From: Sam Moore Date: Tue, 17 Sep 2013 03:09:11 +0000 (+0800) Subject: Notes from meeting X-Git-Url: https://git.ucc.asn.au/?a=commitdiff_plain;h=e98b2d71aa507c8656b47752a529a3a2a619875a;p=matches%2FMCTX3420.git Notes from meeting --- diff --git a/meetings/2013-09-17.txt b/meetings/2013-09-17.txt new file mode 100644 index 0000000..3db3834 --- /dev/null +++ b/meetings/2013-09-17.txt @@ -0,0 +1,51 @@ +Electronics + - What inputs will be provided + - 2x ADC channels, USB Hub (2 webcams?) + - What outputs are required + - 2x digital out for controlling multiplexers on ADCs + - Switch time for multiplexer? Affects sample rate + - 1x PWM to control DAC -> Analogue pressure regulator (?) + - 3x digital out for controlling solenoids + - Need to meet this week to work out sampling rate / antialiasing stuff + - Friday 12:00pm -> 2:00pm + - Wednesday 10:00am -> 11:00am + - Antialiasing: Need to sample at 2x rate we are interested in + - Accuracy of timestamps in software uncertain; should do some physical tests + - Estimates of BBB sampling rates vary, but from Jeremy's searches, the worst case: + - 34KHz for GPIO + - 100KHz for ADC + +Pneumatics + - What is being controlled -> Electronics + - Analogue controlled pressure regulator 0-5V + - 3 solenoids (on/off) + - Master valve (safety) + - 1 valve for each can (mutually exclusive, never allow both to be on at the same time) - need 12V for on, 20ms switch time, max freq 10Hz + - Electronics will probably use a multiplexer + - Will dump air when no power + - Diode protection needed + - When can fails, major drop in pressure will happen + - Should stop air supply when this is detected + - What is sensed? + - 3 x pressure sensors; 1 on main supply, 1 before each can + - Pressure limit of 100KPa on non-exploding can + - Safety threshold if sensor after this records > 100KPa + - No limit on exploding can + - Forgot to ask about *minimum* pressure values; use atmosphere (because if things fall below atmosphere they are probably broken)? + +Sensors + - Sensors -> Electronics -> Us + - Currently having argument with Adrian about use of interferometer or dilatometer + - Adrian will probably win the argument + - Image processing will be low priority for software until there is more certainty + - From a software point of view, interferometer and dilatometer are about the same difficulty + - Interferometer: Look for nodes (maximum change in intensity at laser wavelength) + - Dilatometer: Look for edge of can (maximum change in intensity of can colour) + - Laser light might be easier to process (larger intensity and larger intensity changes against dark background) + - But laser interferometer kit will definitely be harder to set up and align and position + - Sampling rate of images (stream only) - 20FPS (using Logicrap(TM) camera) + + +Case + - The software will fit + - There will be a hole for an ethernet cable