 3 pts • Less penalties
Balls • 3 start far; 2 mid; 1 near • 8.75” typ diameter - ~1 lb • All reentered balls reenter mid – but are likely to role to far through tunnel • Scoring tends to send balls to opposing alliance side of field
More Balls • Balls cannot extend more than 3” inside the frame perimeter • Balls cannot be carried (must remain in contact with floor) • Only one ball at a time may be possessed • Possession means that if the robot spins in place or backs up, the ball stays with the robot • But several may be herded
Elevated – 2 pts/robot • Completely above the plane of the platform and in contact with the tower • Platform is 20” off the floor • Is a robot on the platform “Elevated”?
Suspended – 3 pts/robot • A robot only in contact with an elevated robot or a suspended robot
Penalties - -1 pt each • Handling balls before they are in the Corral • Not using Trident to return balls (2x) • Ball return timing • Lots more!!
Crossing the line • Completely crossing the centerline in autonomous will result in a penalty
In the zone • Only one alliance robot may be in the opposing alliance’s zone
Configuration (Envelope) • 120 lb • Excludes battery & bumpers • Normal – at the match start and during normal play, the robot must stay within this envelope • 28” x 38” • 60” tall • Finale • 84” diameter cylinder • 90” tall
Bumpers • Bumper zone is 10-16” off the floor • Bumpers must protect the entire frame perimeter • Must protect corners • Must be backed by frame • 6” minimum segment length • Must be solid red or solid blue color – bumper color will indicate alliance • May be marked with Team # only • 20 lb max (not included in robot wt)
Extensions beyond frame perimeter • Solely to interact with the ball, objects below the bumper zone (10”) may extend out to the bumper perimeter for no more than 2 sec • Cannot extend again for 2 sec thereafter • Robot can extend to Finale Configuration to right itself or alliance partner • Robot can extend to Finale Configuration during last 20s to Elevate or Suspend
Autonomous • 15 s • Goal • If in mid or far field – herd/shoot balls into next nearer field • If in near field – score 1 ball
Tunnel • 36” wide x 18” tall • A short robot could pass through • During normal play, there is no need for extensions above 18”
The Hump • Probably only able to cross hump driving in long (x) axis (unless CG very low) • 6wd will tilt 45° on climb and decline – with a significant tipping moment on the decline • 4wd will tilt less and reduce tipping moment – as long as it does not bottom out • Keep CG low and centered! • Power & traction needed
Pneumatics • Max of 4 Clippard tanks allowed • Solenoid valves may have a maximum 1/8” NPTF port size and 0.32 Cv • Cylinders • Any number • 24” maximum stroke • 2” maximum diameter • Any configuration • 60 psig max working pressure
Motors • Allowable motors are • All KoP Motors • Unlimited number of servos with 55 oz-in torque & 100 rpm rotational speed • Unlimited number of FTC servos • A maximum of 3 additional (5 total) CIM motors • There are (4) Nisso-Denko motors (2 each L & R) in KoP – these have worm gear reduction – (4) couplers provided • 2 Fisher Price -9015 motors (& plastic gearboxes) • 1 Mabuchi motor RS555SH-2670 • 1 Mabuchi motor RS555VC-3754 • No Globe motors
Budget Limits • $3,500 Robot limit • KoP parts valued at $0 • $400 max per component • Individual fasteners <$1 ea are excluded from this calculation • “Recycled” parts valued at undepreciated original value
Herder • Under-bumper herder/pusher/shooter should be feasible • Probably pneumatic push/shoot • Prevent ball penetration under frame >3” • Use 3” sides to prevent ball loss • Push balls over hump (with partial climb) or shoot through tunnel or into goal • 2 sec max extension • Best if full frame width… • Better if wide orientation • Herd more balls • Herd balls easier • Corresponds to tunnel & goal width
Ideas • Keep robot low in normal configuration • Low CG – tip-proof (like DEWBOT V) • Fit through tunnel? • 4wd to moderate tipping angles and moment • Pivot or wide 4wd to enable wide herding & shooting (need to manage tipping potential) • If Pivot, Snake & Automobile modes seem more useful than Crab
Ideas • Tilt-a-frame to climb onto Platform Driven wheels Undriven tilt lift
Ideas • Shooter / pusher / herder device • Same shooter / pusher / herder idea on 2 axis w/ pivot drive • For short side (x-drive), could be almost 28” wide if front wheels are shifted aft • For long side (y-drive), would need to be inset for drive wheels (because you probably could not sacrifice the wheelbase here) – so maybe same effective width as short side x pusher y pusher
Ideas • Low-velocity, wide, un-aimed shooter / pusher at one end of robot • High-velocity, focused, aimed kicker at the other end
Ideas • Non-overlapping “wings” folded on top of robot to act as “righters” should the robot overturn. • These could also provide hanging or lifting points for suspension