proe mechanism notes

8/20/2019 ProE Mechanism Notes

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Introduction to the Mechanism Design Process

Module Overview

This module is an overview of functionality used within Pro/ENGINEER for the

design of complex mechanisms.

In this module you learn the typical process used to design mechanism withinPro/ENGINEER and the mechanism design extension. !ost companies use thisprocess" however your specific company process may differ.

Objectives

#fter successfully completing this module you will $e a$le to%

• &nderstand and descri$e mechanism design.

• &nderstand and descri$e tools availa$le in the !echanism 'esign Extension.

• &nderstand and descri$e a typical Pro/ENGINEER mechanism design process.

Introduction to Mechanism Design

The !echanism 'esign extension ena$les you to simulate (inematic motion in your

Pro/ENGINEER assem$lies.

!echanism 'esign Extension )!'*+ ena$les you to%

• 'efine mechanism connections $etween components.

• !ove the connected components using servo motors.

• !easure changes in position velocity and acceleration.

• 'etect and identify collisions $etween moving components.

• ,reate trace curves and motion envelopes.

The !echanism Environment consists of the%

• !echanism Tree.

• !otion and 'ynamics tool$ars.

Introduction to Mechanism Design — Theory

The !echanism 'esign Extension )!'*+ is included in every seat of Pro/ENGINEER.This module is integrated within the assem$ly environment and ena$les you tocreate (inematics design studies of your assem$lies.

&sing !'* you can do the following%

• 'efine mechanism connections $etween components.

• !ove the connected components using servo motors.

• !easure changes in position velocity and acceleration.

• 'etect and identify collisions $etween moving components.

• ,reate trace curves and motion envelopes.

The !echanism 'ynamics -ption )!'-+ is reuired to simulate



gravity force motors springs dampers and forces/torues. This

functionality will $e covered in the !echanism imulation usingPro/ENGINEER 0ildfire 1.2 course.

The !echanism Environment

3ou access the !echanism environment $y clic(ing Applications > Mechanism from the

main menu. The !echanism environment is made up of a !echanism Tree which islocated under the main model tree and the !otion and 'ynamics tool$ars locatedalong the right side of the main window. These tool$ars contain icons specific to the

!echanism environment.

Understanding the Mechanism Design Process

The following steps are used in a typical mechanism design process.

!echanism 'esign0or(flow%

• ,reating the model.

• 4erifying themechanism.

• #dding mechanismentities.

•

Preparing foranalysis.

• #naly5ing themechanism.

• Evaluating results.

• Running post6!'*processes.

#dding a !echanism ,onstraint

4erifying the !echanism

#dding !echanism Entities

if you prefer to read Lecture Notes, Click here

Understanding the Mechanism Design Process — Theory

The following steps are used in a typical mechanism design process. Note that someof these points are optional and the process will vary depending on the needs of yourproduct and organi5ation.

• ,reating the model.

• 4erifying the mechanism.

• #dding mechanism entities.

• Preparing for analysis.

• #naly5ing the mechanism.

• Evaluating results.

• Running post6!'* processes.

The optional points include Running post6!'* processes as well ascertain tas(s in Evaluating results.



4erifying the !echanism

4erifying the !echanism 8 Theory

#fter you create your model you verify its motion. This is an important step $ecause

it ensures that the connections produce the desired motion on the parts with

respect to each other.

3our mechanism can $e verified using one of the following methods%

• Reconnect 8 Run an assem$ly analysis $y clic(ing Reconnect from themain tool$ar or Edit 9 Reconnect. This process is also (nown as ;connecting

the assem$ly.< If your assem$ly is already connected running an assem$lyanalysis does not move your mechanism.

'rag 8 &se Point 'rag to open the 'rag dialog $ox and interactively drag

components of the assem$ly. &se 7ody 'rag to study the general nature of howyour mechanism can move and the extent to which $odies can $e positioned. &se theoptions in the 'rag dialog $ox to disa$le connections glue $odies and apply

geometry constraints to o$tain a specific configuration. 3ou can then record theseconfigurations as snapshots for later reference.

Adding Servo Motors

&se servo motors to define the mechanism=s desired a$solute motion.

3ou can add servo motors to%

• !otion axes of a connection.

• Geometric entities of a component.

# !otor #pplying >inear !otion # !otor #pplying Rotational !otion

#dding ervo !otors 8 Theory

3ou add servo motors to specify position velocity or acceleration of a mechanism.

#dding ervo !otors

#fter you create your model and verify the connections that ena$le it to move

correctly you can add servo motors to drive the model=s motion. 3ou use the servo

motors to define the mechanism=s desired position velocity or acceleration.

# servo motor moves your model to satisfy the specified position velocity oracceleration reuirements without regard for the forces needed or for interference

$etween $odies. 7ecause a servo motor defines the a$solute rotational ortranslational motion of a motion axis the motion axis loses the degree of freedom)'-?+ associated with that motion.



