BIK: Full Body IK Solver

[darkZ]

@Aumaan Anubis;454952

1. Can we define how far up the chain the IK effects, and how strong the effect is for each bone in the chain? (In your walking example, I would like to have the character lean their upper body forward when climbing a steep slope, and lean backwards when walking down it) And have the pelvis partially shift in height as the knees raise?

• 1. Is there a way to (or plans to) place effectors with precision? (enter exact co-ordinance, world space, or relative to affected bone, or snap to bone-root or bone-tail)
• 1. For the collision support example: will there be a way to interpolate to the new foot position? (to simulate the character lifting their foot up)

1. You should be currently able to define how much the root is effected by the end effectors especially when the effectors get pulled away. This control is something I am refining a bit more for an upcoming update. Leaning backward or forward requires balance control, which I also intend to implement in a future update but not in the next upcoming update.

2. If you look at some of the quick start videos (https://youtu.be/qmQZ0zCwQAA), the effectors can be directly controlled in world space by inputing the coordinates if so desired. There is also plan to parent the effectors so that local control would be easily possible. This should be released relatively soon.

3. There is definitely a plan to implement interpolation, however even better results can be obtained via the smart procedural footstepping for such scenarios if this is what you meant (https://youtu.be/DZU5iP5u8U8) as this allows for a full animation to be used in case the feet are to be planted at a location much further away than their current location as interpolation might not produce desirable results.

[darkZ]

@nkey;455062

Have an idea for you (and feature request).

Currently it is not possible to use root motion animations in MP game in UE4. And many people uses in-place animations anyway. Because of not perfectly matching in blendscape + replication issues (player position replicated to not exact location) player see some kind of floating character. Not much, but floating. It is possible to fix using IK (sync foot floating/position with actual characted mesh movement).

It is definitely possible to fix the floating on the client side via IK, however currently that’s something I haven’t really explored. But it is probably a nice to-do for some future work. Thanks for the suggestion !

[darkZ]

@Rhynedahll;455124

Will this work with terrain or only with objects?

This should definitely work with terrains as well any objects which can handle collisions.

[starfighterdude (Bruno De Araujo)]

This is awesome, good job

[n00854180t]

@ - I noticed that the “Parent Socket” drop down functionality no longer works as it does with a skeletal mesh, for attaching subcomponents to a particular bone. I use this a lot, is it something that can be easily fixed?

Thanks man

---

For those that have the same problem, you can work around it by attaching your component to the appropriate bone or socket in the construction script, passing in the BIK component -> Get Skeletal Mesh as the parent.

[darkZ]

@brunogruber;457875

This is awesome, good job

Thanks man !

[darkZ]

@n00854180t;458193

@ - I noticed that the “Parent Socket” drop down functionality no longer works as it does with a skeletal mesh, for attaching subcomponents to a particular bone. I use this a lot, is it something that can be easily fixed?

Thanks man

---

For those that have the same problem, you can work around it by attaching your component to the appropriate bone or socket in the construction script, passing in the BIK component -> Get Skeletal Mesh as the parent.

Thanks for the bug report and the workaround, appreciate it ! I will see what’s going on and work on a fix as soon as I finish working on the current solver implementation which should resolve a lot of singularity issues which can occur while solving for various limbs. More soon !

[phantom530]

How easy is this system to implement into my project?

[anonymous_user_27077513]

Where i can get this plugin ???

[mzprx]

Hi, this looks like a really great plugin made with love.

1. What are the pros and cons in comparison to Ikinema UE4 plugin ?
2. What are the limits for indie license ?
3. If I get it right, this is closed source plugin. UE4 is changing very fast, so what happens if I buy this plugin and will stop developing it and adding support for newer versions ?

[darkZ]

@phantom530;460264

How easy is this system to implement into my project?

This should be decently easy to setup in any project. Can you describe a bit more of what you are wanting to achieve with your particular project ?

[darkZ]

@demonith88;460330

Where i can get this plugin ???

Currently this plugin is for purchase only. Small indie team license is USD 99.99, but please contact [EMAIL=“”] for further details.

[darkZ]

I am making good progress with collisions for end effectors with ground/terrain and world objects.
You can set up different trace response channels to respond to the effectors independently.

Also, shown here is a new efficient limb solver combined with the full body solver. This should scale to quite a few characters being controlled via IK.

These along with the component version of the effector class is being readied for the next upcoming update. More soon !

