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NX 8.5 Sequence Simulation

Creator
Creator

I am a student and I am new to NX 8.5. I need to use a timed sequence for a simulation of a production floor. I cannot seem to find any resource material related to this. Can someone please provide me some guidance on how to do this?

11 REPLIES

Re: NX 8.5 Sequence Simulation

Siemens Creator Siemens Creator
Siemens Creator

Time sequencing in NX:  NX Motion Simulation with Solution type Articulation or Spreadsheet Run; Normal Run solution with  Driver Functions like IF or STEP. There is also Mechatronics Concept Designer with Sequence Editor. MCD is suitable for automation engineer type of work.

In case, there are also dedicated solutions in Manufacturing (Tecnomatix): Process Simulate, Plant Simulation.

Gilles Dubourg
Product Manager – Simcenter 3D Motion
Product Lifecycle Management
Siemens Industry Software SAS
gilles.dubourg@siemens.com
www.siemens.com/plm

Re: NX 8.5 Sequence Simulation

Creator
Creator

Thank You for the information and quick reply. I have already modeled a production floor with two conveyor belts and a pick & place robot arm. I need to simulate this process where a toy car comes on one conveyor belt and then the robot arm picks and places it on a plastic casing which comes on the other conveyor belt.

 

Therefore, I needed to know how to simulate this in a sequential motion. I will check the options you told.

Re: NX 8.5 Sequence Simulation

Creator
Creator

I am having trouble finding study material related to this, it would be great if someone could point me in the right direction and/or provide with some descriptive information on this matter.

Thank You!

Re: NX 8.5 Sequence Simulation

Siemens Creator Siemens Creator
Siemens Creator

I suggest looking in the NX documentation. Mechatronics Concept Designer/Quick Start Guide.

For more accuracy, if needed, NX Motion Simulation, for starting, there is a simple video to wacth http://www.youtube.com/watch?v=bDf5JMwakP4

Then look in Function Manager as drives (Motion-Functions), IF function, use Markers and sensors.

Gilles Dubourg
Product Manager – Simcenter 3D Motion
Product Lifecycle Management
Siemens Industry Software SAS
gilles.dubourg@siemens.com
www.siemens.com/plm

Re: NX 8.5 Sequence Simulation

Community Admin Community Admin
Community Admin

@Student777 -

 

I suggest you also look at downloading our Tecnomatix Plant Simulation Software (free download) as suggested by @Gilles . We have a forum dedicated to using Plant Simulation where @RalfTobel @abhidastidar can help with questions. 

 

Thanks!
Susan

 

If you find my post helpful, and it answers your question, please mark it as an "Accepted Solution"

Re: NX 8.5 Sequence Simulation

Creator
Creator

Hi,

 

Thanks for the response and the assistance. I\ve been working with NX motion simulation for a couple of days now, and Ive managed to make a few small simulations.

 

I've managed to implement drivers where i need them, and I figured out how to place the IF and STEP functions into them.

 

Im having trouble understanding how they should be defined, and how to correlate them with sensors I define in the simulation.

 

Cant seem to find any step by step example of a sequential simulation in the documentation on NX...

 

I apologize for bieng rather unfamiliar, if you could help I would greatly appreciate it

 

 

Re: NX 8.5 Sequence Simulation

Siemens Creator Siemens Creator
Siemens Creator
Spoiler
 

 

See below README information with function formulas that should help for sequencing with NX Motion function Manager. It's coming attached with a sample I can provide, saved in NX9. I can easily redo in NX8.5.

Kind regards,

Gilles

 

Links
-----
displacement_object = Link that moves horizontally
Door = link that is the door that will open and close
baseline_dummy = is a fixed link so a sensor or a marker can be fixed at a relative location.

Markers and Sensors
-------------------
A001 = marker attached to link displacement_object
A002 = marker attached to link Door
A003 = marker attached to link baseline_dummy

se001 = X(abs) displacement sensor that is attached to Marker A001 which is attached to
        link displacement_object.
se002 = Z(rel) displacment sensor that is attached to Markers A002(Door) and A003(baseline_dummy)
        When this is near zero, the door should stop Closing.

