Setting up SteamVR without HMD

reference https://vvvv.org/blog/using-htc-vive-trackers-without-headset

Edit D:/Documents/Steam/steamapps/common/SteamVR/resources/settings/default.vrsettings

Edit the following fields

    ...
    "steamvr": {
        "requireHmd": false,
        ...
    },
    ...  
    "driver_imu": {
        "enable":  true
    },
    ...

Next, edit file D:/Documents/Steam/config/steamvr.vrsettings

Add the following lines in steamvr field

      "activateMultipleDrivers" : false,
      "forcedDriver" : "null",

After change:

   "steamvr" : {
      "activateMultipleDrivers" : false,
      "forcedDriver" : "null",
      "installID" : "18301835954502125344",
      "lastVersionNotice" : "2.2.3",
      "lastVersionNoticeDate" : "1703041472",
      "showAdvancedSettings" : true
   },

Restart SteamVR. Might need to add controller again

Then it will look like this