3ou can add servo motors to%

• !otion axes of a connection.

• Geometric entities of a component.

ervo motors were called 'rivers in previous releases of !echanism'esign. The !echanism 'ynamics -ption )!'-+ is reuired to addadditional mechanism entities such as gravity force motors springs

dampers forces and torues.

Preparing for Analysis of a Mechanism

'efine the mechanism=s

initial position andmeasures that must $e

evaluated during theanalysis run.Prepare for

analysis%

• 'efine initialposition.

• ,reate measures.

#dd measures to evaluate%

• Position.

• 4elocity.

• #cceleration.

#naly5ing Position

#naly5ing #cceleration



Preparing for #nalysis of a !echanism 8 Theory

7efore performing an analysis on a model you must prepare for the analysis$y first defining the initial position that the analysis will $egin from. It is also

important to define measures that will $e evaluated as the mechanismanalysis is run through the defined motion.

'efining the Initial Position

The initial position of a mechanism can $e defined $y assigning regeneration

values to the motion axis definitions of its connections. Regenerating themodel will then move the mechanism to that defined position. Initial

position can also $e defined $y using tools in the 'rag dialog $ox.

,reating !easures

3ou define measures $efore running an analysis $ecause they are then

evaluated as the mechanism analysis moves the mechanism through its

defined motion. !easures are important $ecause they can help youunderstand and analy5e the results of moving a mechanism and provideinformation that you can use to improve the mechanism=s design.

3ou can create measures to evaluate position velocity or acceleration forpoints or motion axes in your assem$ly.

Analying the Mechanism

#naly5e your mechanism per its defined connections selected servo motors andpreferences.

Types of #nalysis%

• Position #nalysis

• @inematic #nalysis

'efine Preferences and

!otors%

• 'efine Preferences

• >oc( 7odies

• 'efine !otors

@inematic #nalysis at Initial Position

@inematic #nalysis at ?inal Position



#naly5ing the !echanism 8 Theory

#n analysis is run on a mechanism $y first selecting the type of analysis to run andthen setting the analysis preferences and motors.

Types of #nalysis

0hen analy5ing the mechanism you must select the type of analysis to run.

• ,reate a Position #nalysis 8 # position analysis ena$les you to analy5ewhether your mechanism can assem$le under the reuirements of the appliedservo motors and connections. In previous releases of Pro/ENGINEERposition analysis was also named Repeated #ssem$ly and @inematic analysis.

• ,reate a @inematic #nalysis 8 # (inematic analysis ena$les you to review the

motion of your model as imposed $y servo motors. 3ou can also use a(inematic analysis as the first step in your design process to locate

interference or points where the assem$ly analysis fails.

3ou will also see 'ynamic tatic and ?orce 7alance analysis types inthe Type drop6down list" however the !echanism 'ynamics -ption

)!'-+ is reuired to run these analysis types.

'efining Preferences and !otors

#fter you select an analysis type you then do the following%

• 'efine Preferences 8 'epending on the type of analysis you create you need

to define the preferences of the analysis. These preferences include the timedomain which ena$les you to determine how Pro/ENGINEER records motionover time.

• >oc( 7odies 8 3ou may loc( $odies and connections so they remain fixedduring the analysis.

• 'efine !otors 8 3ou can use the motors ta$s to ena$le/disa$le specific servomotors.

The external loads ta$ is disa$led unless you have an !'- license

$ecause you cannot simulate external force/torue loads friction orgravity in !'*.

!valuating Analysis "esults

Evaluate the results of your analysis to ensure mechanism design will functionproperly.

#nalysis Results%

• #nalysis Results Play$ac(

• Interference ,hec(

• !easures and Graphs

• ,reate Trace ,urves

• ,reate !otion Envelopes

4iew the !echanism in !otionIdentify Interferences



Evaluating #nalysis Results 8 Theory

#fter running an analysis the results of the analysis should $e reviewed to ensure themechanism will function properly. The results of an analysis should $e reviewed using the

following tools%

#nalysis Results Play$ac( 8 7y running an analysis play$ac( you can review yourmechanism model in motion. 3ou can use the Play$ac(s dialog $ox to save restore

remove and export your analysis results. #fter you run an analysis you can save theresults as a play$ac( file and run them in another session.

• Interference ,hec( 8 3ou can also run the analysis play$ac( to chec( for

interferences $etween moving part models.

•

!easures and Graphs 8 7y reviewing measures and generating graphs you candetermine the position velocity and acceleration of your mechanism modelsthroughout their range of motion.

• ,reate Trace ,urves 8 # trace curve graphically represents the motion of a point or

vertex relative to a part in your mechanism. Trace curves can $e used to create camprofiles slot curves and solid geometry.

• ,reate !otion Envelopes 8 # motion envelope is a volumetric representation of themoving components of your mechanism.

