Computational Design + Fab: 4D Design

Jonathan Bachrach

EECS UC Berkeley

February 20, 2018

Today 1

Paper ReviewNews4D Basics4D Examples4D Kinematics

News 2

lab 5 due thursdayhave until march 8th plus late days to complete all labshow many projects?team mate for shaansign up for lightning project presentations starting next week

4D 3

articulated shapeslinkages

source HumongoNationphotogallery

Motivation 4

change motionamplify force

Links and Nodes 5

link: solid shapenode: attachment pointnumber of nodesexamples – binary, ternary, quaternary

binary ternary quaternary

Joints 6

constrained motion around pointsingle degree of freedom

theta

s

revolute prismatic

Revolute Implementations 7

cantelever clevis

Multiple DOF Joins 8

universal planar

Higher Pair DOF Joins 9

multiple revolute jointsprismatic + revolute joints

second-order-pin-joint pin-in-slot RP

Two Revolute Universal 10

Linkages 11

mechanical computershow do you program them?start with predicting outcomeslook at some examples

4D Examples 12

rudimentsmachineryautomotiveartisticrobotics

Cams 13

rotary cam linear cam

square cam irregular cam

Pulley 14

Direction Changing Pulley 15

Quick Return 16

Crank and Slider 17

Line Drawing 18

roberts chebyshev watts

Peaucellier Lipkin Linkage 19

source paulscottinfo.com

Vice Grips 20

Pantograph 21

Scissor Mechanism 22

Angutec 23

by Manfred Frank

Lamp 24

Mountain Bike Shock Absorber 25

source bikerumor.com

Small Back Hoe 26

Back Hoe 27

Specialty Back Hoe 28

Front Loader 29

Stewart Platform 30

Delta Mechanism 31

by Firepick

Klann Linkage 32

by Paul Klann

Strandbeest by Theo Jansen 33

Strandbeest by Theo Jansen on Beach 34

Strandbeest by Theo Jansen Videos 35

https://www.youtube.com/watch?v=MYGJ9jrbpvgstandbeestevolutiontheonjansen

https://www.youtube.com/watch?v=HLkd1xXrie0theojansenmechanisminsolidworks

Kinematics 36

forward kinematics go from joint parameters to positionsinverse kinematics go from positions to joint parameters

Next Time 37

4D Work and Torque4D Closed Chains

References 38

Design FUNdaMENTALS: Linkages by Alexander Slocum507 Mechanical Movements: Mechanisms and Devices by Henry T.Brown