fix(bkgpslog):Fix float calc in buffer PID adjust

[EVA-2020-02.git] / exec / bkgpslog

diff --git a/exec/bkgpslog b/exec/bkgpslog
index db8af896939b24dd57473ba416c925cf9fcb43bd..7a4487fd872bfcea28fbf833f56ae1181fff5b09 100755 (executable)
--- a/exec/bkgpslog
+++ b/exec/bkgpslog
@@ -28,11 +28,7 @@ declare -a argRecPubKeys # for processArguments function
 
 ## Initialize variables
 OPTION_VERBOSE=""; OPTION_ENCRYPT=""; OPTION_COMPRESS=""; OPTION_TMPDIR="";
-errResetx10e3=0; BUFFER_TTL_ADJ_FLOAT="";
-### PID Control factors
-K_P=10; # Gain for compensating buffer round lag
-T_I=2; # Consider this number of past buffer rounds to eliminate error
-T_D=1; # Predict value this number of buffer rounds into the future
+errReset=0; BUFFER_TTL_ADJ_FLOAT="";
 
 #===BEGIN Declare local script functions===
 checkapp() {
@@ -950,16 +946,21 @@ magicBufferSleepPID() {
     # ## Define errorHistorySize
     # errorHistorySize=100;
     ## Define BUFFER_TTL in nanoseconds
-    BUFFER_TTL_NS=$((BUFFER_TTL * 10**9));
+    BUFFER_TTL_NS=$((BUFFER_TTL * 10**9)) && vbm "BUFFER_TTL_NS:$BUFFER_TTL_NS";
+
+    ### PID Control factors
+    K_P=1; # Gain for compensating buffer round lag
+    T_I="$((4*BUFFER_TTL_NS))"; # Consider this number of past nanoseconds to eliminate error
+    T_D="$((1*BUFFER_TTL_NS))"; # Predict value this number of nanoseconds into the future
     
     # Calculate Error, errNS, in nanoseconds
     ## Get current time
-    timeBufferStartNS="$(timeEpochNS)";
+    timeBufferStartNS="$(timeEpochNS)" && vbm "timeBufferStartNS   :$timeBufferStartNS";
     ## Calculate expected time (from start time, current buffer round number, nominal BUFFER_TTL)
-    timeBufferStartNSExp="$(( (timeBufferFirstNS) + (BUFFER_TTL_NS * bufferRound) ))";
+    timeBufferStartNSExp="$(( (timeBufferFirstNS) + (BUFFER_TTL_NS * bufferRound) ))" && vbm "timeBufferStartNSExp:$timeBufferStartNSExp";
     ## Calculate error (diff between timeBufferStartNSExp and timeBufferStartNS; usually negative)
-    errNS="$(( timeBufferStartNSExp - timeBufferStartNS ))";
-    errNSx10e3="$((errNS*10**3))";
+    errNS="$(( timeBufferStartNSExp - timeBufferStartNS ))" && vbm "errNS:$errNS";
+#    errNSx10e3="$((errNS*10**3))" && vbm "errNSx10e3:$errNSx10e3";
     # ## Append error to errorHistory
     # errorHistory+=("errNS");
     # ### Trim errorHistory array if over errorHistorySize
@@ -975,25 +976,37 @@ magicBufferSleepPID() {
     # for value in "${errorHistory[@]}"; do
     #  errReset=$(( errReset + ( value*BUFFER_TTL_NS ) ));
     # done;
-    errResetx10e3="$(( ( errResetx10e3 + ( errNS * BUFFER_TTL_NS ) )*10**3 ))";
+    errReset="$(( (errReset + (errNS*BUFFER_TTL_NS)) ))" && vbm "errReset:$errReset";
+#    errResetx10e3="$(( ( errResetx10e3 + ( errNSx10e3 * BUFFER_TTL_NS ) )*10**3 ))" && vbm "errResetx10e3:$errResetx10e3";
 
-    # Calculate errRate in nanoseconds per 1000 nanoseconds
-    errRatex10e3="$(( ( errNSx10e3 ) / BUFFER_TTL_NS ))";
+    # Calculate errRate in nanoseconds per nanosecond
+    errRate="$(( errNS / BUFFER_TTL_NS ))" && vbm "errRate:$errRate";
+#    errRatex10e3="$(( ( errNSx10e3 ) / BUFFER_TTL_NS ))" && vbm "errRatex10e3:$errRatex10e3";
     
