Upload
chris-ashley
View
277
Download
0
Embed Size (px)
Citation preview
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 1/64
to be
rerromagneuc materials, for example, elements Iron, Cobalt and Nickel, have a
neighbouring-atoms tend to have axes of their molecular
magnets aligned same direction. A g ro up o f a lig ne d mo lecu les is termed a
"domain". Each d om ain is only a " fr ac ti on o f a m i ll ime tr e across so in a samp le
the domains may be random ly orientated or they may be aligned some extent. That is,
th e m aterial m ay b e u nm ag netised , o r it may h av e some m ag netism in du ced it .
HARD AhTI SOFT IRON
" ''h en ferroma gn etic m ate rial is p lace d in an ex tern al field some o f'th e d om ain s b ecom e
a ligned ""i th th e e xte rn al fie ld . Ifth e field in creases m ore d om ain s b ecome alig ned u ntilfinally all of the doma in s a re ful ly l ined up with th e ex tern al field an d th e m aterial b ecomes
saturated w ith m agnetism . T he manner in which this induction occurs and the le vel o f
field necessary for saturation lead to the idea of H ard iron and S oft iron, The sketch on
the next page illustrates the f oll ow ing t erms.
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 2/64
FLUX. ..,DENSITY
o;;1'\'!"""".,(H) out allco ncen trated at some
distance pole . F lux: d en sity o r Induc tion
is the am ount' of flux passing through an area
one square m etre at right angles to the flux.
The units are W b/m2 and the sym bol is B.
lNDUCTION
PERMEABILITY This is sim ply a ratio of flux density produced to inducing
field strength. It m easures how easily flux is created in th e
material or m edium . It can be thought of as the slope of the
hys te re sis loop.
The symbol fo r p ermeab ility is J . t an d u nits are n ot u su ally co nsid ered .
E ven m aterials w hich are norm ally considered non m agnetic can support m inute am ounts
ie they are very slightly permeable. a rule permeability of vacuum or "The
to be the to are
\
:::; x
or
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 3/64
aor
are
are
are
are is in a
2
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 4/64
3: Like Poles End On
5: t!1'I!!k~ Side Side
3
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 5/64
4
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 6/64
. 1 1 ) ; ; ,$
'! I
~ '"
')
ff""'I""",4
*) ' 'f
. ' 1
~ 4>f'1
'I \ «1
L. J
\'j~
,i
8: Molecular domain
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 7/64
6
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 8/64
can
1
as
10: The Elements
t~~
he.
7
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 9/64
are
across
a
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 10/64
is
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 11/64
a
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 12/64
13: P Force
14: Q Force .
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 13/64
15: R Force
12
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 14/64
on
p
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 15/64
/'
E
on
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 16/64
16: Directive Force
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 17/64
17.
17: Deviation due to soft iron effect
16
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 18/64
18:
17
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 19/64
'1 8
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 20/64
GHylBAL
CAP & P!VOT
BOWL
STAND
8UCKET
IvlA.,GNETIC
19:
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 21/64
it
ora
is
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 22/64
20:
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 23/64
close to the horizon,
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 24/64
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 25/64
Deviation
o o o e
0100
020"
030"
0400
050"
0600
070"
0800
0900
1000
1100
120"
5 " '1M
1 E
2° E
4" E
5° E
7" E
50 E
1300
1400
50°
1600
1 "10°
i80°
1° VV
1" E
2°W
3aW
SoW
SoW
4°W
2°W
200"
2100
2200
230"
24000"
2" E
1W.5 00
2600 2 ,0 V ' .l
1 ' -' E
280" 3" E
3° E90'~300"
2° E
340· 1" E
1° E
0"
3500
3600
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 26/64
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 27/64
Gyrocompass Revision )
Across
~6. Result of
~10.
",11. Force
12.
~'·13
around vertical axis
horizontal motion of
(2 words)
of ft on r andom latitude
in which re to
.,.,14. Path of
Down
,..1
~2.
·,·3.
,.'4.1 : : :
.,~. " ... .) '"
listie sys tem
very large moment of inert
of one of the earth (2 words)
under influence of control pzece ss
of gyro' 8 •
···9.