Creating Mechanism Connections

Module OverviewIn this module you learn to define motion in an assem$ly $y assem$ling andconfiguring components using various predefined mechanism connection sets.

Objectives

#fter successfully completing this module you will $e a$le to%

• ,reate mechanism $odies.

• &nderstand constraints and connection sets.

• &nderstand predefined connection sets.

• ,onfigure motion axis settings.

• &se Rigid connection sets.

• &se Pin connection sets.

• &se lider connection sets.

• &se ,ylinder connection sets.

• &se Planar connection sets.

• &se 7all connection sets.

• &se 0eld connection sets.

• &se 7earing connection sets.

• &se General connection sets.

• &se lot connection sets.

• ,reate ,am6?ollower connections.

• &se A' contact.

• ,reate Generic gear connections.

• ,reate 'ynamic gear connections.

• ,reate 7elt connections.

• &se the 'rag and napshot tools.



&ser6'efined ,onstraints%

• #ssem$le components to formmechanism $odies.

• #lso called standard assem$ly

constraints.• Includes constraints such as !ate

#lign and Insert.

• Predefined ,onnection ets%

• #ssem$le components $y

constraining motion along axesplanes and curves.

• #lso called mechanism connectionsets.

• Includes connections such as Pin

,ylinder and lider.

7arrel 7olt #ssem$ly

&nderstanding ,onstraints and ,onnections 8 Theory

,onstraints define the fixed position of a component while connection sets constrainthe motion of a component.

&ser6'efined ,onstraints

3ou use standard constraints to assem$le individual models to form $odies in

mechanisms. These $odies act as a single unit and do not move in relation to oneanother.

In the $arrel $olt assem$ly shown the $rown $ase gold $arrel and four screws are

assem$led using user6defined constraints such as !ate and Insert. Thesecomponents do not move in relation to one other $ecause they have $eenconstrained so all degrees of freedom )'-?+ are removed. These components formthe ground $ody of the mechanism.

&ser6defined constraints were also used to assem$le the gray $olt and handle partsthat slide in this mechanism. These two components form the second $ody of the

mechanism.

&ser6defined constraints can also $e referred to as standard assem$lyconstraints.

Predefined ,onnection ets

,onnection sets assem$le components $y constraining motion along certain axes

planes and curves. ,omponents assem$led with connections are free to rotate

and/or translate a$out one another. Pin ,ylinder lot and Planar are examples ofconnection sets availa$le in Pro/ENGINEER.

,onnection sets are important $ecause they ena$le you to free certain degrees of

freedom )'-?+. Thus connection sets are not rigid and ena$le you to impart realistic

motion on your models. In the $arrel $olt assem$ly shown a lot connection set isused to define the motion of the $olt and handle $ody as it moves through themechanism.

Predefined connection sets can also $e referred to as mechanism

connection sets.Understanding Predefined Connection Sets

Predefined connection sets constrain the motion of a component while stillpermitting various degrees of freedom.



Type Total '-? Rotation Translation

Rigid2 2 2

Pin C C 2

liderC 2 C

,ylinderD C C

PlanarA C D

7allA A 2

0eld2 2 2

7earing A C

General4aries 4aries 4aries

FdofF A A

lot4aries 4aries 4aries

nderstanding Predefined Connection Sets — Theory

There are several different types of predefined connection sets in Pro/ENGINEER. The table

displays each connection set type and the degrees of freedom in the set.

Before selecting a predefined connection set, yo mst nderstand ho! placement

constraints and degrees of freedom are sed to define movement. Then yo can select thecorrect connections to define yor mechanisms.

The Total DOF column displays the connection's total number of degrees of

freedom. The Rotation and Translation columns then break down the allowed

motion of the mechanism in those terms.

Using Predefined Connection Sets

"elect a predefined connection set from the Predefined #onnection "et list in the

#omponent Placement dashboard in $ssembly mode. %se the connection sets to positioncomponents and define movement in yor assembly. Predefined connection sets serve threeprposes&

'. (efine !hich placement constraints are sed to place the component in the model.

). Restrict the motion of bodies relative to each other, redcing the total possible

degrees of freedom *(+- of the system.

. (efine the ind of motion a component can have !ithin the mechanism.

Configuring Motion Axis Settings

%se motion a0is settings to control the movement of componentconnections.

Motion Axis Settings:

• Regen 1ale

• 2ero Position

• 3inimm and 3a0imm 4imits

• (ynamic Properties

Regenerated Position



Using Pin Connection Sets

%se the Pin connection set to assemble a component !ith only a

rotational degree of freedom.

Using Rigid Connection Sets — Theory

Rigid connection sets are used to connect two components so they do not move relative to one another.

Components connected in such a way become a single body.

Similar to the User Defined assembly constraint set, a Rigid connection set uses any valid combination of

standard assembly constraints such as Mate, Align, and Insert to constrain the position of a component. Rigid

connections enable you to group any valid set of assembly constraints into the connection set. These constraints

can be a fully constrained set or a partially constrained subset.

