From 3afe34b95f9d84da69a4884c2c01e5f32d7edb5b Mon Sep 17 00:00:00 2001
From: topquark12 <aw@m-labs.hk>
Date: Sat, 26 Dec 2020 11:06:52 +0800
Subject: [PATCH 1/4] changes to error calculation, polarity of kP and kI will
 be flipped

---
 src/pid.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/pid.rs b/src/pid.rs
index 996c538..503ad4c 100644
--- a/src/pid.rs
+++ b/src/pid.rs
@@ -60,7 +60,7 @@ impl Controller {
         let time_delta = time_delta.get::<second>();
 
         // error
-        let error = input - self.target;
+        let error = self.target - input;
 
         // proportional
         let p = f64::from(self.parameters.kp) * error;
-- 
2.44.1


From 3e859ecafbc0b963284221c6749cfb2eee1c691d Mon Sep 17 00:00:00 2001
From: topquark12 <aw@m-labs.hk>
Date: Sat, 26 Dec 2020 11:09:09 +0800
Subject: [PATCH 2/4] added anti integral windup and changed how the integral
 term is calculated

---
 src/pid.rs | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/pid.rs b/src/pid.rs
index 503ad4c..dc1ea9c 100644
--- a/src/pid.rs
+++ b/src/pid.rs
@@ -66,14 +66,21 @@ impl Controller {
         let p = f64::from(self.parameters.kp) * error;
 
         // integral
-        self.integral += f64::from(self.parameters.ki) * error * time_delta;
+        if let Some(last_output_val) = self.last_output
+        {
+            //anti integral windup
+            if last_output_val < self.parameters.output_max.into() && last_output_val > self.parameters.output_min.into()
+            {
+                self.integral += error * time_delta;    
+            }
+        }
         if self.integral < self.parameters.integral_min.into() {
             self.integral = self.parameters.integral_min.into();
         }
         if self.integral > self.parameters.integral_max.into() {
             self.integral = self.parameters.integral_max.into();
         }
-        let i = self.integral;
+        let i = self.integral * f64::from(self.parameters.ki);
 
         // derivative
         let d = match self.last_input {
-- 
2.44.1


From a632fc3a8e42ad054d28ccee6978039c6dab9e66 Mon Sep 17 00:00:00 2001
From: topquark12 <aw@m-labs.hk>
Date: Sat, 26 Dec 2020 11:25:05 +0800
Subject: [PATCH 3/4] fix formatting

---
 src/pid.rs | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/pid.rs b/src/pid.rs
index dc1ea9c..cc8a56c 100644
--- a/src/pid.rs
+++ b/src/pid.rs
@@ -66,9 +66,8 @@ impl Controller {
         let p = f64::from(self.parameters.kp) * error;
 
         // integral
-        if let Some(last_output_val) = self.last_output
-        {
-            //anti integral windup
+        if let Some(last_output_val) = self.last_output {
+            // anti integral windup
             if last_output_val < self.parameters.output_max.into() && last_output_val > self.parameters.output_min.into()
             {
                 self.integral += error * time_delta;    
-- 
2.44.1


From eb5b7470508ea5d54b798384290b523604e4778e Mon Sep 17 00:00:00 2001
From: topquark12 <aw@m-labs.hk>
Date: Sat, 26 Dec 2020 11:26:53 +0800
Subject: [PATCH 4/4] fix l71 formatting

---
 src/pid.rs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/pid.rs b/src/pid.rs
index cc8a56c..f23d636 100644
--- a/src/pid.rs
+++ b/src/pid.rs
@@ -68,8 +68,7 @@ impl Controller {
         // integral
         if let Some(last_output_val) = self.last_output {
             // anti integral windup
-            if last_output_val < self.parameters.output_max.into() && last_output_val > self.parameters.output_min.into()
-            {
+            if last_output_val < self.parameters.output_max.into() && last_output_val > self.parameters.output_min.into() {
                 self.integral += error * time_delta;    
             }
         }
-- 
2.44.1