PG Schema to be used as log and monitoring store

Hi,

Given this kind of sensors (Internet-of-Things) log and monitoring scenario:

* There are 3 production machines monitored every few seconds for
forthcoming (~2) years.
* Machine m1 is emitting 20 boolean and 20 float4 captured in sensors
(m1s1..m1s40).
* Machine m2 has same attributes as m1 plus 10+10 more (m2s1..m2s20).
* Machine m3: like m2 but half of the attributes are different.
* Queries are happening once every day, like:
  SELECT m1s1,m1s2 FROM m1 WHERE logged BETWEEN '2017-11-01' AND '2017-11-30'".

So this is a kind of an "Immutable DB" with where there are
* rather static schema with sources which have overlapping attributes
* heavy writes,
* periodic reads

Would you model this schema also like my proposition, which saves
place but makes it little bit more complex to insert/update due to the
arrays?

  create table m1 (
    id bigint,
    created timestamp,
    b20 bit(20) default b'00000000000000000000',
    farr20 float8[20]
  );

:Stefan