Automating Manufacturing Systems - Process Control and ...

continuous sensors - 23.41
6.
θ w
⎛ ⎞ ⎛ ⎞ 0V
a) V out
( V 2
– V 1
) ----------
42deg
= + V 1
= ( 5V – 0V)
------------------
300deg
+ = 0.7V
θ max
θ w
⎛ ⎞ 0V
b) 2.765V = ( 5V – 0V)
------------------
300deg
+
⎝
⎠
⎝
⎠
θ w
⎛ ⎞
⎝ ⎠
0V
2.765V = ( 5V – 0V)
------------------
300deg
+
θ w
= 165.9deg
⎝
⎠
7.
θ output
=
0.1-------------
deg
count
θ input
---------------
θ output
50
= ----- θ
1 input
= 50 0.1-------------
deg = 5-------------
deg
⎛ ⎞
count count
R
360 deg --------
rot
= ------------------
5-------------
deg = 72 count --------------
rot
count
⎝
⎠
8.
strain gauge measures strain in a material using a stretching wire that increases resistance
- accelerometers measure acceleration with a cantilevered mass on a piezoelectric
element.
9.
R
DMM V = K s
ω
+
-
When the motor shaft is turned by
another torque source a voltage is generated
that is proportional to the angular
velocity. This is the reverse emf. A dmm,
or other high impedance instrument can
be used to measure this, thus minizing
the loses in resistor R.
ω·
+ ω -----
K2 K
V s
⎛ ⎞
JR
=
----- ⎛ ⎞
JR
⎠
V s
= ω( K) + ω· JR ----- K
⎝
⎠
⎝
⎞
⎛
⎝
⎠