! TITLE: ground_load.mac (MMA WBDDS) ! !----------------------------------------------------------------------- ! Rev - 08/19/2006 D. Edwards !----------------------------------------------------------------------- ! ! Kinematics & Kinetics model of MMA Weapons Bay Doors and Linakges. ! ! Usage: ground_load,Adoor ! ! Adoor: Angle [0, 95] of outboard door from the closed position ! ! If no argument is supplied, the model will be solved with a zero deg ! door angle. ! ! ! CS_0: Cartesian aircraft reference point Coordinate System ! CS_1: Cylindrical aircraft reference point Coordinate System ! CS_2: Spherical aircraft reference point Coordinate System ! ! Ref: Boeing_model-2006-07-18.drw ! !************************** TABLE OF CONTENTS ************************** ! ! Model Assembly Preparation ! ! 1. Parameter List ! 2. Model Coordinate System ! 3. Elements ! 4. Constraints ! 5. Solution ! 6. Post Processing ! !********************* Model Assembly Preparation ********************** ! mod_assemb_prep !,arg1,arg2,arg3 ! prepare database for assembly ! Adoor=arg1 ! Initial door angle (Adoor=0 @ fully closed) ! !<<<<<<<<<<<<<<<<<<<<<<<< 1. Parameter List >>>>>>>>>>>>>>>>>>>>>>>>>> ! ground_load.parm ! !<<<<<<<<<<<<<<<<<<<< 2. Model Coordinate System >>>>>>>>>>>>>>>>>>>>> ! mod_coord_system,acs,xc,yc,zc,rotxyc,rotyzc,rotzxc ! Turn on KP and line numbers & switch to front view. /pnum,node,1 /pnum,elem,1 /view,1,,,1 /ang, 1 /rep,fast ! !<<<<<<<<<<<<<<<<<<<<<<<<<<< 3. Elements >>>>>>>>>>>>>>>>>>>>>>>> ! ! ! Create KPs at aircraft mount points (fixed pivots) ! csys,0 k,1,y1,z1 nkpt,1,1 k,4,y4,z4 nkpt,4,4 k,26,y26,z26 nkpt,26,26 ! ! Create the Gooseneck Link ! create_cs,2,'CS1_1',1,y1,z1 ! k,2,Lgoose,Adoor0+Adoor nkpt,2,2 ! e,1,2 ! Gooseneck link ! ! Create the Load Link and RGA output link ! csys,CS1_1 create_cs,0,'CS2_1',1,Lgoose,Adoor0+Adoor,0,180 ! Cylindrical CS @ node 2 k,100,Llink,((29-96)/95*Adoor+90)-20 ! Construct an arc @ 2 k,101,Llink,((29-96)/95*Adoor+90)+20 larc,100,101,2,Llink create_cs,2,'CS4_1',1,y4,z4 ! Construct an arc @ 4 k,102,Lrga,((230-75)/95*Adoor+75)-20 k,103,Lrga,((230-75)/95*Adoor+75)+20 larc,102,103,4,Lrga ! Joint 3 is at the intersection of the two arcs linl,1,2 ! Create KP 3 at joint 3 nkpt,3,3 nkpt,20,2 ! Create node at KP 2 nkpt,30,3 ! Create node at KP 3 e,20,30 ! Load link e,4,3 ! RGA output ! ! Create the outer door ! csys,CS1_1 k,31,Ldo1,Adoor0+Adoor+Ado+Ado1 ! Location of outer door CG nkpt,31,31 e,1,31 k,24,Ldo,Adoor0+Adoor+Ado nkpt,24,24 e,31,24 ! ! Create Strut and Inner Door ! nkpt,240,24 ! Node for inner door @ KP 24 create_cs,2,'CS26_1',1,y26,z26 ! Swing an arc for strut k,104,Lstrut,((132-56)/95*Adoor-132)-20 k,105,Lstrut,((132-56)/95*Adoor-132)+20 larc,104,105,26,Lstrut csys,0 create_cs,2,'CS24_1',1,kx(24),ky(24) k,106,Ldi,135 k,107,Ldi,225 larc,106,107,24,Ldi !lplot linl,1,2 !KP=5 nkpt,25,5 e,26,25 ! Strut nkpt,250,5 csys,CS24_1 ! Define location of inner door CG create_cs,0,'CS240_1',1,0,0,0,ky(5) k,32,Ldi1,Adi1 nkpt,32,32 e,240,32 ! Create the inner door e,32,250 ! Compute moment arm for load link about RGA driveline (d1) csys,0 l,2,3 ln_dist_kp,'d1',1,4 ! Compute moment arm for load link about hingeline (d2) csys,0 ln_dist_kp,'d2',1,1 ! ! Create the bottom skin of the inner door for use in calculating ! the projected height for the wind load calculation ! csys,CS240_1 k,110,Ldisc,Adisc ! Inner door skin center k,111,Ldis1,Adis1 ! Outboard corner k,112,Ldis2,Adis2 ! Inboard corner larc,111,112,110,Rdis ! ! Mass elements ! ! Outer door type,2 mat,2 real,2 e,31 ! Inner Door real,3 e,32 ! !<<<<<<<<<<<<<<<<<<<<<<<<<<< 4. Constraints >>>>>>>>>>>>>>>>>>>>>>>>>> ! ! Aircraft structure constraints nsel,s,node,,1 nsel,a,node,,26 d,all,ux,0,,,,uy ! Completely fix the RGA output allsel d,4,all ! ! Constrain all the links together ! cpintf,ux cpintf,uy /pbc,all,,1 eplot ! !<<<<<<<<<<<<<<<<<<<< 5. Solution >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> ! fini /solu acel,0,g_bin antype,static outres,all,all solve fini ! !<<<<<<<<<<<<<<<<<<<< 6. Post Processing >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> ! /post1 ! ! Process text results ! ! Strut angle from horizontal csys,CS26_1 Astrut=ny(25) ! RGA out angle from door closed position csys,CS4_1 Arga=ky(3)-Arga0 *if,Arga,lt,0,then Arga=360+Arga *endif ! Calculate projected height for wind load calculation csys,0 *if,ky(111),lt,ky(112),then Height=ny(1)-ky(111) *else Height=ny(1)-ky(112) *endif ! Reaction moment on RGA output due to door weight *get,Mrga,NODE,4,RF,Mz ! Record position of CGs csys,0 CGoy=nx(31) CGoz=ny(31) CGiy=nx(32) CGiz=ny(32) ! ! Process graphics results ! round_num,Mrga,0 a1=num_ round_num,Arga,1 a2=num_ /title,MMA RGA torque due to ground loads: Mrga = %a1% (Adoor = %Adoor% Arga = %a2%) /pbc,rfor,,1 !/dscale,,1 !plnsol,rot,z,2,1.0 !/out,mma,out !prnsol,dof !prnld,,,all !presol,elem !/out