Try to disable tracking position on occulus, don't find any doc on it.
I've search postionnal tracking, but nothing in aframe
https://github.com/aframevr/aframe/search?utf8=%E2%9C%93&q=tracking&type=
Maybe with THREE.JS?
This is not possible using any built-in A-Frame components, as of 0.8.0. What you're probably looking for is the look-controls component, which handles mouse and headset rotation/position.
There is an option to disable HMDs entirely, but none for just turning off position. You could request the feature or create your own version of look-controls, but I would be hesitant about that — it will make VR experiences much less comfortable for HMD users.