How to Master the FK/IK Switch in Maya: Advanced Animation Techniques

Hey, guys, it's Monica at Academic Phenix Plus. And welcome or welcome back to a rigging tutorial. And in this one it's about The powerful but confusing FK and IK switch. I'm going to do is explain what it does and then show you how to make it. It's multiple steps, so let's go ahead and get started. If you are new to this channel, I post videos on a weekly basis. Software includes Maya, ZBrush, Substance Painter and more. So if that is your sort of thing. please consider subscribing. So bring ou

t that creativity, open up that software and let's go ahead and get started in creating the FK IK switch for rigging. All right, so what are we trying to do? We want our arm to do two things. We want it to do FK which is Forward Kinematics, which is like waving your arm. Right. So I have these controllers. And if you want to like wave your arm like hi there, how's it going? You can so you can get some really nice, overlapping animation like walk cycles. Any type of animation that requires secon

dary animation. However, we also want and I'm going to hit this Ctrl H and bring up the IK. We also want IK and I also have a controller to go with it. So let me bring this up. And the idea is that we also want the power of IK. So IK is really great for sticking. So here you are. You have your hand or your arm on the waist. And then if I move this one the arm let me see a better angle. The arm is sticky right. Which is great for things like let's say you are trying to push something open and you

want your hands to get stuck on the door so you don't have to counter animate with an FK. You can do it with an IK. Or let's say your character's on a swing and that you want them to hold on onto the chain. Then you don't need to counter animates. You can stick the IK onto the chain and it will stick. So we want both. We want the power to be able to do FK and IK. So how do you do that. Well, we're going to need three chains. We're going to need the IK chain which is here. And I change it to yel

low for visual purposes. So IK is in yellow, which is inverse kinematics. FK is in red, which is forward kinematics. And we're also going to need a third chain. This third chain is the one that's going to be binded onto your character's skin. We have three chains. We have the IK, we have the FK, and then we also have the one that's going to be binded. And of course it's the one that also has the hands. The next step is how do we influence just what the FK and the IK. That's why constraints come

in. So I'm going to open up my shoulders and elbows and wrists. And I'm going to open up the FK as well. And I'm also going to open up the IK. The magic is constraints. So we're going to do is first select the IK shoulder, then the FK shoulder, and then the shoulder that's going to be influenced. So we're going to go to constraint. We're going to go to parent and then go to the options. You want to make sure maintain offset is on. And then click add. And what we're going to get is the shoulder j

oint has a constraint. And you'll also see that in the inputs or the shape node. You're going to notice that we have an FK and IK options. And right now they're one one. So what that means is that this is being influenced by 50% of The IK and then the FK. So let me see if I can demonstrate. I'm going to select my OK and I'm just going to move it aside. And you can see that main joint, the one with the hand that's going to be influence, is being affected by the IK and also by the FK. And that's w

hy it's in the middle at 50%. I select the constraint which you can find here, which looks like a little chain, and change the IK shoulder to zero, you're going to notice that the IK no longer influences it, and it's permanently being driven by the FK. FK. Now you'll notice if I grab this one, it's not being influenced because I haven't done the constraint to that one. And going back to this one, if I change this back to one, the IK and then change this to zero, you'll notice that it follows the

IK, right? Because I'm basically saying that IK is 100% being influence and FK is at zero. So how do we tell Maya to switch from one to the other? I'm going to undo this so I can put them all back into place. That's why we need what's called an FK IK switch. I already created one and it literally acts like an FK and IK switch. And this is going to be a mix of all the video tutorials from rigging, which is we're going to be using Set Driven Keys to drive this. So to create a set driven key, we'r

e going to go under animation. We're going to go to Set Driven. Set dot dot. Click! And our driver is going to be the FK IK. If you guys need a video on explaining what the driver and a driven is, I have a video tutorial on the fingers and I explained it all. But basically this is the one that's going to lead it. And the driven is what's going to be dragged around. I have my IK FK switch and you're going to notice that I don't have any options here to do the switch. So I need to add an attribute

