unitproc/bktemp-updateLoopPI

   1 #!/bin/bash
   2
   3 #==BEGIN function definition==
   4 yell() { echo "$0: $*" >&2; } # print script path and all args to stderr
   5 die() { yell "$*"; exit 111; } # same as yell() but non-zero exit status
   6 try() { "$@" || die "cannot $*"; } # runs args as command, reports args if command fails
   7 update_pi() {
   8     # Desc: Calculates control variable (CV) given setpoint (SP) and
   9     #   process variable (PV). Uses proportional integral (PI)
  10     #   control.
  11     # Usage: update_pi arg1 arg2 arg3 arg4 arg5
  12     # Version: 0.0.1
  13     # Input: arg1: path_loop_name (control loop name path)
  14     #        arg2: var_pv (process variable)
  15     #        arg3: var_sp (set point)
  16     #        arg4: tune_p (proportional tuning factor)
  17     #        arg5: tune_i (integral tuning factor)
  18     # Output: stdout: var_cv (control variable)
  19     #         file: path_var_pv
  20     #         file: path_var_sp
  21     #         file: path_tune_p
  22     #         file: path_tune_i
  23     #         file: path_sum (saves updated sum state)
  24     # Example: update_pi /dev/shm/DC1.AC 1.0 3.0 2.0 3.0
  25     # Depends: bc, gnu coreutils 8.30, yell(), try()
  26     local var_sp var_pv var_cv;
  27     local tune_p tune_i;
  28     local term_p term_i;
  29     local error sum;
  30     local path_sum path_var_sp path_var_pv path_tune_p path_tune_i;
  31
  32     path_loop_name="$1";
  33
  34     path_var_pv="$path_loop_name".pv
  35     var_pv="$2"; # read provided process variable
  36
  37     path_var_sp="$path_loop_name".sp
  38     if [[ -f "$path_var_sp" ]]; then
  39         var_sp="$(cat "$path_var_sp" | head -n1)";
  40     else
  41         var_sp="$3";
  42     fi;
  43
  44     path_tune_p="$path_loop_name".tune_p
  45     if [[ -f "$path_tune_p" ]]; then
  46         tune_p="$(cat "$path_tune_p" | head -n1)";
  47     else
  48         tune_p="$4";
  49     fi;
  50
  51     path_tune_i="$path_loop_name".tune_i
  52     if [[ -f "$path_tune_i" ]]; then
  53         tune_i="$(cat "$path_tune_i" | head -n1)";
  54     else
  55         tune_i="$5";
  56     fi;
  57
  58     path_sum="$path_loop_name".sum
  59     if [[ -f "$path_sum" ]]; then
  60         sum="$(cat "$path_sum" | head -n1)";
  61     else
  62         sum=0;
  63     fi;
  64
  65     #yell "DEBUG:path_loop_name:$path_loop_name";
  66     #yell "DEBUG:var_pv:$var_pv";
  67     #yell "DEBUG:var_sp:$var_sp";
  68     #yell "DEBUG:tune_p:$tune_p";
  69     #yell "DEBUG:tune_i:$tune_i";
  70
  71     error="$(try echo "$var_sp - $var_pv" | bc -l)";
  72     #yell "DEBUG:error:$error";
  73     sum="$(try echo "$sum + $error" | bc -l)";
  74     #yell "DEBUG:sum:$sum";
  75     term_p="$(try echo "$tune_p * $error" | bc -l)";
  76     #yell "DEBUG:term_p:$term_p";
  77     term_i="$(try echo "$tune_i * $sum" | bc -l)";
  78     #yell "DEBUG:term_i:$term_i";
  79     var_cv="$(try echo "$term_p + $term_i" | bc -l)";
  80     #yell "DEBUG:var_cv:$var_cv";
  81
  82     # Write variables to memory
  83     echo "$sum" > "$path_sum";
  84     echo "$var_sp" > "$path_var_sp";
  85     echo "$var_pv" > "$path_var_pv";
  86     echo "$tune_p" > "$path_tune_p";
  87     echo "$tune_i" > "$path_tune_i";
  88
  89     # Output control variable to stdout
  90     echo "$var_cv";
  91
  92     #yell "DEBUG:=============END_ROUND===============";
  93 }
  94 #==END function definition==
  95
  96 #==BEGIN Example code==
  97 path_loop_name="/tmp/DC1.AC";
  98 var_pv=1.0;
  99 var_sp=2.0;
 100 tune_p=1.0;
 101 tune_i=0.1;
 102 try rm "$path_loop_name"*
 103
 104 var_pv=4.0;
 105 output="$(update_pi "$path_loop_name" "$var_pv" "$var_sp" "$tune_p" "$tune_i" | tail -n1)";
 106 yell "DEBUG:sum:$(cat "$path_loop_name".sum | head -n1)";
 107 yell "DEBUG:output:$output";
 108 var_pv=4.0;
 109 output="$(update_pi "$path_loop_name" "$var_pv" "$var_sp" "$tune_p" "$tune_i" | tail -n1)";
 110 yell "DEBUG:sum:$(cat "$path_loop_name".sum | head -n1)";
 111 yell "DEBUG:output:$output";
 112 var_pv=4.0;
 113 output="$(update_pi "$path_loop_name" "$var_pv" "$var_sp" "$tune_p" "$tune_i" | tail -n1)";
 114 yell "DEBUG:sum:$(cat "$path_loop_name".sum | head -n1)";
 115 yell "DEBUG:output:$output";
 116 var_pv=4.0;
 117 output="$(update_pi "$path_loop_name" "$var_pv" "$var_sp" "$tune_p" "$tune_i" | tail -n1)";
 118 yell "DEBUG:sum:$(cat "$path_loop_name".sum | head -n1)";
 119 yell "DEBUG:output:$output";
 120 var_pv=4.0;
 121 output="$(update_pi "$path_loop_name" "$var_pv" "$var_sp" "$tune_p" "$tune_i" | tail -n1)";
 122 yell "DEBUG:sum:$(cat "$path_loop_name".sum | head -n1)";
 123 yell "DEBUG:output:$output";
 124 var_pv=1.0;
 125 output="$(update_pi "$path_loop_name" "$var_pv" "$var_sp" "$tune_p" "$tune_i" | tail -n1)";
 126 yell "DEBUG:sum:$(cat "$path_loop_name".sum | head -n1)";
 127 yell "DEBUG:output:$output";
 128 var_pv=1.0;
 129 output="$(update_pi "$path_loop_name" "$var_pv" "$var_sp" "$tune_p" "$tune_i" | tail -n1)";
 130 yell "DEBUG:sum:$(cat "$path_loop_name".sum | head -n1)";
 131 yell "DEBUG:output:$output";
 132 var_pv=1.0;
 133 output="$(update_pi "$path_loop_name" "$var_pv" "$var_sp" "$tune_p" "$tune_i" | tail -n1)";
 134 yell "DEBUG:sum:$(cat "$path_loop_name".sum | head -n1)";
 135 yell "DEBUG:output:$output";
 136 var_pv=1.0;
 137 output="$(update_pi "$path_loop_name" "$var_pv" "$var_sp" "$tune_p" "$tune_i" | tail -n1)";
 138 yell "DEBUG:sum:$(cat "$path_loop_name".sum | head -n1)";
 139 yell "DEBUG:output:$output";
 140 #==END Example code==
 141
 142 # Author: Steven Baltakatei Sandoval
 143 # License: GPLv3+