Week 2

The different ways to simulating the circuit and the assembly of the real circuit in the 2^nd week

In this week our group found that the PSPICE software is not very suitable for the simulation of our project. We spent half of a day to simulate but finally failed to get a appropriate output. On the other hand, some components such as LM1458 amplifiers are not in the database of PSPICE. Creating a new model can be in convenient. So we changed PSPICE to Multisim. Then a new simulation can be processed easier and correctly. The circuit is shown below.

Sine wave was applied to be a simulative input to represent human’s movement. The wave-forms below as an oscilloscope are input and output. The output signal is affected by the amplifier and the comparator. This is only a simple process to test the availability of the circuit system. To achieve the goal of detect the variation of the human’s movement need to utilize more complex inputs.

After simulation, our group attempted to assemble to build the circuit on the breadboard. Using an oscilloscope to display the output signal.

But the output signal is in correct and there is no reflection when sensor detect the human motion. We will check each part of the circuit next week, and modify it.