.PS
# Mechanics.m4
# https://tex.stackexchange.com/questions/761731/tizk-and-circuitikz-how-to-put-frame-around-collection-of-commands-inside
cct_init
#_init(Mechanics)
#nclude(tst.dim)

divert(-1)

Some simple electromechanical elements

                               `barrier( R|L|U|D|degrees, keys )
                                Hatched [ ] block in $1 direction with a line
                                  on first side
                                keys:
                                  wdth=expr; (dimen_/4)
                                  lgth=expr; (dimen_)
                                  line=attributes; (thick linethick*3/2)
                                  box=attributes; (e.g. dashed outline "color")
                                  hatchsep=expr; (4bp__)
                                  hatchspec=attributes;
                                  angle=degrees; (45) (relative to direction)'
define(`barrier',`[ setdir_(`$1')
 pushkeys_(`$2', wdth:dimen_/4; lgth:dimen_; line:thick linethick*3/2:N;
  box:invis:N; hatchsep:4bp__; hatchspec::N; angle:45;)
 Box: hatchbox(wid=m4lgth; ht=m4wdth; box=m4box;
        hatchsep=m4hatchsep; angle=m4angle;
        boxdir=rp_ang*rtod_`'ifinstr(m4_dir_,`t',,+90))
 Line: line by vec_(0,m4lgth) at Box+vec_(-m4wdth/2,0) m4line
 popdef(`m4wdth',`m4lgth',`m4line',`m4box',`m4hatchsep',`m4hatchspec',`m4angle')
 resetdir_ ]')

                                `damper( linespec, keys )
                                 Two-terminal element
                                 keys:  wdth=expr; (dimen_/4) body width
                                        lgth=expr; (wdth*5/4)
                                        body=attributes; body outline and fill
                                        plunger=attributes;'
define(`damper',`eleminit_(`$1')
 pushkeys_(`$2',`wdth:dimen_/4; lgth:(m4`'wdth)*5/4; body::N; plunger::N;') dnl
 if m4lgth > rp_len then { eleminit_(to rvec_(m4lgth,0)) }
 M4S: last line.start; M4E: last line.end; M4C: last line.c
 { line from M4S to (M4S+M4E)/2+vec_(m4lgth/6,0)
 {Body: [{ line thick linethick*3/2 by vec_(0,m4wdth*3/4) \
            with .c at Here m4plunger }
   line from rvec_(-m4lgth*2/3,m4wdth/2) by vec_(m4lgth,0) then \
    by vec_(0,-m4wdth) then by vec_(-m4lgth,0) m4body
   ] at rvec_(-m4lgth/6,0)}
  line from rvec_(m4lgth/3,0) to M4E}
 line invis to M4E popdef(`m4wdth',`m4lgth',`m4body',`m4plunger') ')

                                `spring( linespec, keys )
                                 keys:  type=S|R|C;
                                     S=sharp, R=rounded, C=coiled
                                   wdth=expr; body width
                                   cycles=expr;
                                   lgth=expr; default cycles*wdth
                                   body=attributes; box body'
define(`spring',`eleminit_(`$1')
 M4S: last line.start; M4E: last line.end; M4C: last line.c
 pushkeys_(`$2',`type:S:N; wdth:dimen_/5; cycles:4;
   lgth:(m4`'cycles)*(m4`'wdth)/2; body::N;')dnl
 if m4lgth > rp_len then { eleminit_(to rvec_(m4lgth,0)) }
  pushdef(`m4nN',`eval(2*m4cycles)') m4Rh=m4lgth/m4nN
  ifelse(m4type,S,
   `line to M4C+vec_(-m4nN*m4Rh/2,0); round
    [for_(2,m4nN,2,`line by vec_(m4Rh, m4wdth)ifelse(m4x,2,/2); round
       line by vec_(m4Rh,-m4wdth); round')
     line by vec_(m4Rh, m4wdth)/2; round] at M4C 
    line from M4C+vec_(m4nN*m4Rh/2,0) to M4E',
  m4type,R,
   `{ line to rvec_((rp_len-m4lgth)/2,0)
     M4coil: [ S: Here;
      round; spline ifdpic(0.55) to rvec_(0,m4wdth/2) \
      for_(1,m4cycles,1,`\
       then to rvec_((m4x+0.3)*m4Rh*2, m4wdth/2) \
       then to rvec_((m4x+0.3)*m4Rh*2,-m4wdth/2) \
       then to rvec_((m4x-0.3)*m4Rh*2,-m4wdth/2) \
       then to rvec_((m4x-0.3)*m4Rh*2,
         ifelse(m4x,eval(m4cycles),0,m4wdth/2))\')\
       then to rvec_(m4lgth,0); round ] with .S at Here
    line from M4S+vec_((rp_len+m4lgth)/2,0) to M4E }')
 line invis from M4S to M4E')
 popdef(`m4type',`m4wdth',`m4cycles',`m4body',`m4lgth',`m4nN')dnl
 ')

