Hold hmd(vive) Position and Rotation ?

hi,
I'm trying to freeze(hold) the vive's position and rotation in the unity scene,
Is there a way to override the hmd(vive) position and rotation for holding specified position and rotation value..?
I'm using steam vr asset.

Previously, i made a render texture(from other camera) and follow the texture in front of hmd(vive) like below code,

void Update()
{
Vector3 pos = hmd.transform.position
+ hmd.transform.forward * distance.z
+ hmd.transform.up * distance.y
+ hmd.transform.right * distance.x;

Quaternion rot = hmd.transform.rotation;

frontobj.transform.position = pos;
frontobj.transform.rotation = rot;
}

the render textured mesh is located in front of hmd(vive), but the textured mesh is shaking and
fluttering in the hmd(vive) screen ( it's okay in the unity editor screen, but not okay in the hmd(vive) screen )

So, i trying to find a way to freeze or hold the hmd(vive) position and rotation for alternative method..