Paul E. Sandin - Robot Mechanisms and Mechanical Devices Illustrated

Robot Mechanismsand MechanicalDevices IllustratedPaul E. SandinMcGraw-HillNew York | Chicago | San Francisco | Lisbon | London | MadridMexico City | Milan | New Delhi | San Juan | Seoul | Singapore | Sydney | TorontoCopyright © 2003 by The McGraw-Hill Companies, Inc. All rights reserved. Manufactured in the United States of America.Except as permitted under the United States Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of thepublisher.0-07-142928-XThe material in this eBook also appears in the print version of this title: 0-07-141200-XAll trademarks are trademarks of their respective owners. Rather than put a trademark symbol after every occurrence of atrademarked name, we use names in an editorial fashion only, and to the benefit of the trademark owner, with no intentionof infringement of the trademark.

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You may use the work for your own noncommercial and personal use; any other useof the work is strictly prohibited. Your right to use the work may be terminated if you fail to comply with these terms.THE WORK IS PROVIDED “AS IS”. McGRAW-HILL AND ITS LICENSORS MAKE NO GUARANTEES OR WARRANTIES AS TO THE ACCURACY, ADEQUACY OR COMPLETENESS OF OR RESULTS TO BE OBTAINED FROMUSING THE WORK, INCLUDING ANY INFORMATION THAT CAN BE ACCESSED THROUGH THE WORK VIAHYPERLINK OR OTHERWISE, AND EXPRESSLY DISCLAIM ANY WARRANTY, EXPRESS OR IMPLIED,INCLUDING BUT NOT LIMITED TO IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. McGraw-Hill and its licensors do not warrant or guarantee that the functions contained in the workwill meet your requirements or that its operation will be uninterrupted or error free.

Neither McGraw-Hill nor its licensorsshall be liable to you or anyone else for any inaccuracy, error or omission, regardless of cause, in the work or for any damages resulting therefrom. McGraw-Hill has no responsibility for the content of any information accessed through the work.Under no circumstances shall McGraw-Hill and/or its licensors be liable for any indirect, incidental, special, punitive, consequential or similar damages that result from the use of or inability to use the work, even if any of them has been advisedof the possibility of such damages. This limitation of liability shall apply to any claim or cause whatsoever whether suchclaim or cause arises in contract, tort or otherwise.DOI: 10.1036/007142928XFor Vicky, Conor, and AlexThis page intentionally left blank.For more information about this title, click here.ContentsIntroductionxiAcknowledgmentsChapter 1Motor and Motion Control SystemsIntroductionMerits of Electric SystemsMotion Control ClassificationClosed-Loop SystemTrapezoidal Velocity ProfileClosed-Loop Control TechniquesOpen-Loop Motion Control SystemsKinds of Controlled MotionMotion InterpolationComputer-Aided EmulationMechanical ComponentsElectronic System ComponentsMotor SelectionMotor Drivers (Amplifiers)Feedback SensorsInstallation and Operation of the SystemServomotors, Stepper Motors, and Actuators forMotion ControlPermanent-Magnet DC ServomotorsBrush-Type PM DC ServomotorsDisk-Type PM DC MotorsCup- or Shell-Type PM DC MotorsPosition Sensing in Brushless MotorsBrushless Motor AdvantagesBrushless DC Motor DisadvantagesCharacteristics of Brushless Rotary ServomotorsLinear Servomotorsxxxv134557899101011151618192020212223242930313131vCopyright © 2003 by The McGraw-Hill Companies, Inc.