Motion Eliminated

You cannot use a rigid connection set to connect multiple bodies of a sub-assembly and still maintain motion inthat sub-assembly. When using a rigid connection to assemble a sub-assembly with Mechanism Design

connections to a master assembly, the sub-assembly will be considered as a ground body and will lose itsinternal motion.

In the assembly shown, if the piston sub-assembly is constrained using a Rigid

connection set at each end of the piston sub-assembly (referencing both

components of the sub-assembly), the motion in the sub-assembly will be lost.

A Weld connection set should be used in situations where multiple components

need to be constrained but motion must be retained.

Pin Connection Sets:

• $0is $lignment ; #onstraint

• Translation ; #onstraint

• Rotation $0is ; 3otion $0is

A Pin Connection

if you prefer to read Lecture Notes, Click here

Using Pin Connection Sets — Theory

A Pin connection set is used to connect a component to a referenced axis so the component rotates ormoves along this axis with one rotational degree of freedom.

Using Pin Connection Sets

A Pin connection set contains two constraint settings and one rotation axis setting:

• Axis Alignment 6 This constraint defines the a0is that the component isaligned to and rotates abot. The reference can be a selected a0is, edge,

crve, or cylindrical srface.

• Translation 6 This defines the component<s position along the alignment a0is.

The reference can be a selected datm point, verte0, datm plane, or planarsrface.

• Rotation Axis 6 This is the rotational motion a0is element of the connectionset. 5o se it to define rotational motion settings for the connection sch asthe 7ero position, regenerated position, minimm limits, and ma0imm limits.



Using Slider Connection Sets

%se the "lider connection set to assemble a component !ith only atranslational degree of freedom.

Slider Connection Sets:

• $0is $lignment ; #onstraint

• Rotation ; #onstraint

• Translation $0is ; 3otion $0is

A Slider Connection

Using Slider Connection Sets — Theory

$ "lider connection set is sed to connect a component to a referenced a0is so the

component slides or moves normal to this a0is !ith one translational degree of freedom.

Using Slider Connection Sets

$ "lider connection set contains t!o constraint settings and one translation a0is setting&

• Axis Alignment 6 This constraint defines the a0is that the component slides along.

The reference can be a selected a0is, edge, crve, or cylindrical srface.

• Rotation 6 This constraint restricts the components rotation along the a0is of

alignment. The reference can be a selected datm plane or other planar srface.

• Translation Axis 6 This is the translational motion a0is element of the connection

set. 5o se it to define translational motion settings for the connection sch as the

7ero position, regenerated position, minimm limits, and ma0imm limits.

Using Cylinder Connection Sets

%se the #ylinder connection set to assemble a component !ith rotationaland transitional degrees of freedom.

Cylinder Connection Sets:

• $0is $lignment ;#onstraint

• Translation $0is ; 3otion$0is

• Rotation $0is ; 3otion

$0is

A Cylinder Connection



eep the follo!ing points in mind !hen defining and sing cam>follo!er connections&

• Pro/ENGINEER defines cams as e0tending infinitely in the e0trsion direction.

• $ cam>follo!er connection does not prevent the cam from tipping. 8hen re=ired,add additional constraints to prevent parts from tipping.

• Each cam can have only one fol lo!er. If yo !ant to model a cam !ith mltiple

follo!ers, yo mst define a ne! cam>follo!er connection for each ne! pair.• Try to avoid a design !ith a connection along a straight line in the !oring plane.

0D Contact

( #ontact simlates contact bet!een bodies in three>dimensionalmotion.

3D Contact:

• Is based on real materialproperties.

• %ses static and sliding friction.

3D Contact

0D Contact

%sing ( #ontact yo can simlate contact bet!een bodies in three>dimensional motion.

The system incldes static and sliding friction in its calclations, !hich are based on real

material properties sch as Poisson<s ratio, 5ong<s modls, and a damping coefficient. (contact can be defined from a single analytical srface sch as a spherical, cylindrical, orplanar srface to mltiple other analytical srfaces. #ontact can also be defined from averte0 to other srfaces. The three>dimensional contact is also active !hile dragging.

In the figre, ( contact is sed to simlate dropping a rbber cbe into a bo0 to visali7ethe cbe boncing and rotating, and coming to rest.

Creating 'eneric 'ear Connections

#aptre any Rotational or 4inear relationship sing Generic gear

connections.



• Generic gear definition options&

o

Pitch circle diameters

o Enter ratio vales

• 3otion relationships&

o Rotational/Rotational

o

Rotational/4inear

o 4inear/Rotational

o

4inear/4inear

Gear Example

Rotational/Linear Example

Creating 'eneric 'ears

5o can create a generic type gear connection to captre any rotational or linear

relationship bet!een components. 8hen sing the generic gear type, yo are able tospecify either t!o pitch circle diameters, or motion ratio vales.

