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