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Message ID: 656     Entry time: Fri Jun 28 16:54:02 2013
Author: Giorgos 
Type: DailyProgress 
Category: SUS 
Subject: Low-pass filtering, Current booster, and Design of the Box Panels 

Today, we determined our low-pas filter circuits and its components. To achieve our cut-off filtering, we need to change the values of our zeroes and poles of the transfer function. Specifically, we saw that only if P1<Z0<P0 can we achieve low-pass filtering.Low-pass_filter_for_dewhitening.png

It is essential that are cut-off frequencies are very close to the values we used in our high-pass circuits, so that we achieve perfect de-whitening, especially for the two lowest cut-off values; we computed the values of our resistors and capacitors that yield such transfer functions and started wiring our 7 actuator PCB boards. However, the low-pass circuits cannot source a lot of current and so our PCB boards, apart from the low-pass filter, also include a current-booster circuit, which consists of the high-noise current buffer that is in a feedback loop with a low-noise op-amp. Later, we designed the box panels where we will place our 7 PCB actuator boards, along with 3 DC control boards, and 3 power boards.

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