Legibility changes

[Georacer]

This PR is two small legibility improvements in TECS.cpp

It also adds small typo fixes I did while reading TECS.cpp.

[magicrub]

The K_thr2STE maths is not equivalent, just remove that bit now. The other changes look OK

[magicrub]

this is not equivalent. The const var is doing / and this one is doing *.

[Georacer]

I did the math on my mind, with pencil and paper and here too:

nomThr + STEdot_dem / (_STEdot_max - _STEdot_min) * (_THRmaxf - _THRminf) =
nomThr + STEdot_dem * (_THRmaxf - _THRminf) / (_STEdot_max - _STEdot_min) =
nomThr + STEdot_dem * ( (_THRmaxf - _THRminf) / (_STEdot_max - _STEdot_min) ) =
nomThr + STEdot_dem / ( (_STEdot_max - _STEdot_min) / (_THRmaxf - _THRminf) ) =
nomThr + STEdot_dem / K_thr2STE

Perhaps you can give it another look?

[Georacer]

Not sure why it fails the CI, though.

[tridge]

I think this is correct, should be checked again
@magicrub note the lack of () in the original, makes it on the numerator

[peterbarker]

Ping @magicrub

[peterbarker]

I tested this PR with this patch on top:

diff --git a/libraries/AP_TECS/AP_TECS.cpp b/libraries/AP_TECS/AP_TECS.cpp
index 9307502caaf..86a07566b7d 100644
--- a/libraries/AP_TECS/AP_TECS.cpp
+++ b/libraries/AP_TECS/AP_TECS.cpp
@@ -740,6 +740,10 @@ void AP_TECS::_update_throttle_with_airspeed(void)
         // Calculate gain scaler from specific energy error to throttle
         const float K_thr2STE = (_STEdot_max - _STEdot_min) / (_THRmaxf - _THRminf); // This is the derivative of STEdot wrt throttle measured across the max allowed throttle range.
         const float K_STE2Thr = 1 / (timeConstant() * K_thr2STE);
+        const float old_K_STE2Thr = 1 / (timeConstant() * (_STEdot_max - _STEdot_min) / (_THRmaxf - _THRminf));
+        if (!is_zero(K_STE2Thr-old_K_STE2Thr)) {
+            abort();
+        }
 
         // Calculate feed-forward throttle
         const float nomThr = aparm.throttle_cruise * 0.01f;
@@ -750,6 +754,10 @@ void AP_TECS::_update_throttle_with_airspeed(void)
         const float cosPhi = sqrtf((rotMat.a.y*rotMat.a.y) + (rotMat.b.y*rotMat.b.y));
         STEdot_dem = STEdot_dem + _rollComp * (1.0f/constrain_float(cosPhi * cosPhi, 0.1f, 1.0f) - 1.0f);
         const float ff_throttle = nomThr + STEdot_dem / K_thr2STE;
+        const float old_ff_throttle = nomThr + STEdot_dem / (_STEdot_max - _STEdot_min) * (_THRmaxf - _THRminf);
+        if (!is_zero(ff_throttle-old_ff_throttle)) {
+            abort();
+        }
 
         // Calculate PD + FF throttle
         float throttle_damp = _thrDamp;

... and there were not aborts.

Merging as agreed on DevCall last night.