There are various ways of measuring. My proposal for a metric is here:

http://machine-takeover.blogspot.com/2009/07/measuring-machine-takeover.html

I propose weighing them:

There are a variety of ways of measuring how much of the resource pie is allocated to machines.

One way that would appeal to economists is to look at the cost of constructing machines - and compare that to the cost of constructing humans. That would give an estimate of how much society is willing to spend on these different elements of the biosphere.

Here I will advocate what I believe to be a simpler method of measuring the proportion of machines on the planet. I think we should weigh them.

...in particular, weighing their sensor, motor, and computing elements.

...so "no" - not yet.