Generic gears can be se to create a simple gear train bt, nl ie dynamic gear types,generic gear components do not actally have to toch. Therefore, they can be located in

different locations !ithin the assembly, enabling yo to create rotational and/or linearrelationships bet!een any set of components.

5o can captre the follo!ing motion relationships sing generic gears&

• Rotational/Rotational

• Rotational/4inear

• 4inear/Rotational

• 4inear/4inear

Creating Dynamic 'ear Connections

#reate different types of common gear connections.



• Types

o

"pr

o Bevel

o Rac and Pinion

o 8orm

•

Gear Properties

o Pitch (iameter

o

Pressre $ngle

o 9eli0 $ngle

o Bevel $ngle

o "cre! $ngle

• 3echanism $nalysis

o inematic or (ynamic

Spur Gears

Bevel Gears

Worm Gears Rack and Pinion Gears

Creating Dynamic 'ear Connections

5o can create gear connections in 3echanism mode that tili7e manfactring tooth angles

to determine their motion properties. Properties sch as pitch diameter, pressre angle,heli0, bevel, and scre! angles are sed to compte motion, as !ell as inematic and

dynamic analyses. (ynamic analyses can inclde reaction forces based on the toothgeometry at the location !here the pitch diameters meet. The system can atomatically

calclate pitch circle diameters and bevel angles.

E0amples of the for dynamic gear types inclde&

•

"pr 6 T!o meshing gears rotating on parallel a0es.• Bevel 6 $ pinion gear driving a cro!n gear on perpendiclar a0es.

• Rac and Pinion 6 $ pinion gear meshing !ith a sliding rac gear.

• 8orm 6 $ !orm shaft rotating a pinion on perpendiclar a0es.

(ynamic gears also have several properties yo can define&

• Pitch (iameter 6 "pecify a pitch diameter for the first gear in the pair, and thecorresponding pitch diameter is atomatically calclated. 5o can also se the %ser(efined option to manally inpt both vales or the ratio manally.

• Pressre $ngle 6 $ gear tooth pressre angle for all gear types.

•

9eli0 $ngle 6 $ gear tooth 9eli0 angle for "pr, Bevel, and Rac and Pinion gears.• Bevel $ngle 6 (etermined atomatically for Bevel Gears based on geometry.

• "cre! $ngle 6 (efines the scre! angle for !orm gears.

• Icon 4ocation 6 (efines a plane to display and calclate the gear connection.

Once defined, you can simply press CTRL + ALT to drag gears in Standard

Assembly mode or in Mechanism mode.

You can also click Drag Components to drag connected components with

additional options, such as creating snapshots.

Creating $elt Connections

#reate belts that connect plleys to create and analy7e motion.



• #onnect plleys for rotation

o

Planar belt path

o Belt length

o Belt fle0ibility

• #reate belt model

o

rom belt crve

Original Model

Belt Created Belt Modified

Creating $elt Connections

In 3echanism mode, yo create belts in a planar path that connect plleys to transmit

rotation. Belt length and fle0ibility can be controlled. +nce a belt connection is defined, yo

can create a part model containing the belt crve. rom this crve yo can create solidgeometry to represent the belt.

Belts have several options&

• Belt (irection 6 Indicates on !hich side the belt travels arond the plley.

•

Plley (iameter 6 By defalt is coincident to the selected plley srface. 5o canalso enter a vale from the dashboard or on>screen leaders.

• Nmber of 8raps 6 Indicates the nmber of !raps the belt shold tae arond theplley. The defalt is ' !rap.

• Belt 4ength 6 Belts defalt to a natral length defined by the belt path. 5o can thenspecify a fi0ed length.

• Belt Plane 6 $ selected plane that defines the centerline of the belt path.

• le0ibility 6 Indicates a set vale for the EC$ parameter. *5ongs 3odls mltipliedby cross>section area.-

• Body (efinition 6 Indicates !hich body is defined as the moving plley body verssthe stationary carrier body.

You can perform kinematic and dynamic analyses of belts and pulleys inMechanism mode.

Using the Drag and Sna!shot Tools

%se the drag and snapshot tools to move and save yor mechanism invarios positions.



on and off by selecting or clearing the chec bo0 ne0t to the constraint. %se the shortctmen to copy, ct, paste, or delete the constraint.

• Align 6 "elect t!o points, t!o lines, or t!o planes. The entities remain aligneddring the dragging operation.

• Mate 6 "elect t!o planes. The planes remain mated dring the draggingoperation.

• 2rient 6 "elect t!o planes to orient at an angle to each other.

• Motion Axis Constraint 6 "elect a motion a0is to specify motion a0isposition. 5o can define mltiple constraints for the same motion a0is. 9o!ever, only

one can be enabled at any given time.

• $ody($ody oc- 6 "elect bodies to be loced together.

• .na/le3Disa/le Connections 6 "elect a connection. The connection is

disabled.

