Specific gameobjects shuttering/jerking

my game character is continuously moving toward -ve y-axis by setting the gravity scale to 100 in its rigidbody2d. The character animation is running smooth and at specific points i instantiate some hurdles which are still. Problem is those hurdles while passing through the view, shutter a bit. As far as script is concerned, the camera is following the character.

void LateUpdate () { transform.position = new Vector3 (Mathf.Clamp(gamecharacter.position.x, xMin, xMax), Mathf.Clamp(gamecharacter.position.y, yMin, yMax),transform.position.z);

i dont know how to fix the hurdles shutter.

 }