     # Calculate PID control signal
     ## ADJ = K_P * (errNS + errReset/T_I + errRate*T_D)
-    ADJ="$((K_P*(errNSx10e3 + (errResetx10e3/T_I) + (errRatex10e3*T_D) )/10**3))";
+    ADJ="$(( K_P*(errNS + errReset/T_I + errRate*T_D) ))" && vbm "ADJ:$ADJ";
+#    ADJ="$((K_P*(errNSx10e3 + (errResetx10e3/T_I) + (errRatex10e3*T_D) )/(10**3)))" && vbm "ADJ:$ADJ";
 
     # Calculate BUFFER_TTL_ADJ_FLOAT from ADJ (ns)
     ## Calculate BUFFER_TTL_ADJ in nanoseconds (BUFFER_TTL_ADJ_NS = BUFFER_TTL_NS + ADJ)
-    BUFFER_TTL_ADJ_NS="$((BUFFER_TTL_NS + ADJ))";
+    BUFFER_TTL_ADJ_NS="$((BUFFER_TTL_NS + ADJ))" && vbm "BUFFER_TTL_ADJ_NS:$BUFFER_TTL_ADJ_NS";
     ## Calculate integer seconds
-    BUFFER_TTL_ADJ_INT="$((BUFFER_TTL_ADJ_NS/(10**9)))";
+    BUFFER_TTL_ADJ_INT="$((BUFFER_TTL_ADJ_NS/(10**9)))" && vbm "BUFFER_TTL_ADJ_INT:$BUFFER_TTL_ADJ_INT";
+    ### Catch negative integer seconds, set minimum of BUFFER_TTL/10 seconds
+    if [[ "$BUFFER_TTL_ADJ_INT" -le "$((BUFFER_TTL/10))" ]]; then
+       BUFFER_TTL_ADJ_INT="$((BUFFER_TTL/10))";
+       yell "WARNING:Buffer lag adjustment yielded negative seconds.";
+    fi;
     ## Calculate nanosecond remainder
-    BUFFER_TTL_ADJ_FLOATFRAC="$((BUFFER_TTL_NS - (BUFFER_TTL_ADJ_INT*(10**9)) ))";
+    ### Remove integer
+    BUFFER_TTL_ADJ_FLOATFRAC="$((BUFFER_TTL_ADJ_NS - (BUFFER_TTL_ADJ_INT*(10**9)) ))";
+    ### Calc absolute value of fraction (by removing '-' if present; see https://stackoverflow.com/a/47240327
+    BUFFER_TTL_ADJ_FLOATFRAC="${BUFFER_TTL_ADJ_FLOAT_FRAC#-}" && vbm "BUFFER_TTL_ADJ_FLOATFRAC:$BUFFER_TTL_ADJ_FLOATFRAC";
     ## Form float BUFFER_TTL_ADJ_FLOAT
-    BUFFER_TTL_ADJ_FLOAT="$BUFFER_TTL_ADJ_INT"."$BUFFER_TTL_ADJ_FLOATFRAC";
+    BUFFER_TTL_ADJ_FLOAT="$BUFFER_TTL_ADJ_INT"."$BUFFER_TTL_ADJ_FLOATFRAC" && vbm "BUFFER_TTL_ADJ_FLOAT:$BUFFER_TTL_ADJ_FLOAT";
     vbm "STATUS:Calculated adjusted BUFFER_TTL (seconds):$BUFFER_TTL_ADJ_FLOAT";
+    sleep 1 # Debug
 } # Calc BUFFER_TTL_ADJ_FLOAT so buffer starts every BUFFER_TTL seconds
 magicWriteVersion() {
     # Desc: Appends time-stamped VERSION to PATHOUT_TAR
@@ -1309,13 +1322,13 @@ main() {
     CMD_CONV_KML="gpsbabel -i nmea -f - -o kml -F - " && vbm "STATUS:Set CMD_CONV_KML to:$CMD_CONV_KML"; # convert NMEA to KML
 
     # MAIN LOOP:Record gps data until script lifespan ends
-    timeBufferFirstNS="$(timeEpochNS)"; bufferRound=0
+    timeBufferFirstNS="$(timeEpochNS)"; bufferRound=0; BUFFER_TTL_ADJ_FLOAT="10.0";
     while [[ "$SECONDS" -lt "$SCRIPT_TTL" ]]; do
        magicParseRecipientDir;
        magicGatherWriteBuffer &
-       magicBufferSleepPID; # Calculates BUFFER_TTL_ADJ from BUFFER_TTL given buffer expected start time vs. actual
        sleep "$BUFFER_TTL_ADJ_FLOAT";
        ((bufferRound++));
+       magicBufferSleepPID; # Calculates BUFFER_TTL_ADJ from BUFFER_TTL given buffer expected start time vs. actual
     done    
 
     # Cleanup