• Reconnect 6 (efine the offset vale for any mate or align constraints. (efinea vale for angle or distance, i f yo have chosen an orientation constraint.

To delete a selected constraint from the list, clic Delete Constraint .

,onfiguring !otion and #nalysis

!odule -verview

In this module, you learn basic concepts of servo motors and how they apply motion to amechanism. You learn how an analysis is used to run the motion applied by motors in the

mechanism. You learn how to create both geometry and motion axis type servo motors. You

learn how to configure servo motors and use functions to assign various magnitudes of motion.

Finally, you graph the magnitude of each motor and run an analysis to verify the magnitude of

motion.

-$:ectives

After successfully completing this module, you will be able to:

• Understand servo motors.

• Understand analysis definitions.

•

Create geometry servo motors.

• Create motion axis servo motors.

• Create slot motors.

• Graph the magnitude of servo motors.

• Assign constant motion to a servo motor.

• Assign ramp motion to a servo motor.

• Assign cosine motion to a servo motor.

• Assign SCCA motion to a servo motor.

• Assign cycloidal motion to a servo motor.

• Assign parabolic motion to a servo motor.

• Assign polynomial motion to a servo motor.

•

Assign table-defined motion to a servo motor.



o Motion Direction — If a point was selected as the Reference Entity, an

additional reference must be selected to define the direction of motion.

o Flip — Changes the direction of the servo motor's motion.

o Motion Type — The motion type defines the motion of the geometry motor as

being translational or rotational.

You use the Profile tab of the Servo Motor Definition dialog box to define specification for themotor.

• Specifications — Define the type of movement the servo motor will produce:

o Click Motion Axis Settings to edit settings for the selected motion axis. This

includes Current Position, Regen value, Minimum Limit, and Maximum Limit.

o Position — Specify the servo motor motion in terms of the position of a selected

reference entity.

o Velocity — Specify the servo motor motion in terms of its velocity.

o Acceleration — Specify the servo motor motion in terms of its acceleration.

o

Initial Position — Defines the starting position for your servo motor and appearsonly if Velocity or Acceleration is selected. If you want to specify another Initial

Position, clear the Current check box and specify the value at which the motion

should start.

o Initial Velocity — Defines the velocity of the servo motor at the beginning of the

analysis and appears only if Acceleration is selected.

o Magnitude — Defines the magnitude of the motor as a function of time. It can be

a constant value, or it can be defined by one of the functions you select. The

function is used to generate the magnitude of the motor based on the time period

the analysis is run. For example, a translational Position motor using the Ramp

function (q=A+B*t) will move a body 40 units, if A=0, B=10, and the analysis is

run for 4 seconds.o Graph — Enables you to generate and display a graph plotting the Position,

Velocity, and Acceleration generated by your motor over time. This is a very

useful tool for determining how a defined velocity or acceleration affects the

position of a component in a mechanism, prior to actually running an analysis.

&nderstanding #nalysis 'efinitions

Use analyses to record and display the motion of your mechanism over time.

Preferences:

• Analysis Type # !osition or $inematic

• Graphical %isplay Settings

• &oc'ed (ntities

• )nitial Configuration

Motors:

• Select Motors to un

• Start and (nd Times !er Motor

Analysis Displayed at Start

Analysis Displayed at End



,reating !otion #xis ervo !otors

Use motion axis servo motors to define motion in the direction of a connection's motion axis.

Motion Axis Servo Motors

• About a otational Axis

• Along a Translational Axis

• Along a Slot Connection

Motor Profiles

•

Specification• )nitial !osition

• Magnitude

• Graph

Translational and Rotational

The Profile tab in the Servo Motor Definition box is where the motor's specifications are defined.

• Specification — The motor is controlled by Position, Velocity, or Acceleration.

• Initial Position — You can set the initial position of the motor (but not for Position motors).

• Magnitude — You can define the magnitude of motion using one of nine different types, including

Constant and Ramp.

•

Graph — You can graph the motor's Position, Velocity, and Acceleration.

Creating Motion Axis Servo Motors — Theory

You use motion axis servo motors to define a motor with motion in the remaining degree of

freedom contained in a connection. For example, selecting the motion axis of a Pin connection

will create a rotational servo motor. Selecting the motion axis of a Slider connection will create a

translational servo motor. Selecting a Slot connection will create a servo motor that drives

motion along the direction of the slot.

Servo motors are displayed in the model as swirling cone shapes shown in this figure.

Creating Motion Axis Servo Motors

To create a motion axis servo motor, in the Type tab of the Servo Motor Definition dialog box,

select Motion Axis as the driven entity type.

You can click the Flip button to change the direction of the motor.

Motion Axis Motor Profiles

The Profile tab in the Servo Motor Definition box is where the motor's specifications are defined:

• Specification — The motor is controlled by Position, Velocity, or Acceleration.

• Initial Position — You can set the initial position of the motor (but not for Position

motors).

