From 8be2ec95ab4fc9c14541bebc6a4b70cf074bc5c6 Mon Sep 17 00:00:00 2001
From: Steven Baltakatei Sandoval <baltakatei@gmail.com>
Date: Sun, 31 Oct 2021 22:16:49 +0000
Subject: [PATCH] fix(bktemp-updateloopPI):Add integral sum spike dampener

---
 unitproc/bktemp-updateLoopPI | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/unitproc/bktemp-updateLoopPI b/unitproc/bktemp-updateLoopPI
index bda89ee..61f7e8d 100644
--- a/unitproc/bktemp-updateLoopPI
+++ b/unitproc/bktemp-updateLoopPI
@@ -9,7 +9,7 @@ update_pi() {
     #   process variable (PV). Uses proportional integral (PI)
     #   control.
     # Usage: update_pi arg1 arg2 arg3 arg4 arg5 arg6
-    # Version: 0.1.1
+    # Version: 0.1.2
     # Input: arg1: path_loop_name (control loop name path)
     #        arg2: var_pv (process variable)
     #        arg3: var_sp (set point)
@@ -28,7 +28,7 @@ update_pi() {
     local var_sp var_pv var_cv;
     local tune_p tune_i;
     local term_p term_i;
-    local error sum;
+    local error sum sum_cand;
     local path_sum path_var_sp path_var_pv path_tune_p path_tune_i;
 
     path_loop_name="$1";
@@ -79,8 +79,13 @@ update_pi() {
     
     error="$(try echo "$var_sp - $var_pv" | bc -l)";
     #yell "DEBUG:error:$error";
-    sum="$(try echo "$sum + $error" | bc -l)";
+    sum_cand="$(try echo "$sum + $error" | bc -l)";
     #yell "DEBUG:sum:$sum";
+    if [[ "$(try echo "$sum_cand > 2 * $sum " | bc -l)" -eq 1 ]]; then
+	sum="$(try echo "$sum + l($error)" | bc -l)"; # dampen integral sum spikes
+    else
+	sum="$sum_cand";
+    fi;
     term_p="$(try echo "$tune_p * $error" | bc -l)";
     #yell "DEBUG:term_p:$term_p";
     term_i="$(try echo "$tune_i * $sum" | bc -l)";
-- 
2.30.2