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 28/64
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 29/64
Gyrocompass Revision (2)
Across
Reduct; of
ir .~
(2 'ida
error
Off-set ion to
" 14.
in wh.icn
is suspended
A-frame
rotor casing in
east/west direction (2
words)
Damping error (2
Down
"""~ MearlS
- 9~.
~"10.
az
of
se
tial tiea
1
f1.() \~
central arm of E-
tr ans former
of ccnt act s s
s mo+.or
1 . ~ Force of tilt: in
16.
vertical
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 30/64
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 31/64
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 32/64
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 33/64
T I,lS can b e exoram ec as fo llow s:
the
combin ed v ec to r v, and therefore A w ill not
pass the horizontal of the rotor in P, but
in A'. At that same moment, B is at
the bottom of the rotor and
reasonmg, will p as s t he ho riz on ta l
etc. the in which the
~ t. can
8 .
pass the horizontal of therotor rotates around the
vertical axis and the rotor is said
to p recess in th e h orizo ntal
"r,Y".,."nu to the double-arrows.
When the
the distance between A'
and B' will decrease will
between A' and B' w m increase
increases ,...hile 'V i stays the
and the will
increase.
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 34/64
=
momentum
T
H =
a
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 35/64
s N
it name:
to be to use
to
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 36/64
E
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 37/64
meridian
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 38/64
can now
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 39/64
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 40/64
a
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 41/64
Attached to the rotor filled with a mercury because of its
to the south ofthe horizontal east-west axis. North-south
at their bases. The are also connectedat their upper ends to allow of air pressure in the of the pots. The whole is
about the east-west axis and the centre of mass of the ballistic system must coincide with that of the rotor
when the rotor is horizontal.
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 42/64
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 43/64
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 44/64
IS
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 45/64
P c 1 0 Ih e w elS l
~
F (not vsrtica!)
P c Line
b y
meridian
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 46/64
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 47/64
meridian
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 48/64
errors
error:
error.
error:
(per
Az is
cos
error:
courses
on courses
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 49/64
error:
cos B
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 50/64
A =-vcos
rad
courses
coursesAls
A=
cos
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 51/64
=
=f
= f.15
lat
error:
IS same as
error
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 52/64
c an c au se errors
error.
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 53/64
shipsails this direction
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 54/64
a
Schematic gyrocompass
2. Phantom 3. A-FnlmelVertk:a!
6, Soft-iron armature; 7. f.:,-;;;l1aneOHorizontal
1 . 2 . Azimuth gear; 3. Azimuth motor; 14. Control
i6.
F>W
15.
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 55/64
vertical
im::!ucedcurrent coil Ii
v'-&u.n;~current
vertical
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 56/64
to
as
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 57/64
to
transmitter receiver motor
compass
. .. -
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 58/64
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 59/64
NEW IN
IS
on
3. A to steer the course at
to auto the ship should be on the course
overswing.
IS
at'".,,; ,1'
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 60/64
course
(
course error,
Settings are
Again,
slow
will depend upon weather, size of
best guide, rememoen
ships considerably. too much rudder
and overshooting the new course, too little rudder results in slow alterations
and possible course errors.
loaded or etc,
on
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 61/64
or Ii on
course to s te er .
a set
courses to
on
to o n (
to autopilot to warn the or out
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 62/64
E
(bl In circumstances as above, it bewatch to have without delay
at times to
l e i
versaCDlaIIQf'l-r,VElI from automatic to manual
made by or
The manualautomatic pilot, and
t'caution.
HJ1~"·nLL use of~""4~~U demands
Automatic Pilots,
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 63/64
R
R R
E
,\'I
o on
R
to R
is set out in the
for Automatic Pilots,
to
STANDARDS FOR
2.
2.1
a n y
8/3/2019 Gyro and Compass
http://slidepdf.com/reader/full/gyro-and-compass 64/64
Res.
is ino
3.
amount,
Id a n
in
o r c ou rse
3.4 signalling facilities should near
4.
4,' a n d
automatic adjustments are incorporated
provided with adequate controls
and the performance.
in stallation , th e au to -use to
ld not
Id
5 .