Need parent's rigidbody to ignore child's collisions etc

I currently have a cube that moves around, and a sphere above controlled with a LEAP motion device. basically, a player and a limb they can control.

I want to detect collisions when the sphere collides with anything, but the problem I have is that moving the sphere causes the cube to jump around; it’s affecting the cube’s physics/rigidbody.

I don’t want to have to remove the collider on the sphere, but obviously don’t want it affecting my player…

any ideas?

I’ve managed to solve it; I had to explicitly add a rigidbody component, and then set the rigidbody to is kinematic.

To explain my problem better:

what was happening: a player instantiated a “pointer” object, a child of the player that could move independent but relative to the player. this object would affect the physics of the player; wiggling the “pointer” object about in the air would cause the player to sway.

what i wanted: moving the “pointer” to not affect the physics of the player, while still being able to cause collision events

what solved it: manually adding a rigidbody to the pointer prefab, and setting is kinematic to true.

I might add a video of this later, but for now, it’s self-solved. Hope this helps anyone else who tries similar (I’m using leap motion controller, and this seems like a likely use case)