Week3

Week 10: Input Devices
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	As with all electronic circuit boards we start with milling out the boards. Since I have the milling process figured out, I decided to try to cut circuits on copper foil instead of using the Modella Mill.
	I started with the "standard settings" on the vinyl cutter. This is the new end of the roll and as a result the copper may be lifting off because of this. More experimentation was needed.
	I changed the blade from a 45 degree 60 degrees. I still had a lot of lifting. I changed from a speed of 8cm and pressure of 90 grams to a speed of 4cm and 110 grams. Still no luck
	Using a lower force of 60 grams and a speed of 2 cm produced better results but there was still some lifting of the copper foil and there were places where the cuts did not go all the way through the copper.
	The final trials included 60 grams of force and a speed of 2cm with 2 cutting passes. This left dented lines in the copper and nothing more. The final trial was with 70 grams of force a speed of 2cm and multiple cuts. This produced lifting in finer areas and not enough blade penetration in others. I will return to the problem at at later date.
	I used the Modela mill to mill 4 input circuit devices. I chose to start with the light sensor.
	I started with the microphone and was unable to make any progress. Either the board is flawed or I am having trouble with the code. I noted from the emails that others were having trouble with the microphone so I switched to the light sensor.
	The light sensor is soldered and ready to go.
	I have success at hooking up the sensor to the computer. The software is working fine. I am able to see a window on my computer screen waiting to read sensor output. However I run into an error as per the code below. More work is needed: avrdude: 502 bytes of flash written avrdude: verifying flash memory against hello.light.45.c.hex: avrdude: load data flash data from input file hello.light.45.c.hex: avrdude: input file hello.light.45.c.hex auto detected as Intel Hex avrdude: input file hello.light.45.c.hex contains 502 bytes avrdude: reading on-chip flash data: Reading \| ################################################## \| 100% 0.20s avrdude: verifying ... avrdude: 502 bytes of flash verified avrdude: safemode: Fuses OK avrdude done. Thank you. make: warning: Clock skew detected. Your build may be incomplete. croppm@ubuntu:~/Desktop/Sensfile10$ Blair and Anna are helping troubleshoot the problem. I am trying to get the the program to recognize the port I am using. croppm@ubuntu:~/Desktop/Sensfile10$ python hello.light.45.py /dev/ttyUSB Traceback (most recent call last): File "hello.light.45.py", line 62, in <module> ser = serial.Serial(port,9600) File "/usr/lib/python2.7/dist-packages/serial/serialutil.py", line 260, in __init__ self.open() File "/usr/lib/python2.7/dist-packages/serial/serialposix.py", line 276, in open raise SerialException("could not open port %s: %s" % (self._port, msg)) serial.serialutil.SerialException: could not open port /dev/ttyUSB: [Errno 2] No such file or directory: '/dev/ttyUSB' croppm@ubuntu:~/Desktop/Sensfile10$ I have the python sensor appearing on the desktop. When I look in the Sensfile10 folder I have 2 new files. One is hello.light.45.c.hex the other is hello.light.45.out The next step is to type the USB port in correctly. I need to watch capitalization, use correct paths, and be very precise on my coding instructions. The process will continue.
	I did some troubleshooting with Abu and with Anna. There are several items to look for when completing this unit. They are: Use Notepad++ and be sure to save files as Make files. Plain notepad converts files to text even if/when you do not choose this option. Make sure the ports you are plugged into are the ones identified in the code Double check to make sure your syntax - particularly paths - are correct between what you saved and where you saved it. The syntax and your paths need to match.
When all of the issues are resolved the program works well. The red bar moves up and down as the sensor is covered or exposed to light..
	Clicking on the image to the left will link you to a video of the sensor working.