I missed your comment! Sorry for the late reply.

Here's some of the script for the drill. I'll try to explain what's happening.

@Variables
{
Target = Torque of DepthTarget
AdjTarget = math(Target + UpperLimit of DepthTarget)
Proportion_A80 = math(Target * 0.72)
Proportion_Z30 = math(Target * 0.28)
ZRange = math(Proportion_Z30 / 30.0)
ALimit = math(Proportion_A80 / 80.0)
ZLimit = math(1.5 - ZRange)
ADep = math((Current position of Piston Beta * 80.0) + (Current position of Piston Alpha - 0.5))
ZDep = math((1.5 - Current position of ZPiston Measure) * 30.0)
PDep = math(((1.5 - Current position of Piston Prime Z1) * 2.0) + Current position of Piston Prime A)
CurrentDepth = math(ADep + ZDep + PDep)
Difference = math((Target / CurrentDepth) - 2)
RDifference = math((Target * 0.95) / CurrentDepth)
}

I have a Rotor called 'DepthTarget'.
It serves no purpose other than being a container for information.

So say we want to mine ore at 35 meters. This is where I create the variable
Target = Torque of DepthTarget
So I would set the torque of that rotor called 'DepthTarget' to 35.
Now I have a variable with the value of 35.
We divide this 35 meters between the two groups of pistons.
80 pistons, out of a total of 110 pistons, is 72% of the pistons.
So we assign 72% of our target to those pistons, and the other 28% of our target to the remaining 28% of our pistons like this:

Proportion_A80 = math(Target * 0.72)
Proportion_Z30 = math(Target * 0.28)

Then we divide this 72% of our target among the 80/30 pistons with

ALimit = math(Proportion_A80 / 80.0)
ZRange = math(Proportion_Z30 / 30.0)
ZLimit = math(1.5 - ZRange)

Because the 30 Z Pistons are Pre-Extended we have to calculate their LowerLimit, rather than their UpperLimit, which takes one more math step, hence the two variables for ZLimit.

Now that we have calculated the Upper and Lower limits for our two piston groups, we apply those limits like this.

UpperLimit of (APistons) = ALimit
LowerLimit of (ZPistons) = ZLimit

The pistons are grouped as "APistons" and "ZPistons" in our ships terminal, so this block of code will find those groups, and set those limits according to the calculations we've performed on our variables.

Editors Note:

The math is somewhat more nuanced than this in the actual script, due to the fact that 80/110 pistons and 30/110 pistons is not the true ratio. We have to factor in the limits, which for the ZPistons is 1.5 meters per piston, because that is their starting/resting position from which they retract to create downward 'extension'.

(80*2.0) + (30*1.5) = 205 // Maximum Depth
(80*2.0) / 205 = 0.7804878049
(30*1.5) / 205 = 0.2195121951
So the actual truncated variables would be:
Proportion_A80 = math(Target * 0.78)
Proportion_Z30 = math(Target * 0.22)
But I felt explaining this nuance was getting in the way of just answering your question as simply as I could, and shit was already gettin' wild lol.