Joint Definition - Friction

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Joint Definition - Friction
Joint Friction is determined based on the parts
connected by the joint. By default materials
from SW are used and a default of dry steel for
friction and contact properties. The user can
override this at any time by selecting other
materials from the database or by using custom
values for friction and Joint dimensions.
Joint dimensions relate to the dimensions of the
surfaces in contact for the joint to determine
frictional components from every load direction.
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Joint Definition - FEA
Select the features on each part that the joint
loads will be distributed over when results are
exported to FEA Multiple faces can be selects
for each part. Loads are evenly distributed over
features For joints generated from assembly
constraints, the loads can be automatically
mapped to the features used to define the
constraints. This option appears when you export
loads to FEA.
Only features on the current part will be
recognized when selecting faces Features can be
removed by clicking on them in the dialog window
and then pressing the delete key
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Contact - Point-Curve
Constrains a point on one part to follow a
profile on another part. The point is still free
to rotate in any direction Curve can be open or
closed Picking on a surface when defining a
curve selects all the outer edges of the face
automatically Points per Edge Curve controls
accuracy of spline fit to profile defined. The
number refers to the number of points the spline
must pass through on each edge portion. Total
number of points permitted per curve is 800 If
not in an assembled position, solver will move
the point to the nearest position where it lies
on the curve
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Contact - Curve-Curve (Continuous)
Curves can be open or closed Curves can be 3-D,
but must only touch at one point Solver will
terminate if the contact point reaches the end of
an open curve Picking on a surface when defining
a curve selects all the outer edges of the face
automatically Points per Edge Curve controls
accuracy of spline fit to profile defined. The
number refers to the number of points the spline
must pass through on each edge portion. Total
number of points permitted per curve is
unlimited If not in an assembled position,
solver will move the parts to make the curves
contact at the nearest position
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Contact - Curve-Curve (Intermittent)
Curves can be open or closed Curves do not
necessarily stay in contact A contact parameters
tab allows for material specifications for
contact definition Curves must be 2-D and
parallel at all times No limit on the number of
points Curve Flip used so that arrow MUST point
into the solid from the edge of the curve (ie it
defines the side of the curve that the solid is
on)
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Contact - Curve-Curve (Intermittent)
Can uncheck or check intermittent contact here
also Output frame option enforces a result frame
when contact/collision occurs independent of the
number of frames specified in the simulation
parameters (but only for that curve-curve
definition ) Contact properties are modified
clicking on this button
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Contact - Curve-Curve (Intermittent)
Default materials for parts appears, but can be
overridden. Collision parameters can be
customized for specific contact definition.
Coefficient of Restitution offers a simple
interface to contact parameters. Friction takes
into account the static and kinematic friction
transition.
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Couplers
Allows the proportional movement of one joint
with respect to another. Can link Rotational -
Rotational Rotational - Translational Translatio
nal - Translational Available for combinations
of Revolute, Cylindrical, and Translational
joints One joint can be linked to multiple
joints provided they do not conflict with motion
generators or other couplers Couplers are
primarily used for representing gears without
taking into account losses
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Linear Springs
Same format as Action/Reaction Force Only
supports Linear Springs Length defaults to be
initial distance between attachment
points Design toggle option allows the user to
specify any length at which the specified force
exists in the spring
If Force is set to zero, length indicated is the
free length
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Linear Dampers
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Torsional Springs
Angle is equivalent to length for linear
spring Torque value indicates amount of pre-load
in the spring at the specified angle If Torque
is zero, Angle specified is the free angle
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Torsional Dampers
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Joint Definition - Motion with Arbitrary Function
Use a or - to combine multiple
functions Start on a new line by using the
Ctrl-Enter command Use any array of
mathematical functions to define expression
(refer to following slides) Refer to help for
full function definitions Expression units are
in radians for rotational motion and assembly
length units for translation (also depends on
time units)
This icon gives information on the points located
on the separate parts attached by the joints.
This is an interim step to providing an advanced
graphical function builder (see next slide)
Predefined functions can be used by clicking on
the Fx button. If text is highlighted in the
expression window, it will be replaced by the
function selected using the Fx button
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Joint Definition - Motion with Arbitrary Function
Use this button to validate expression. If
errors are detected a dialog will appear
indicated location of error. Correct the error
and click on the Tick button to re-check
expression
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Joint Definition - Supported Functions
Function Name Summary Definition ABS Absolute
value of (a) ACOS Arc cosine of
(a) AINT Nearest integer whose magnitude is not
larger than (a) ANINT Nearest whole number to
(a) ASIN Arc sine of (a) ATAN Arc tangent of
(a) ATAN2 Arc tangent of (a1, a2) COS Cosine
of (a) COSH Hyperbolic cosine of
(a) DIM Positive difference of a1 and
a2 EXP e raised to the power of
(a) LOG Natural logarithm of (a) LOG10 Log to
base 10 of (a) MAX Maximum of a1 and
a2 MIN Minimum of a1 and a2 MOD Remainder
when a1 is divided by a2 SIGN Transfer sign of
a2 to magnitude of a1 SIN Sine of
(a) SINH Hyperbolic sine of (a) SQRT Square
root of a1 TAN Tangent of (a) TANH Hyperbolic
tangent of (a) IF Defines a function
expression
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Joint Definition - Supported Functions
Function Name Summary Definition CHEBY Evaluates
a Chebyshev polynomial FORCOS Evaluates a
Fourier Cosine series FORSIN Evaluates a
Fourier Sine series POLY Evaluates a standard
polynomial at a user specified value
x SHF Evaluates a simple harmonic
function STEP Approximates the Heaviside step
function with a cubic polynomial STEP5 Approxima
tes the Heaviside step function with a quintic
polynomial
OPERATORS Symbol Operation Exponentiation / D
ivision Multiplication
EXPRESSIONS AND FUNCTIONS Function Name Summary
Definition DTOR Degrees to radians conversion
factor PI Ratio of circumference to diameter of
a circle RTOD Radians to degrees conversion
factor TIME Current simulation time
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Joint Definition - Result Dependant Functions
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Joint Definition - Result Dependant Functions
Motion Generators, Forces, and Moments allow the
use of result dependant functions as part of
their function specification. These can be
entered for Joint motions, Forces, or
Moments. Marker IDs Many of the ADAMS functions
use Marker IDs as parameters to the function. To
determine the Entity ID or the ID of markers
attached to an entity, the marker icon listed on
the function dialog will bring up a list of each
motion entity and then the marker ids underneath
those entities. All Dynamic Designer Motion
entities display some information under the title
ADAMS Solver Data. This includes the Entity and
the ID of the markers attached to the entity. In
the image to the left, the Distance2 Constraint
has two markers with IDs of 27 and 28 on parts 1
and 4 respectively. If I were measuring angular
velocity of Part 1 with respect to Part4, I would
use the WZ(I,J) functions where I would specify
WZ(27,28) to measure the relative rotational
velocity of Marker 27 with respect to Marker 28.
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions
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Joint Definition - Supported Result Dependant
Functions