MyRobot Development Part 32 (Patreon)

Video shows the summary, text shows the technical!

This week:

• Hyper Realistic Finger Grabbing

• Physics Woes

Hyper Realistic Finger Grabbing

This was needed because the robot was not able to actually wrap its fingers around objects. It merely added a joint to glue the hand and the grabbed object together. But this now provides an additional step in the LateUpdate phase that allows the hand to physically grab the hand in an accurate fashion.

The system works with capsule colliders facing any direction x,y,z. However it ignores the spherical caps of the capsule and it only focuses on the body of the capsule.

Still, it covers 95% of all use cases which is perfect for now.

Physics Woes

 Ragdoll physics in games is hard. Very hard. I'm working with a ragdoll that can now grab onto things. This extends the number of chained joints on the arm limb and that makes it more difficult for Unity to solve.

In the past I've sunk many many hours trying to solve conceptually simple problems like how to make a rope, how to make ragdolls grab onto each other, how to make chains. Unity is just not built for these kinds of things. So it always comes down to making compromises.

The first thing I always do is remove physics. For example, in the past, I used to add a fixed joint to objects to glue them together. But because that creates chains of objects, I removed the physic component by simply combining both shapes into the same rigid body. This is how I was able to achieve many larva jumping on the robot and sticking to it without the physics spazzing out. They just become additional colliders instead of adding joints to the robot.

This week I had issues making the robot walk up to the washing machine and press a button. It's hard mostly because the arm or the robot can get stuck in everything. So I think I'm going to pivot and remove the physics by just having the robot play a washing machine animation when it gets close to it. That way I can manually animate and ensure no part of the robot will get stuck to any surrounding physics.

Also we got a few more drawings.

Stay tuned!