Click here for Terms of Use.viContentsCommutationInstallation of Linear MotorsAdvantages of Linear vs. Rotary ServomotorsCoil Assembly Heat DissipationStepper MotorsPermanent-Magnet (PM) Stepper MotorsVariable Reluctance Stepper MotorsHybrid Stepper MotorsStepper Motor ApplicationsDC and AC Motor Linear ActuatorsStepper-Motor Based Linear ActuatorsServosystem Feedback SensorsRotary EncodersIncremental EncodersAbsolute EncodersLinear EncodersMagnetic EncodersResolversTachometersLinear Variable Differential Transformers (LVDTs)Linear Velocity Transducers (LVTs)Angular Displacement Transducers (ATDs)InductosynsLaser InterferometersPrecision Multiturn PotentiometersSolenoids and Their ApplicationsSolenoids: An Economical Choice for Linear or Rotary MotionTechnical ConsiderationsOpen-Frame SolenoidsC-Frame SolenoidsBox-Frame SolenoidsTubular SolenoidsRotary SolenoidsRotary ActuatorsActuator CountDebuggingReliabilityCostChapter 2BeltsIndirect Power Transfer Devices34353637373838384041424343444647484951535555575759606062636363646466676768686972ContentsFlat BeltsO-Ring BeltsV-BeltsTiming BeltsSmoother Drive Without GearsPlastic-and-Cable ChainChainLadder ChainRoller ChainRack and Pinion Chain DriveTiming or Silent ChainFriction DrivesCone Drive Needs No Gears Or PulleysGearsGear TerminologyGear Dynamics TerminologyGear ClassificationWorm GearsWorm Gear with Hydrostatic EngagementControlled Differential DrivesTwin-Motor Planetary Gears Provide Safety Plus Dual-SpeedHarmonic-Drive Speed ReducersAdvantages and DisadvantagesFlexible Face-Gears Make Efficient High-Reduction DrivesHigh-Speed Gearheads Improve Small Servo PerformanceSimplify the MountingCost-Effective AdditionChapter 3Direct Power Transfer DevicesCouplingsMethods for Coupling Rotating ShaftsTen Universal Shaft CouplingsHooke’s JointsConstant-Velocity CouplingsCoupling of Parallel ShaftsTen Different Splined ConnectionsCylindrical SplinesFace SplinesTorque LimitersTen Torque-LimitersOne Time Use Torque Limiting7373737576777980808282838485878888909093959699100102102104107109110114114115117118118120121121125viiviiiContentsChapter 4Wheeled Vehicle Suspensions and DrivetrainsWheeled Mobility SystemsWhy Not Springs?Shifting the Center of GravityWheel SizeThree-Wheeled LayoutsFour-Wheeled LayoutsAll-Terrain Vehicle with Self-Righting and Pose ControlSix-Wheeled LayoutsEight-Wheeled LayoutsChapter 5Steering HistorySteering BasicsThe Next Step UpChapter 7130130131134136141144150155Tracked Vehicle Suspensions and Drive Trains 161Steering Tracked VehiclesVarious Track Construction MethodsTrack ShapesTrack Suspension SystemsTrack System LayoutsOne-Track Drive TrainTwo-Tracked Drive TrainsTwo-Tracked Drive Trains with Separate Steering SystemsFour-Tracked Drive TrainsSix-Tracked Drive TrainsChapter 6127167168171174178178179180181184187190193Walkers199Leg ActuatorsLeg GeometriesWalking TechniquesWave WalkingIndependent Leg WalkingFrame WalkingRoller-WalkersFlexible Legs202203208208208211214214ContentsChapter 8Pipe Crawlers and Other Special CasesHorizontal CrawlersVertical CrawlersTraction Techniques for Vertical Pipe CrawlersWheeled Vertical Pipe CrawlersTracked CrawlersOther Pipe CrawlersExternal Pipe VehiclesSnakesChapter 9Comparing Locomotion MethodsWhat Is Mobility?The Mobility SystemSizeEfficiencyThe EnvironmentThermalGround CoverTopographyObstaclesComplexitySpeed and CostThe Mobility Index Comparison MethodThe Practical MethodExplain All This Using the Algebraic MethodChapter 10Manipulator GeometriesPositioning, Orienting, How Many Degrees of Freedom?E-ChainSlider CrankArm GeometriesCartesian or RectangularCylindricalPolar or SphericalThe WristGrippersPassive Parallel Jaw Using Cross TiePassive Capture Joint with Three Degrees of Freedom217220221222223224224226226227229229230231232232233233234235235236236237239241243243245246247248250252255256ixxContentsIndustrial RobotsIndustrial Robot AdvantagesTrends in Industrial RobotsIndustrial Robot CharacteristicsChapter 11Proprioceptive and Environmental SensingMechanisms and DevicesIndustrial Limit SwitchesLayoutsCombination Trip (Sense) and Hard StopBy-Pass LayoutsReversed BumpBumper Geometries and SuspensionsSimple Bumper Suspension DevicesThree Link PlanarTension Spring StarTorsion Swing ArmHorizontal Loose Footed Leaf SpringSliding Front PivotSuspension Devices to Detect Motions in All Three PlanesConclusionIndex258259259261263270276277278279280282283284284285286287289291IntroductionThis book is meant to be interesting, helpful, and educational to hobbyists, students, educators, and midlevel engineers studying ordesigning mobile robots that do real work.

It is primarily focused onmechanisms and devices that relate to vehicles that move around bythemselves and actually do things autonomously, i.e. a robot. Making avehicle that can autonomously drive around, both indoors and out,seems, at first, like a simple thing. Build a chassis, add drive wheels,steering wheels, a power source (usually batteries), some control codethat includes some navigation and obstacle avoidance routines or someother way to control it, throw some bump sensors on it, and presto! arobot.Unfortunately, soon after these first attempts, the designer will findthe robot getting stuck on what seem to be innocuous objects or bumps,held captive under a chair or fallen tree trunk, incapable of doing anything useful, or with a manipulator that crushes every beer can it tries topick up. Knowledge of the mechanics of sensors, manipulators, and theconcept of mobility will help reduce these problems.