How to linear trajectory for robotic arm?

[Anonymous]

PLease help! When the animation starts the end point makes arc trajectory. How can I make it to do a linear trajectory? (Mechanical arm is interconnected and all joints function and hold together

[ads_royje]

Hi,

by default in Max the position controllers are bezier float with smooth tangents.

You can achieve this in 2 ways; Via a Controller or you can set it per keys.

Per Controller :

You can change them to use linear float controllers for your positions.

To change controllers,

Select your object and go Control Panel > Motion Panel > Parameters

Select the Controller you want to change

Press the Square button above and choose the 'Linear Float' controller.

This will set that controller to Linear for the whole animation.

Per Keys :

Or you can also just change the keys for a linear interpolation if you wish to have linear and smooth mixed keys.

Open the Track View ( Main menu > Graph Editors > Track View - graph editor)

Select your object and select the function curves you want

Select the Keys you'd like to be Linear

In the UI, set them to Linear (in the red box below)

This method allows you to have a mix of linear and other interpolations per keys.

For instance, in this screenshot below the x (red) is set to linear keys, where the z (blue) is the default bezier smooth tangent.

Hope that can help! 🙂

[Anonymous]

Thank you, but it still did not help. Line in Curve editor is not curved but trajectory of motion is curved.

[Anonymous · Accepted solution]

Please, Can you do online support via TeamViewer?

[ads_royje]

Unfortunately not 😞 sorry.

I understand that you may not want to share your file, that is ok, you don't have to.

I'm asking because that is the fastest way to understand what is going on in the animation.

A screenshot with hierarchy displayed (scene explorer) and related animation can help trouble shoot what is happening.

If there are rotations in a parent, an arc end result can be expected as you probably know!

[Anonymous]

OK, but I can not add a picture, I do not know why

[ads_royje]

hum... that is strange,

you should be able to insert or do an attachment 

[Anonymous]

I do not view this menu. Some Adobe problem?

[Anonymous]

I have a model - automobile industry robot (in 3ds max 2016). http://www.designall.sk/.../2016/07/rh-12fh8535_asm.rar I need to adjust the movement of his arms (in 3ds max 2016). Set motion, for example like this gif http://www.duber.cz/camtasia/ArmSwitcher/ArmSwitcher.gif Thnx Youray

[ads_royje]

unfortunately, the link to the rar archive is truncated ...

it has a " /.../ " into it 😕 

can't get to it.

[Anonymous]

 Please see picture

[ads_royje]

Ha! I see!

That is the expected behavior for an IK Chain, it is called the "preferred angle".

If it could fold both sides, it would cause the system not to know which side it should fold and would get to flicker from a side to another.

So depending of your intent in animation, you may have to build this using different solution.

[Anonymous]

Thank you, but what other solution is correct?

[ads_royje]

That would depend on your animation intent, if it is to have the bones to rotate from the left to right, then it would be to use just regular rotations on the bones, no Ik.

For mechanical motions, I'd use rotations, they represent very well how they move.

You could try Spline Ik too, this one would allow your to fold the bones on both sides, being controller by the spline it self.

But that may not give the exact results you'd be looking for.

Bones are driven by the spline, and the spline is controlled by helpers. You can give it a try and see if you can control as you'd like it.

[Anonymous]

I found a new ,,way,,. It's great, but when you start the animation can not move linearly end point. Please see this video
http://www.designall.sk/wp-content/uploads/2016/07/new-way.mp4

[Anonymous]

,,end point,, of bones

[ads_royje]

indeed, the ik is 'interactive'

meaning that is manipulation is an ik, but there is no ik solving in the animation, so what is actually keyed are rotations on the bones.

[Anonymous]

ok please write me how you know that I could do?

[ads_royje]

I'd like too, but would need to understand what is your animation intent.

Any example videos that shows what you're trying to achieve, any reference material ?

[Anonymous]