. So let me close this. Let's go to Edit Add Attributes. And up here I'm going to say FK. And you can put an IK a space or an underscore. FK IK Switch. I want it to go from 0 to 1 and then click okay. So it's right here Now I can do it. Let's go to Key, Set Driven Key, Set... Again I'm going to do the driver. I'm going to select the FK IK switch. And then I get to tell it okay what are we driving. We're going to be driving the constraint. This is going to be the driven. And I'm going to set like

these two, the FK and the IK Constraints. Back to the switch, selecting this, right now my switch is at zero. I'm going to say that's FK. So I'm going to go back to my constraint. Select these two and make sure that IK is turned off. So that means that FK is the lead. And then click key. Then I'm going to go back to my switch and change this into a one. I'm going to go back to the constrain and do the opposite. I want IK to be the lead and FK to be zero. Then click key right. So what's going to

happen is that I'm going to grab this again. Last time. Again there's no influence in the in the elbow. So that's why it's being influenced like that. But you can see that wherever the shoulder goes so does the the lead joint. Now the for whatever reason my joints on our lining. And that's something that happened when I was doing the IK. But hopefully you guys get the idea of what's going on. You should have your joints be aligned exactly. I'm missing a, elbow control for the IK, so that's prob

ably part of the issue. But anyway, the it's working. What's cool about the switch though, which is the magic about it, is that if I change this to zero, the leading arm will pop back into the FK. With just using the switch, I can go back and forth really quickly. But what's really magical about this switch is that I can use what's called blending. So because I have a 0 to 1 value, I'm going to middle mouse and drag slowly. You can see that I can actually create what's called a blend. That means

that I can animate from the FK to the IK, basically seamlessly. So if I have an animation, what the FK is doing its thing, and then I need to switch to IK, I can either snap it really fast with a keyframe, or I can actually do a blend, which is magical. Magical. All right, I'm gonna change this back to zero and I'm going to change this back to zero as well. So everything's back aligned ish. And I'm going to do it again, but this time I'm going to do it to the elbow. So same story I'm going to g

rab IK first, then I'm going to grab the FK second. And then I'm going to grab the left elbow joint. Then I am going to go to. Constraint parent. Then I've got my FK IK switch here. It's a zero. I am going to select my new constraint which is the elbow. That's going to be driven. And I'm going to select these two again. Right now my switch is at zero which is fk. So I'm going to go ahead and remove the IK. No influence on IK and then click key. Going to go back to my switch. I am changing this t

o one which is the IK. Going to go back into my elbow and switch it. I want 100% influence on IK and zero influence on FK. Then click Key. So now my switch is going to go back to back and forth. So again I'm going to select this. I'm going to actually bend it. And you can see that the IK is actually moving and the elbow is going with it or the forearm. Right. And I can grab this one and maybe make some sort of again I'm going to move this and I can go to my switch and I can go to 0 to 1. And you

can see that my arm actually goes between 0 or 1. And it fits really well. Loop. And that's what makes it really awesome, really magical. All right. Let me, change everything back to zero because I rotated and translated. So let me get my rotations back here, and then this can go back as well. And now I have an FK IK switch. However, this is a little bit confusing. The confusing part is that, I see all the controllers, all at once and I want those to not exist. If I want the FK to be active, th

en I want the IK to disappear. So we can do that as well. We're going to do the FK IK switch for invisibility. So going back to my switch. Again, I'm going to make sure I'm at zero because I'm starting with FK and I am going to select all of my FKs. So just going to go through here, you can use the outliner or you can select it in your scene. And this is going to be the driven. So I'm going to select these guys. And here's my visibility. And right now my switch is in FK. That means FK should be

100%. That means I should be able to see all of the FK. So I'm going to go ahead and Key it. However, when my switch is in IK, which is when I hit one, I want these guys disappear. So I'm going to go to zero and then click key. So now when I go to FK IK switch, if I go to zero they pop up. Pink. I'm going to do the same thing for IK. So again my switches here, I'm in FK mode. I want IK to disappear. So I'm going to select my controller and then to do the driver going to grab the visibility, turn

it off because again I'm an FK mode. Key. Now with the switch I'm going to change this to one. I'm going to go back to my IK controller and turn this on key. And there we go. We now have an FK IK control. I'm going to close this because we don't need anymore. But we can select this. You can change it to zero. You'll see that these pop. It's if I move this it's going to act, it's going to act like it's an FK, which is great. We then I'm going to grab my switch. I'm going to change it to one. Not

ice that it's now an IK. The FK controllers have disappear. And this has been influence 100% by that. And that is how you can create an FK IK switch. So hopefully you learned a thing or two. If you did, please like and subscribe. That is your message to me letting me know that you like this content and you want to see more. Please leave a comment. What did you think about this, tutorial? Did you find it interesting? I think it's actually really cool that you can easily switch from. Let me get a

better angle here. You can easily switch from FK IK and have a blend. Your goal as a Rigger is to make sure that you create tools that are really helpful for our animators. Also, take a look at Academic Phoenix Plus dot Com. There you can find free resources like 3D models, reference images, ebooks and so much more. So take a look at Academic Phoenix Plus dot com for more content just for you. And again, thank you so much for watching. I really appreciate it. Keep creating and I look forward to

seeing your characters. come to life using an FK and IK Switch.