code: public JSONObject construct(){
          JSONObject payload = new JSONObject();
          payload.put(Names.MAIN_BRUSH.toString(), mainBrushWorkTime);
          payload.put(Names.SENSOR.toString(), sensorTimeSinceCleaning);
          payload.put(Names.SIDE_BRUSH.toString(), sideBrushWorkTime);
          payload.put(Names.FILTER.toString(), filterWorkTime);
          return payload;
      }
docs: Construct the message the vacuum sends to the controlling device.
  @return The constructed message.