2012:Shooter and Collector

Shooter and Collector Master Task List

Task	Student	Mentor
Determine camera height needed to see basket targets from back of key over 6 ft robot near us when facing basket.	Need student	Jeff or Mr. Byers
Strategic Decide which side of robot turret "deadzone" will be on	Need strategy-tied student	Jeff
Determine all sensors (shooter, turret, wings), document them on Shooter team design page, and order	Need student	Daves, Jeff
Update battery mounting unit to remove compressor and to mount on back-side above frame rather than below	Tommy	Daves, Jeff
Start CAD model of electrical components/board	Need student	Daves, Jeff
Define class structure for "smart" shooter class	Peter	Jeff, Mr. Byers

Shooter Design

• Turret-mounted
  • Approx. 280 degrees of rotation minimum need final range
  • 1-degree precision
  • Mechanical hardstops
  • Absolute angular position sensor
    • Combination sensors - one on motor output shaft, one on turrent drive sprocket
  • Kit Window motor
  • Geared down 48:188
  • Controlled by speed controller (needed for fine adjustment)

• 2-Wheel shooter
  • Must be able to impart backspin
  • Fixed angle of shot -- approximately 70 degrees above floor
  • Each wheel independently controlled (to control backspin)
  • Powered by Fisher-Price (968-9013) motor on speed controllers
  • Transmission -- AM-0002
  • Sensor for RPM on each
    • Provide sufficient resolution for rapid speed control update
    • Identify sensor characteristics
    • If max ball velocity is 12m/s and if shooter wheel diameter is 6", then approx max rpm is 1500.

• Camera mounted on turret
  • Must have direct light source inline with lens
  • Must be able to tilt; does not need to be able to pan
  • Higher is better to see over robots in front of us

Beater Bar Design

• Fixed position within frame, as close to perimeter as possible
• 1 speed forward, 1 speed reverse
• Driven from a relay
• Pushes balls in and on to first conveyor section
• Banebots RS-775 motor
• Banebots P60 4-to-1 transmission, geared down 2-to-1 for total of 8-to-1

Wings/V-collector Design

• V-shaped collector outside of robot
• Articulated up/in and down/out -- 2-position motion
• Just a plain bars, no actual motion on the bars themselves
• Motion must be able to pull unloaded bridge down from horizontal
• Must extert 10lbs force at the tip to pull the unloaded bridge
• AM-0914 motor and associated gearbox
  • Geared down 2-to-1 for additional torque (2-to-1 gives stall torque of 6200 oz-lbs = 380 inch-lbs)
  • 2-to-1 gearing gives unloaded single-actuation of about 0.433 sec unloaded
  • Loaded (bridge) actuation is about 0.525 seconds
• Mechanical hard-stops
• Absolute positional sensor
• Limit switches on both ends

Ball Movement/Storage System Design

• 3-stage conveyor system
• First 2 stages straight at approx. 45 degree rise
• Intake end begins behind front wheel, about 1" from floor
• Each stage uses....
  • 1 Banebots RS-775 motors [1]
  • Coupled to Banebots P60 16-to-1 transmissions [2]
  • Controlled by Speed Controllers (could have been SPIKEs, but would be nice to be able to slow them for diagnostics)
  • Banner-style sensor at the very inside-edge to indicate that "this ball has advanced fully in this stage"
• Additional banner-style very close to intake end (just past beater bar contact point) to count balls and know when we can stop intake on beater bar

Resources

• Ball Trajectory Calculation spreadsheet
• Math behind the above spreadsheet
• Foil Sim III - Air flow simulator; useful for approximating drag effects on a ball
• Motor Specs from FIRST

Shooter and Collector's Engineering Notebook

Week 1

• 1/14

Week 2

• 1/15
• 1/17
• 1/18
• 1/19
• 1/21

Week 3

• 1/22
• 1/24
• 1/25
• 1/26
• 1/28

Week 4

• 1/29
• 1/31
• 2/01
• 2/02
• 2/04

Week 5

• 2/05
• 2/07
• 2/08
• 2/09
• 2/10
• 2/11

Week 6

• 2/12
• 2/13
• 2/14
• 2/15
• 2/16
• 2/17
• 2/18
• 2/19
• 2/20
• 2/21

Engineering Notebook Templates Available at:Engineering_Notebook_Template

Please Label All Notebook Pages 2012:Shooter and Collector XX.XX to avoid confusion.