                                `coilspring( R|L|U|D|degrees, keys )
                                 keys: wdth=expr; lgth=expr; 
                                   cycles=expr;
                                   gauge=expr; wire thickness
                                   fcoil=attributes; front coils
                                   rcoil=attributes; rear coils'
define(`coilspring',`[ setdir_(`$1',R)
 pushkeys_(`$2',`wdth:dimen_/3; lgth:dimen_; cycles:6;
  gauge:m4`'lgth/m4`'cycles/4; fcoil:shaded "white":N;
  rcoil:shaded lightgray:N;') cycles=int(m4cycles)
  define lightgray {rgbstring(0.83,0.83,0.83)}
  fpitch=(m4lgth-m4gauge)/cycles
  tn=vlength(fpitch/2,m4wdth-m4gauge)
  cang = atan2(fpitch/2,m4wdth-m4gauge)*rtod_
  offset = m4gauge/2 + tn/2*fpitch/2/(m4wdth-m4gauge)
  for i=1 to cycles do { [setdir_(rp_ang*rtod_-cang)
    rotbox(m4gauge,tn+m4gauge,m4rcoil,r=m4gauge/2); resetdir_] \
    at vec_(offset+(i-0.5)*fpitch,0)}
  rotbox(m4gauge,m4wdth,m4fcoil,r=m4gauge/2) at vec_(m4gauge/2,0)
  for i=1 to cycles do { [setdir_(rp_ang*rtod_+cang)
    rotbox(m4gauge,tn+m4gauge,m4fcoil,r=m4gauge/2); resetdir_] \
    at vec_(offset+(i-1)*fpitch,0)}
  rotbox(m4gauge,m4wdth,m4fcoil,r=m4gauge/2) at vec_(m4lgth-m4gauge/2,0)
  popdef(`m4wdth',`m4cycles',`m4lgth',`m4gauge',`m4fcoil',`m4rcoil')dnl
  resetdir_ ] ')

                                `cart( R|L|U|D|degrees, keys )
                                 keys: wdth=expr; lgth=expr; 
                                   body=attributes;
                                   wheelrad=expr;
                                   wheels=attributes; '
define(`cart',`[ setdir_(`$1',R)
 pushkeys_(`$2',`wdth:boxwid; ht:boxht; body::N; wheelrad:m4`'ht/5; wheels::N;')
 Box: rotbox(m4wdth,m4ht,m4body)
 LC: circle rad m4wheelrad fill_(1) m4wheels at Box.SW+vec_( m4wheelrad*5/4,0)
 RC: circle rad m4wheelrad fill_(1) m4wheels at Box.SE+vec_(-m4wheelrad*5/4,0)
  popdef(`m4wdth',`m4ht',`m4body',`m4wheelrad',`m4wheels') resetdir_ ] ')

divert(0)dnl
[
moveht /= 2
  {damper; `"damper"' at last line.end ljust}
  move down_; right_
  {barrier(D); `"barrier(D)"' with .w at (last "".w,Here) ljust}
  move down_; right_
  {spring; "`spring'" at last line.end ljust}
  move down_; right_
  {spring(,type=R); "`spring(,type=R)'" at last line.end ljust}
  {cart with .nw at last line.start+(0,-moveht/2)
   "`cart'" at last [].Box.e ljust}
  ]
[
pivht = 1.2
pivwd = pivht*5/3
hingerad = 0.2*2/3
hingepinrad = 0.1*2/3
pivotrad = hingepinrad*3/2
pivotwid = pivotrad*2*2
pivotoffset = pivotrad*2
pratio = 3/2

BL: circle rad hingepinrad fill_(0)
TL: circle rad hingepinrad fill_(0) at BL+(0,pivht)
TR: circle rad hingepinrad fill_(0) at BL+(pivwd,pivht)
BR: circle rad hingepinrad fill_(0) at BL+(pivwd,0)
Pivot: circle rad pivotrad fill_(0) at 0.5<TL,TR>

# pivot structure
  line down pivotoffset from Pivot+(-pivotwid/2,pivotoffset)
  arc to Pivot+(pivotwid/2,0) with .c at Pivot
  line up pivotoffset
 T: barrier(U,lgth=pivotwid*3/2;wdth=0.15;hatchsep=6pt__;line=thick 1.5;
     angle=-45) with .s at Pivot+(0,pivotoffset)
thicklines_

