Source Code
017952,000001: # Copyright: Public domain.
017953,000002: # Filename: GIMBAL_LOCK_AVOIDANCE.agc
017954,000003: # Purpose: Part of the source code for Comanche, build 055.
017955,000004: # It is part of the source code for the Command Module's (CM)
017956,000005: # Apollo Guidance Computer (AGC), Apollo 11.
017957,000006: # Assembler: yaYUL
017958,000007: # Reference: pp. 412-413
017959,000008: # Contact: Onno Hommes <ohommes@cmu.edu>.
017960,000009: # Website: www.ibiblio.org/apollo.
017961,000010: # Mod history: 05/07/09 OH Transcription Batch 1 Assignment
017962,000011:
017963,000012: # The contents of the "Comanche055" files, in general, are transcribed
017964,000013: # from scanned documents.
017965,000014:
017966,000015: # Assemble revision 055 of AGC program Comanche by NASA
017967,000016: # 2021113-051. April 1, 1969.
017968,000017:
017969,000018: # This AGC program shall also be referred to as Colossus 2A
017970,000019:
017971,000020: # Prepared by
017972,000021: # Massachusetts Institute of Technology
017973,000022: # 75 Cambridge Parkway
017974,000023: # Cambridge, Massachusetts
017975,000024:
017976,000025: # under NASA contract NAS 9-4065.
017977,000026:
017978,000027: # Refer directly to the online document mentioned above for further information.
017979,000028: # Please report any errors to info@sandroid.org.
017980,000029:
017981,000030:
017982,000031: # Page 412
017983,000032: 15,2000 BANK 15
017984,000033: 22,2000 SETLOC KALCMON1
017985,000034: 22,2000 BANK
017986,000035:
017987,000036: 22,2737 E6,1661 EBANK= BCDU
017988,000037:
017989,000038: # DETECTING GIMBAL LOCK
017990,000039: 22,2737 22,2737 LOCSKIRT EQUALS WCALC
017991,000040: 22,2737 70740 WCALC LXC,1 DLOAD*
017992,000041: 22,2740 01130 RATEINDX
017993,000042: 22,2741 04771 ARATE,1
017994,000043: 22,2742 45002 SR4 CALL # COMPUTE THE INCREMENTAL ROTATION MATRIX
017995,000044: 22,2743 44530 DELCOMP # DEL CORRESPONDING TO A 1 SEC ROTATION
017996,000045: # ABOUT COF
017997,000046: 22,2744 74343 DLOAD* VXSC
017998,000047: 22,2745 04771 ARATE,1
017999,000048: 22,2746 03343 COF
018000,000049: 22,2747 77721 MXV
018001,000050: 22,2750 05003 QUADROT
018002,000051: 22,2751 17311 STODL BRATE
018003,000052: 22,2752 03365 AM
018004,000053: 22,2753 55605 DMP DDV*
018005,000054: 22,2754 05001 ANGLTIME
018006,000055: 22,2755 04771 ARATE,1
018007,000056: 22,2756 77661 SR
018008,000057: 22,2757 20606 5
018009,000058: 22,2760 27317 STOVL TM
018010,000059: 22,2761 03311 BRATE
018011,000060: 22,2762 77761 VXSC
018012,000061: 22,2763 05025 BIASCALE
018013,000062: 22,2764 03275 STORE BIASTEMP # ATTITUDE ERROR BIAS TO PREVENT OVERSHOOT
018014,000063: # IN SYSTEM
018015,000064: 22,2765 77614 SETGO # STATE SWITCH CALCMAN2 (43D)
018016,000065: 22,2766 01035 CALCMAN2 # 0(OFF) = BYPASS STARTING PROCEDURE
018017,000066: 22,2767 45032 NEWANGL +1 # 1(ON) = START MANEUVER
018018,000067:
018019,000068:
018020,000069: 22,2770 00044 15053 ARATE 2DEC .0022222222 # = .05 DEG/SEC
018021,000070:
018022,000071: 22,2772 00221 24255 2DEC .0088888889 # = .2 DEG/SEC
018023,000072:
018024,000073: 22,2774 00554 02660 2DEC .0222222222 # = .5 DEG/SEC
018025,000074:
018026,000075: 22,2776 02660 13301 2DEC .0888888889 # = 2 DEG/SEC $22.5 DEG/SEC
018027,000076:
018028,000077: 22,3000 00003 04000 ANGLTIME 2DEC .000190735 # = 100B - 19
018029,000078:
018030,000079: # MANEUVER ANGLE TO MANEUVER TIME
018031,000080: 22,3002 03146 14632 QUADROT 2DEC .1 # ROTATION MATRIX FROM S/C AXES TO CONTROL
018032,000081:
018033,000082: # Page 413
018034,000083: 22,3004 00000 00000 2DEC 0 B-28 # AXES (X ROT = -7.25 DEG)
018035,000084:
018036,000085: 22,3006 00000 00000 2DEC 0 B-28
018037,000086:
018038,000087: 22,3010 00000 00000 2DEC 0 B-28
018039,000088:
018040,000089: 22,3012 03131 11275 2DEC .099200 # =(.1)COS7.25
018041,000090:
018042,000091: 22,3014 77461 47370 2DEC -.012620 # =-(.1)SIN7.25
018043,000092:
018044,000093: 22,3016 00000 00000 2DEC 0 B-28
018045,000094:
018046,000095: 22,3020 00316 30407 2DEC .012620 # (.1)SIN7.25
018047,000096:
018048,000097: 22,3022 03131 11275 2DEC .099200 # (.1)COS7.25
018049,000098:
018050,000099: 22,3024 00004 05253 BIASCALE 2DEC .0002543132 # = (450/180)(1/0.6)(1/16384)
End of include-file GIMBAL_LOCK_AVOIDANCE.agc. Parent file is MAIN.agc