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TRANSCRIPT
Building Systems and Mechanical Design
Robin Tan
Robotics Kits and Mechanical Systems
Hardware Design
Robot Management
Topic Outline
Robotics Kits – TETRIX System
Advantages
“Default” and by far the most popular
Tried and true
Wide Variety
Tough and robust
Screws stay in tightly
Diverse pattern of holes
Robotics Kits – TETRIX System
Disadvantages
Motors not as reliable
Parts are expensive per piece
Usually requires additional
cutting/drilling
Robotics Kits – MATRIX System
AdvantagesNumerous pre-drilled holes
(good for mounting)
Lighter
Relatively newer robotics kit
Robotics Kits – MATRIX System
Disadvantages
Metal components are flimsier
Plastic gears slip easily
Screw strip easily
Poor quality axles
Unreliable electronic systems
Less popular
Robotics Kits – Actobotics System
AdvantagesAbundance of holes allows for
precise construction
Compatible with different kits
Impressive gearing, servo, and bearing optionsCountless mounting
possibilities
Robotics Kits – Actobotics System
Disadvantages
Takes a long time to build
Reported problem with tight axles
Robotics Kits – 80/20 System
Advantages
Incredibly rigid
Easy to assemble
Good option for slides
Easy to make changes with
Robotics Kits – 80/20 System
Disadvantages
Heavier than TETRIX
Mechanical Design: Drivetrain
4-Wheel Drive 6-Wheel Drive Swerve Drive
Relative ManeuverabilityLess weight + partsLess wheels = less pushing
power
Impressive ManeuverabilityRequires more motorsHeavyExpensiveComplex
Greater turning abilityMore pushing powerHeavierHarder to travel over
bumps
Mechanical Design: Drivetrain
Omni Wheels Mecanum Wheels
Exceptional maneuverabilityFaster than Mecanum wheelsLess pushing powerComplex to drive
Exceptional maneuverabilityMore pushing power than Omni WheelsSlower than Omni WheelsComplex to program
Mechanical Design: Slide System
Wire-Pulley SystemSingle-Stage
Linear Slide System
Can be multi-stageWire/belt = less reliable
Extremely reliableSimple linear motionLess reach
Multi-StageLinear Slide System
Greater reachReliableHeavier
Mechanical Design: Types of Linear SlidesDrawer Slides
Thinner than 80/20Material is weaker
80/20 Slides
Heavy DutyMore ReliableMuch thicker – takes more roomMuch heavier
Robot Repair and Wire Management
Robot structure is designed to make electronics easy to fix
Wires run down the slides in Chain-Link WireCarriers to reduce possibilities of frayed wires
+ easy replacement
ALL WIRES are zip-tied – NO STRAY WIRESUSB Relief – Ensure reliable connection
Mechanical Reliability
Assigned an “inspection crew” after each component is constructed to inspect if it is durable enough for competitions
Test program/Checklist that is run before each match - ensure that the robot is functioning
Drilled holes - reduce weight
Attached shields and plows - passively push debris away
Duct tape applied all over robot - reduce static discharge
Mechanical Reliability
Anti-static polycarbonate sheets – reduce static buildup
Don’t connect your motors directly to your axles
Loctite shaft collars – make sure no axles fall out
Passive systems – reduce risk of electronic failure
Stress tests are calculated using PTC Mathcad