Electronic Throttle Body Details (#290)

* Update ETB-PID.md

Added details for etbStatus_Output and ETB: Duty explaining their function and how they are derived.

* Update ETB-PID.md

* Update ETB-PID.md

* Update ETB-Bias-Table.md

* Update ETB-Bias-Table.md

* Update ETB-PID.md

* Update Charge-Temp-Estimation.md

Added detail and screenshots.

* satisfy markdown linter

* Add files via upload

for direct reference

* Update Charge-Temp-Estimation.md

Reference images from repo

* Update Charge-Temp-Estimation.md

Corrected an issue with the wrong value, provided clarity on the values for the example under Air Mass Interpolation (linear) mode.

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Co-authored-by: Nathan Schulte <nmschulte@desmas.net>

docs/07-Advanced-Features/ETB/ETB-Bias-Table.md

@@ -1,3 +1,3 @@
 # Electronic Throttle Bias Table
 
-ETB feed forward setup  
+The Electronic TB Bias Table/ETB Bias Curve (Feed Forward) is calculated using the _ETB Target_ value to determine the duty bias. This duty bias is added to the output of the ETB PID loop to arrive at the final ETB duty. Values in this table range from -100% to 100%. 

docs/07-Advanced-Features/ETB/ETB-PID.md

@@ -1 +1,27 @@
 # ETB PID and Autotune
+
+## PID Settings
+
+### pFactor, iFactor, dFactor
+
+These are the Proportional, Integral and Derivative gains which apply to the Electronic Throttle Body (ETB) PID loop. Tuning these settings will affect how the ETB reacts. They output on log variables _etbStatus_pTerm_, _etbStatus_iTerm_ and _etbStatus_dTerm_ respectively.
+
+### pid min, pid max
+
+When the ETB PID loop updates, the pFactor, iFactor, and dFactor outputs are added together. They are clamped by _pid min_ and _pid max_ and will never be less than _pid min_ or greater than _pid max_.
+
+### iTermMin, iTermMax
+
+Similar to _pid min_ and _pid max_, these values apply specifically to the _iFactor_ output. The result of _iFactor_ will never be less than _iTermMin_ or greater than _iTermMax_.
+
+## PID AutoTune
+
+## Log Variables
+
+### etbStatus_output
+
+This value is the sum of all of the etbStatus_pTerm, etbStatus_iTerm and etbStatus_dTerm values. This value is clamped to upper and lower limits by _pid min_ and _pid max_. It is added to the _ETB Bias Curve_ value to give the final _ETB: Duty_ output.
+
+### ETB: Duty
+
+The sum of _etbStatus_Output_ added to the _ETB Bias Curve_ value.

docs/07-Advanced-Features/Fuel-Related/Charge-Temp-Estimation.md

@@ -1 +1,39 @@
-# Charge Temperature Estimation  
+# Charge Temperature Estimation
+
+Charge temperature estimation is used to model the increase in intake air temperature after the IAT sensor by the heat of the intake piping, intake manifold, cylinder head, etc. Without accurate charge temperature estimation it is possible that an engine may exhibit leaner air fuel ratios at higher IATs, especially under low load like idle and light cruise. This is common when the VE table is tuned at lower IATs without charge temperature estimation.
+
+## Mode
+
+Three modes of charge temperature estimation are available; _RPM+TPS_, _Air Mass Interpolation_ and _Table_.
+
+### RPM+TPS (Default)
+
+Interpolates between four coefficients based on RPM and TPS to generate a coefficient for estimating the intake air temperature. The coefficient determines the percentage of the estimated air temperature that comes from the IAT with the remainder coming from the CLT.
+
+![image](Charge-Temp-Estimation/cteRpmTpsMode.png)
+
+For example, a coefficient of 0.2500 means that 25% of the estimated air temperature is from the IAT, and 75% from the CLT. If the IAT was 40C and the CLT was 80C, the calculation for estimated air temperature would be `(40C * 0.25) + (80C * 0.75) = 70C`.
+
+A coefficient of 0.9000 (which may be used at high loads/RPM) would result in the calculation `(40C * 0.90) + (80C * 0.10) = 44C`. A coefficient of 1 means that the charge temperature estimate would be the same as IAT.
+
+### Air Mass Interpolation
+
+Also labeled as Airflow interpolation mode. This uses linear interpolation between the _low flow coefficient_ at zero flow and the _high flow coefficient_ at the _max air flow_ to calculate the balance between IAT and CLT to arrive at the final estimated air temperature. Similar to RPM+TPS, the calculated coefficient determines what percentage of the IAT makes up the charge temperature estimate.
+
+![image](Charge-Temp-Estimation/cteAirflowInterpolation.png)
+
+For example, a _low flow coefficient_ of 0.100, a _high flow coefficent_ of 0.900 and a _max air flow_ of 300 kg/h would result in a calculated coefficient of 0.5 at an air flow of 150 kg/h. This means that the charge temperature estimate would be a 50/50 split between IAT and CLT. At or above _max air flow_, the calculated coefficient would be 0.9. Similar to the above examples in RPM+TPS mode (40C IAT and 80C CLT), the resultant charge temperature estimate would be `(40C * 0.90) + (80C * 0.10) = 44C` at or above _max air flow_.
+
+### Table
+
+Uses a 2D table to return the charge temperature estimation coefficient based on the calculated flow rate. Similar to the above examples, the resultant charge temperature estimate is calculated by `(IAT * coefficient) + (CLT * [1 - coefficient])`.
+
+![image](Charge-Temp-Estimation/cteCoeff.png)
+
+## Increase rate limit, Decrease rate limit
+
+These settings control how quickly the charge temperature estimate value can increase or decrease to the new calculated value. The unit is degrees Celsius/second (degC/sec). Refer to the output _Air: Charge temperature estimate_. Note that there are two outputs with this name, one in degC and the other in degK.
+
+For example, if the current charge temperature estimate value is `40C` and the modeled charge temperature should be `50C`, an _increase rate limit_ of 1 deg/sec means that it would take 10 seconds for the charge temperature estimate value to increase from `40C` to `50C`.
+
+Conversely, if the current charge temperature estimate is `50C` and the modeled charge temperature changed back to `40C`, a _decrease rate limit_ of 5 deg/sec means that it would take 2 seconds for the charge temperature estimate value to decrease from `50C` to `40C`.