Rotating parts in assembly

[Lang]

I have a four-link system that is fully mated/contrained so each link moves correctly with each other and are bound by the supports. I can freely rotate either arm to see how the connecting link and the other arm move with respect to each other, which is nice. The issue I am having is I want to position the system at a specific setting by forcing one of the arms to a specified angle. In particular, I want the left arm to be completely vertical (90

 

[Mihail]

Mate the arm in the prefered position (using MATES). After that DELETE or SUPRESS mates. If you supress mates you are able to UNSUPRESS that mates and reposition quikly your assemblies. Is better to put this kind of mates in one folder because you can supress or unsupress all folder at once.


Hope that help you.

 

[ridein]

Use the planes of the part you want to control your mates. For example, if you want the part vertical, then use your part plane and use a oincident ,parallel or perpendicular mate it to your assembly plane.

 

[ttraser]

Under component properties, you might have to set the "Solve as" to Flexible. This will allow movement and maintain relations.


good luck,

 

[Lang]

Why is this program the worst I've ever had to use (perhaps aside from it's predecessor, Pro-Engineer)? It is quite literally a painful chore to work in. It hurts me so bad it makes me want to cut myself.


I'm here just trying to draw the most simple support: a rectangle with a round end and a concentric hole going through it. I first draw a rectangle. Then I draw a circle using perimeter and select two corners of the rectangle. Then I try the most basic of functions and MOVE the circle from the top quadrant point to the midpoint of the side of the rectangle I just constructed the circle from. Then I trim the rectangle corners and botttom part of the circle. I finish by deleting the line from the rectangle on the side I don't need anymore, and drawing a circle for the hole. Then I go to extrude the thing and it gives some stupid error about the sketch is not closed.


The problem that is going on is the program doesn't draw the circle correctly, or it trims improperly so if you zoom in REAL close you will see the endpoint of the arc and the point of the line don't match. What really boggles my mind is how can the program be so poorly designed that does do something so basic so terribly? I just can hardly believe this program is actually an engineering standard.


Ex: I draw a 2" x 1" rectangle. I fillet one corner to 0.5". I mirror the fillet about the centerline. The newly mirrored circle doesn't even line up properly with the other side of the rectangle! The line from the arc endpoint to the other side of the rectangle ended up being 0.964" How does that even pass as remotely acceptable? I can't wait until the day I graduate so I can buy a full copy of this program just to microwave it.


EDIT: Just look at this screenshot. I draw a circle from one corner of a rectangle to another corner using the perimeter option. This particular side is the 1" side. LOOK AT THE RADIUS OF THE CIRCLE. Even the relations show the ends of the circle are supposed to be coincident. It is nothing short of unacceptable. This program makes me so sick it is more worth getting a zero for this homework assignment than it is put up with this crap. My mental stability is at risk.

Edited by: Lang

 

[Mihail]

You are furious, but you have no reason ( yet ).


A poligonis a POLIGON because its lines has a COINCIDENT relations at the corners. The circle you sketch has not a COINCIDENT relation with the corners point of the rectangle. So, you have 2 separate sketches and... the error: SKETCH IS NOT CLOSED (bothe of them).


Draw your rounded rectangle in this way:


Sketch a rectangle.Declare the 2 lines of the rectangle (where the rectangle is rounded) as FOR CONSTRUCTION LINES.


Sketch a 3 points circle: First point in a corner of the rectangle, second point in the other corner and the third point outside of the rectangle. Now you can adjust your semicircle. The esast is to make the center COINCIDENT with dhe mid point of the side of rectangle but you can apply other relations ( for example tangent or what you want).


Repeat this stepsfor the other side.


NOW you have a CLOSED sketch


Dimension your sketch and EXIT for extrude.


Good luk ! Sorry for my english.

 

[michael3130]

Woo....major rant.


But a bad workman always blames his tools.


Lang, it's hard to tell from your one sketch but since all the lines are blue, it would appear that you haven't constrained things properly. SW is an excellent engineering package and since this is a very basic thing you are trying to achieve, I don't think SW is to blame.


Michael

 

[ttraser]

Woo....major rant.


But a bad workman always blames his tools.


Lang, it's hard to tell from your one sketch but since all the lines are blue, it would appear that you haven't constrained things properly. SW is an excellent engineering package and since this is a very basic thing you are trying to achieve, I don't think SW is to blame.


Michael





I love the workman part... You hit it on the head there Michael.


Bring in the cheese and crackers for this guys WINE>>>>>>>


lmao.





GoodLuck,

 

[mjcole_ptc]

Or Use
Trim Entities > Show all options if prompted then use the
Power Trim option

This option is like the Pro/E one which allows you to hold down the left button and drag a line through the entities you want to trim. Did you ever try creating a similar sketch in Pro/E and get the same error message.

The reason the coincident consraint isn't working in your pic is you do not have a tangent constraint set.

Michael

 

[nucu]

Hi Lang

First of all in SW those values in prop. manager are not fixed values. Are informative. If you want fixed values add dimensions.
A simple method to sketch your rounded rectangle. Draw a hor lin. After you click end point of line press A key. It start an arc that is tg on the first line.Finish the arc using the witness lines.After you click the end point of the arc the sketch is continued with a line. Continue your sketch until you close it. Insert dimensions.

Nucu