---------------------
MOTION: kinematic_if:
---------------------

Functions
------------
door_velocity =
if(Se001-6:0.0,vel_up,if(Se001-8:vel_up,0.0,if(Se001-10.75:0.0,vel_down,if(Se002-0.125:0.0,0.0,1.0*vel_down))))

You can also set up the function as follows, in the Function Manager dialog.  Each if is part of the
nested if statements and NX automatically will combine them, based on the parentheses

door_velocity =
if(Se001-6:0.0,vel_up,
if(Se001-8:vel_up,0.0,
if(Se001-10.75:0.0,vel_down,
if(Se002-0.125:0.0,0.0,1.0*vel_down))))


vel_up = .25 in/sec
vel_down = -.25 in/sec

The nested IF statements are needed to control when the door opens and closes. 

1. When the displacement of the se001 is between 0.0 and 6.0in. then the velocity of link Door is 0.0
2. if Se001-6.0 is 0.0, then the door move at velocity in vel_up.
3. if Se001-6.0 > 0.0, then a nested IF controls the velocity of the door.  When
   the displacment_object start through the door (ie. Se001-8.0), then the door stops moving.
   When displacement_object is beyond the door (ie. Se001-10.75) then the door moved down and
   eventually stops when Sensor Se002 is near zero.

-----------------------
MOTION: kinematic_step:
-----------------------

In some cases, IF statement could be too brutal for the solver to adjust and converge.
Recommendation is then using STEP with a small lag, BTW, this is much closer to the physical behavior.
STEP could be used when independant variable is not Time but a sensor (event).
The sample uses a displacement function.
You can change the speed of the blue block (displacement_object) via its velocity on J001.
The door should still open and close. For example, try 0.2; 0.3, 0.5 in/s.

door_displacement=
STEP(Se001+.01,0,0,.01,1.01)
* STEP(Se001-2.5,0,1,.01,0)
*STEP(TIME,0,0,.01,1)

The STEP function in TIME was added to ensure 0 displacement of the door for the very first step.

-----------------------
MOTION: kinematic_best:
-----------------------

The door is driven in velocity which is more physical.
The blue block velocity is an NX expression (velocity), the step function is event dependant
The step variation profile remains the same whatever is the blue block velocity: delta=x/velocity
So it starts depending on the sensor information with always the same time profile to reach the .25 in/s
The solution time is also a parameter dependant on the blue box velocity. Such as the number of steps is
sufficient for the time of interest.
In that motion simulation, you can try velocity of 0.25 up to 0.4 in/s
CTRL/E to change the velocity. When over 0.4 in/s, then the actuator speed should be increased as well.

Gilles Dubourg
Product Manager – Simcenter 3D Motion
Product Lifecycle Management
Siemens Industry Software SAS
gilles.dubourg@siemens.com
www.siemens.com/plm

Re: NX 8.5 Sequence Simulation

Creator
Creator

Thank you for the help and the coding. It is very helpful. I managed to run a STEP function without any errors, I am working on the rest of it too. I will inquire if there any more issues.

 

Thank you!

Re: NX 8.5 Sequence Simulation

Creator
Creator

Hi, I have been working with the motion simulation and progressed a lot through my project. Now I am trying to simulate a conveyor belt, on which a part moves, and is picked up by a robot and placed on another conveyor.

 

I am unable to make the conveyor work since the simulation reads it as a rigid link and hence cannot be rolled around. It is not necessary to show the conveyor work. All I want to show is that the part is moving on top of the conveyor belt and be picked and placed onto another belt.

 

I am unable to figure out how to insert multiple drivers onto the car such that it moves as a slider first, then is a free link under the influence of the robot, and again slides over the conveyor.

 

Could you please guide me as to how i could approach this senario?