# lower pivots
hingeoffset = hingerad*2/3
  line down hingeoffset from BL+(-hingerad,0)
  arc cw from BL+(-hingerad,0) to BL+( hingerad,0) with .c at BL
  line down hingeoffset
  
  line down hingeoffset from BR+(-hingerad,0)
  arc cw from BR+(-hingerad,0) to BR+( hingerad,0) with .c at BR
  line down hingeoffset

# base
#  hatchbox(invis wid pivwd+4*hingerad ht 0.2,.1) \
#    with .n at 0.5<BL,BR>+(0,-hingeoffset)
#thicklines_
 barrier(D,lgth=pivwd+4*hingerad; wdth=0.2; hatchsep=6pt__;line=thick 1.5;
     angle=-45) with .n at 0.5<BL,BR>+(0,-hingeoffset)
`"Tuned-mass damper"' at last [].s below

# mass dimensions
widM = (BR.x-BL.x)*3/5
htM = pivht*2/3
hangerwid = widM/2

# mass
M: box invis wid widM ht htM with .s at 0.5<BL,BR>+(0,hingerad)
dM = 0.1
  define lightgray {rgbstring(0.83,0.83,0.83)}
  line from M.ne+(-dM,0) to M.nw+(dM,0) then to M.nw+(0,-dM) \
    then to M.sw then to M.se then to M.ne+(0,-dM) then to M.ne+(-dM,0) \
    shaded rgbstring(0.83,0.83,0.83)

# horizontal arm
endwid = hingerad
  arc ccw from TL+(-hingerad,0) to TL+( hingerad,0) with .c at TL
  line right Pivot.x-hangerwid/2-Here.x then down Here.y-M.n.y
  arc cw from TR+( hingerad,0) to TR+(-hingerad,0) with .c at TR
  line left Here.x-Pivot.x-hangerwid/2 then down Here.y-M.n.y
  line from TR+( hingerad,0) up endwid then to (Pivot.x+pivotwid/2,TR.y+endwid)
  line from TL+(-hingerad,0) up endwid then to (Pivot.x-pivotwid/2,TR.y+endwid)

  define rust {rgbstring(183/255,65/255,14/255)}
S:coilspring(D,lgth=pivht*5/8;wdth=0.28;cycles=8;gauge=0.03;
    rcoil=shaded "gray"; fcoil=shaded rust) with .c at 0.5<BR,TR>
shaftwid = hingepinrad*3/2
shaftchop = sqrt(hingerad^2-shaftwid^2/4)
  move to S.n+(shaftwid/2,0); line to (Here,TR) chop 0 chop shaftchop
  move to S.n+(-shaftwid/2,0); line to (Here,TR) chop 0 chop shaftchop
  move to S.s+(shaftwid/2,0); line to (Here,BR) chop 0 chop shaftchop
  move to S.s+(-shaftwid/2,0); line to (Here,BR) chop 0 chop shaftchop

#D: box wid S.wid ht S.ht with .c at 0.5<BL,TL>
D: box wid S.wid ht S.ht shaded "YellowOrange" with .c at 0.5<BL,TL>
  move to D.n+(shaftwid/2,0); line to (Here,TL) chop 0 chop shaftchop
  move to D.n+(-shaftwid/2,0); line to (Here,TL) chop 0 chop shaftchop
  move to D.s+(shaftwid/2,0); line to (Here,BL) chop 0 chop shaftchop
  move to D.s+(-shaftwid/2,0); line to (Here,BL) chop 0 chop shaftchop

  "{\sl mass}" at M "$m$"
  `"\shortstack{\sl spring\\$k$}"' at S.e ljust #"$k$"
  "\shortstack{\sl d{}ashpot\\$b$}" wid 34.1pt__ at D.w rjust
  "{\sl pivot}" at T.w rjust
  move to 0.5<TR,Pivot>+(0.1,endwid/2)
  "$d$" at Here
thinlines_
  { arrow right 0.35 chop .06 }
  { arrow left  0.35 chop .06 }
  move to M.ne+(.1,0); move to (Here,(0.5<Pivot,M>))
  { arrow to (Here,Pivot) chop 0.08 chop 0}
  { arrow to (Here,M) chop 0.08 chop 0}
  "$\ell$"
  "$x,\,f$" at T.e ljust
  arrow right 0.35 from last "".w+(19.5pt__,0) chop textoffset
  ] with .w at 1st [].e+(1.25,0)
#howbox_

.PE