• Magnitude — You can define the magnitude of motion using one of nine different types

such as Constant and Ramp.

• Graph — You can graph the motor's position, velocity, and acceleration.

,reating lot !otors

A slot motor can be used to provide greater control of motion of a slot connection.

A slot motor:

• Acts along the tangent of a slot

connection.



Creating Slot Motors

A slot motor can be used to provide greater control of motion of a slot connection. It enables you

to place a motor that acts upon the tangent of a slot connection. You can use any of the available

motor profiles, and the slot motor can be used in both kinematic and dynamic analyses.

In the figure, a slot motor is used to “push” a model around a defined curve path.

Graphing the !agnitude of ervo !otors

Evaluate the magnitude of a motor by graphing its position, velocity, and acceleration.

Graph Magnitude of Motion:

• !osition

•

"elocity• Acceleration

Graph Tools:

• (xport

• !rint

• *oom and efit

• +ormat

Graph of Position, Velocity, and Acceleration

Graphing the Magnitude of Servo Motors — Theory

Graphing position, velocity, and acceleration of a motor enables you to evaluate the motor prior

to running an analysis. This enables you to be sure the specifications you have assigned to the

motor produce the desired results.

Creating a Servo Motor Graph

To create a graph of a servo motor, select the Profile tab in the Servo Motor Definition dialog

box of a selected motor. In the Graph area at the bottom of the dialog box, select any

combination of Position, Velocity, and Acceleration then click Graph Motor . This will

generate a graph of the selected magnitudes with respect to time. By default, the time period

graphed is 10 seconds.

The graph will open in a special Graphtool window.

The Graphtool Window

The Graphtool window provides a set of tools that help you view, share, and configure the

graph's display.

• Print Graph — Prints the graph.

• Toggle Grid Lines — Toggles on/off the grid display in the graph.

• Repaint — Repaints the graph.

• Zoom In — Zooms in on an area of the graph.

• Refit — Refits the graph into the window.

• Format Graph — Opens the Graph Window Options dialog box to format the

graph.

• File — In the File menu, you can export the graph as an Excel or text file.



#ssigning ,onstant !otion

Assign constant motion to a servo motor as a magnitude of position, velocity, or acceleration.

Constant Motion:

•

+unction, A

o !osition/

"elocity/ or

Acceleration

o A Constant

Coefficient

• Graph !osition/ "elocity/

and Acceleration

Graph of Constant Acceleration, with Resulting Position and Velocity

Assigning Constant Motion — Theory

You use a constant function to assign motion to a servo motor. You can specify the motion as a

magnitude of position, velocity, or acceleration.

Graphing the Magnitude of Motion

The Graph Motor tool at the bottom of the Servo Motor Definition dialog box, enables youto graph the position, velocity, and acceleration of your constant motion motor.

#ssigning Ramp !otion

Assign ramp motion to a servo motor as a magnitude of Position, Velocity, or Acceleration.

Ramp Motion:

•

+unction, A 0 12to !osition/

"elocity/ or

Acceleration

o A Constant

Coefficient

o 1 Slope

o t time

• Graph !osition/ "elocity/

and Acceleration

Graph of Ramp Acceleration, with Resulting Position and



Velocity

Assigning Ramp Motion — Theory

You use a ramp function to assign motion to a servo motor. You can specify the motion as a


Assign cosine motion to a servo motor as a magnitude of position, velocity, or acceleration.

Cosine Motion:

• Function: q = A*cos

(360 * t / T + B) + C

o q = Position,

Velocity, or

Acceleration

o A = Amplitude

o

B = Phase

o C = Offset

o T = Period

• Graph Position, Velocity,

and Acceleration

Graph of Cosine Acceleration, with Resulting Position andVelocity

Assigning Cosine Motion — Theory

You use a cosine function to assign motion to a servo motor. You can specify the motion as a

magnitude of position, velocity, or acceleration

#ssigning ,,# !otion

Assign SCCA motion to simulate a cam profile output.

SCCA Motion:

•

+unction, Sine ConstantCosine Acceleration

o Acceleration

o A )ncreasing

Acceleration

o 1 Constant

Acceleration

o 3 Amplitude

o T !eriod

• Graph Acceleration

Graph of SCCA Acceleration



Assigning SCCA Motion — Theory

You use a SCCA function to simulate a cam profile output. You can specify the motion only as a

magnitude of acceleration.

#ssigning ,ycloidal !otion

Assign cycloidal motion to a servo motor as a magnitude of position, velocity, or acceleration.

Cycloidal Motion:

• +unction, &2t4T # &2sin

562!i2t4T7462!i

o

!osition/ "elocity/ orAcceleration

o & Total ise

o T !eriod

• Graph !osition/ "elocity/ and

Acceleration

• (nables you to simulate a cam profile

output

Graph of Cycloidal Acceleration

Assigning Cycloidal Motion — Theory

You use a cycloidal function to assign motion to a servo motor. You can specify the motion as a


#ssigning Para$olic !otion

Assign parabolic motion to a servo motor as a magnitude of position, velocity, or acceleration.

