Page 341 - Mechatronics with Experiments

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JWST499-c05
JWST499-Cetinkunt
ELECTRONIC COMPONENTS FOR MECHATRONIC SYSTEMS 327
9. Consider a data acquisition system that samples signals from various sensors. Let us assume
the following: there are four sensors to be sampled. The voltage outputs from each sensor are in the
following ranges for sensors 1 through 4: ±10 VDC, ±1 VDC, 0 to 5 VDC, and 0 to 2 VDC. Expected
maximum frequency content in each signal is 1 kHZ, 100 Hz, 20 Hz and 5 Hz for sensor 1 through 4,
respectively. The error introduced due to sampling should not be more than ±0.01% (1 part in 10 000)
of the maximum value of the signal. Determine the specifications for a 4-channel ADC (analog to
digital converter) for this application that will meet the requirements. Specifiy the minimum sampling
rate for each channel (according to the sampling theorem) and recommend a practical sampling rate
for each channel.
10. Consider the RL and RC circuits shown in Figure 5.5c, d, respectively. The switch in each
circuit is connected to the supply voltage (A side) and B side at specified time instants. Assume the
following circuit parameters; L = 1000 mH = 1000 × 10 −3 H = 1H, C = 0.01 μF = 0.01 × 10 −6 F,
R = 10 kΩ. Let the supply voltage be V (t) = 24 VDC. Assume in each circuit, the initial condition
s
on the current is zero and initial charge in the capacitor is zero. Starting time is t = 0.0 s. At time
o
t = 100 μs the switch is connected to the supply, and at time t = 500 μs, the switch is disconnected
1
2
from the supply and connected to the B side of the circuit. Plot the voltage across each component
and current as a function of time for the time period of t = 0.0s to t = 1000 μs.
0
f