Out of the box physical interaction with objects using BIK plugin for UE4

[Aumaan_Anubis]

Incredible work!

@;466148

You can set up different trace response channels to respond to the effectors independently.

Could you elaborate on this? What are some things that can be done with this (I guess I’m asking: what’s the expected use case for this?)

[darkZ]

@Aumaan Anubis;466153

Incredible work!

Could you elaborate on this? What are some things that can be done with this (I guess I’m asking: what’s the expected use case for this?)

Thank you !

Imagine you only want the feet to collide with the ground and the hands with certain kind of objects. You can assign, let’s say, a trace channel “HandCollision” to those objects as blocking. And then in the blueprint for the IK you would set the corresponding collision response for the hand effectors to “HandCollision”. And similarly, you could create a different collision channel for feet effectors, let’s say, “Terrain”, which you could assign to all the ground objects for the feet to interact with.

One use case for this is VR controlled hands. Here, you don’t want your hands to intersect world geometries even though your motion controllers want to move the hand in certain direction.
Another use case would be when your animation is trying to play some reaching, opening door, lifting object or pointing motion but there’s something in the world blocking this kind of motion. All of this is very useful in case you have dynamic world and dynamic interactions.

[darkZ]

@mzprx;460708

Hi, this looks like a really great plugin made with love.

1. What are the pros and cons in comparison to Ikinema UE4 plugin ?
2. What are the limits for indie license ?
3. If I get it right, this is closed source plugin. UE4 is changing very fast, so what happens if I buy this plugin and will stop developing it and adding support for newer versions ?

Hello mzprx,

Thank you for your kind words.

1. There is a procedural stepping work which will be included with a future update. Imagine having Sims like functionality for all your player and NPCs in your game where you just direct the character to perform a task. Here’s a video I have previously posted : https://youtu.be/DZU5iP5u8U8 So, this is going to be much more advanced than just IK in the future. By purchasing now you can be a part of that story by contributing your inputs and shaping the direction the plugin takes.
2. Indie license is limited to small teams with annual revenue of less than 80,000 USD.
3. If development ever ceases, which I doubt it will, but if it does, I will consider releasing source code at that point so that existing customers can continue to use the plugin with newer builds of UE4. That being said, development is not stopping anytime in the forseeable future.

[darkZ]

@n00854180t;458193

@ - I noticed that the “Parent Socket” drop down functionality no longer works as it does with a skeletal mesh, for attaching subcomponents to a particular bone. I use this a lot, is it something that can be easily fixed?

Thanks man

---

For those that have the same problem, you can work around it by attaching your component to the appropriate bone or socket in the construction script, passing in the BIK component -> Get Skeletal Mesh as the parent.

Hey n00854180t*,

*I am trying to investigate this issue. Would it be possible for you to record a quick video or share some screenshots to elaborate a bit more ? You can send those over to my email. Thanks for your help !

[n00854180t]

@;466170

Hey n00854180t*,

*I am trying to investigate this issue. Would it be possible for you to record a quick video or share some screenshots to elaborate a bit more ? You can send those over to my email. Thanks for your help !

Sure! I’ll get some screens/video later today after work.

In the mean time, I can try to describe the issue a bit more:

If you set up BIK to use the BIK component with everything included (the one that replaces the SkeletalMesh), and you drag another component (e.g., a static mesh) to parent it to the BIK component, and then select the child component, and look at the “Parent Socket” selector, clicking it just doesn’t do anything. Normally it would drop down a list of all the bones and sockets in the SkeletalMesh.

I assume what’s happening is that the Parent Socket selector can’t tell that the BIK component internally contains a SkeletalMesh which is what typically populates the Parent Socket drop down.

[anonymous_user_9db26c75]

Hi, I am interested to test your plugin too, do you plan to add options for more advanced foot placement with IK on the ankle and the toe like ikinema? Also they have automatic balance that they are adding to the $99 version, do you plan to do this too in the future?

[darkZ]

Hi Troywar,

Yes advanced foot placement for the ankle is coming with an update scheduled to be released early this week. Can you described the toe IK a bit more ?

Also, automatic balancing is definitely planned for the future.

There’s a push in this plugin towards more autonomous behaviors for both player and NPCs which will use the underlying IK to produce smart locomotion and task manipulation behaviors. (Real time smart procedural motion planning using task-aware locomotion and full body IK - YouTube )

You can check current roadmap here : Trello

Best,