Parabolic Motion:

•

+unction, A2t 0846

12t9

o !osition/

"elocity/ or

Acceleration

o A &inear

Coefficient

o 1 :uadratic

Coefficient

o t time

• Graph !osition/

"elocity/ andAcceleration

Graph of Parabolic Acceleration, with Resulting Position and

Velocity

Assigning Parabolic Motion — Theory

You use a parabolic function to assign motion to a servo motor. You can specify the motion as a




#ssigning Polynomial !otion

Assign polynomial motion to a servo motor as a magnitude of position, velocity, or acceleration.

Polynomial Motion:

•

+unction, A 0 12t 0 C2t9 0

%2t;

o !osition/ "elocity/

or Acceleration

o A Constant

Coefficient

o 1 &inear Coefficient

o C :uadratic

Coefficient

o % Cubic Coefficient

o t time

•

Graph !osition/ "elocity/ andAcceleration

Graph of Polynomial Acceleration, with Resulting Position

and Velocity

Assigning Polynomial Motion — Theory

You use a polynomial function to assign motion to a servo motor. You can specify the motion as

a magnitude of position, velocity, or acceleration.

#ssigning Ta$le !otion

Assign table motion to a servo motor as a magnitude of position, velocity, or acceleration.

Table Motion:

•

Create custom motor

profiles.

• ead data from text file.

Graph of Table Acceleration, with Resulting Position and

Velocity

Assigning Table Motion — Theory

You use a table function to assign custom motion profiles to a servo motor. You can createmotion profiles that cannot be defined by a function. You can also specify the motion as a




Evaluating #nalysis Results

!odule -verview

In this module, you learn how to evaluate analysis results. You generate analysis results and thencreate measures based on those results. You learn how to evaluate playback results and use the

animate dialog box. You also learn how to check for collisions between moving components.Finally, you learn how to create motion envelopes.

-$:ectives

After successfully completing this module, you will be able to:

• Generate measure results for analyses.

• Create analysis measure definitions.

• (valuate playbac' results.

• Use the Animate dialog box.

•

Chec' for collisions.• Create motion envelopes.

Generating !easure Results for #nalysis

You graph analysis measurements to help you understand and evaluate your mechanism.

Measure Results Dialog Box:

•

Graph Type• Measures

• esult Set

• Graph Measure

• &oad esult Set

• (xport esults

Graphed Maximum Magnitude

Generating Measure Results for Analysis — Theory

You graph and export the results of analysis measures to verify and evaluate the movement of

your mechanism.

The Measure Results Dialog Box

You open the Measure Results dialog box by clicking Analysis > Measures or by clicking

Measures from the Mechanism toolbar.

Measures and Results

The Measure Results dialog box provides three functions: to create measures, to graph the results

of selected measures, and to export the result of a measure to models as a parameter.



• Stop Animation !laybac' on Collision • Ring Message Bell when Colliding — With this option enabled, a warning bell sounds



Stop Animation !laybac' on Collision

Body Collides with Lift

Checking for Collisions — Theory

If you enable collision detection in Pro/ENGINEER, collisions between moving components willbe detected during dragging operations or during animation of the assembly's analysis results.You can stop movement when a collision is detected, or continue moving the component and get

a continuous collision view.

Collision Detection Settings

You can access the Collision Detection Settings dialog box by clicking Tools > Assembly

Settings > Collision Detections Settings or by clicking Collision Detection Settings in the

Playbacks dialog box. With these settings, you can specify whether your result set playback

includes collision detection, how much it will include, and how the playback will display it.

By default, Pro/ENGINEER does not check for collisions between moving components. Youmust enable and configure collision detection using the following general collision detection

settings:

• No Collision Detection — This is the default setting. When set, no collision detection is

performed and you are able to drag components smoothly, even if there is a collision.

• Global Collision Detection — Pro/ENGINEER will check for collisions in the entire

assembly and the collision will be identified in accordance with the optional selected

settings.

• Partial Collision Detection — Enables you to specify which components should be

checked for collision. This is especially useful in large assemblies where performancecan be an issue.

• Include Quilts — Select whether surface quilts will be included in the collision detectionprocess.

Use the following settings to determine how Pro/ENGINEER will notify you that a collision has

been detected:

g g g p , g

upon collision.

• Stop Animation Playback on Collision — With this option enabled, the playback stops

upon collision.

,reating !otion Envelopes

Motion envelopes are a faceted model created from the full motion of a mechanism.

Create Motion Envelope:

• :uality

• Selected Components

• Special 3andlings

• >utput +ormat

Motion Envelope from

Frame File:

• (xport +rame 5.fra7

+ile

• Save a Copy

Mechanism

Motion Envelope of Mechanism

proe mechanism notes

Documents