{"id":57,"date":"2023-02-11T23:05:18","date_gmt":"2023-02-11T23:05:18","guid":{"rendered":"http:\/\/course.ece.cmu.edu\/~ece500\/projects\/s23-teamb5\/?p=57"},"modified":"2023-02-13T16:09:54","modified_gmt":"2023-02-13T16:09:54","slug":"team-status-report-2-11-2023","status":"publish","type":"post","link":"http:\/\/course.ece.cmu.edu\/~ece500\/projects\/s23-teamb5\/2023\/02\/11\/team-status-report-2-11-2023\/","title":{"rendered":"Team Status Report 2\/11\/2023"},"content":{"rendered":"<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Risks<\/span>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">FPGA availability<\/span>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">FPGA chips were difficult to find, so we plan to switch to using a separate FPGA dev board or a microcontroller<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Dev board may have latency issues because high-speed communication will need to be sent back and forth over wires to a separate PCB<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Microcontroller speed\/data transmission also has a latency issue, because it\u2019s slower than FPGA<\/span>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">MCU speed: with the MSP430 that we\u2019ve used before, 25MHz is the fastest option.<\/span><\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">We could also use 2 microcontrollers to mitigate the speed issue, and use 1 per laser<\/span><\/li>\n<\/ul>\n<\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Plan: test out both the microcontroller and FPGA dev board in a separate setting to choose which option<\/span><\/li>\n<\/ul>\n<\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Component availability between early stage of design and component ordering<\/span>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Some components are low stock.\u00a0 We will order components once we are confident we will be using rather than ordering once our pcb design is released<\/span><\/li>\n<\/ul>\n<\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Lasers may not meet speed requirements<\/span>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">If not all components that we selected work, we will swap to a single laser setup using the one that works.\u00a0 We are confident that green will work because it has specs for modulation frequency, but the IR laser does not.\u00a0 We plan on testing this next week.<\/span><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Design Changes<\/span>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Change to FPGA<\/span>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">As described above, we were unable to find a FPGA to put on our custom PCB, so we will need to either use a FPGA dev board or MSP430 microcontroller.<\/span><\/li>\n<\/ul>\n<\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Not using sinusoidal modulation<\/span>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">We will instead send a square signal over the laser.\u00a0 This is because fiber optic laser drivers do this as well, so there is no commercially available IC to modulate a sinusoid with enough current to power our laser.<\/span><\/li>\n<\/ul>\n<\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Not use fiber optic laser driver<\/span>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">After creating a partial schematic and selecting support components for fiber optic drivers, it became clear that our application has a large number of changes required to manufacturer suggestions in order to work.\u00a0 Our project will be easier and more likely to succeed if we just create the driver circuits discretely rather than using a modified fiber optic driver circuit.<\/span><\/li>\n<\/ul>\n<\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Switch to 2 lasers: IR and green<\/span>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">We found that blue lasers are very expensive and there is only one with a low enough power rating for us, and it is most likely too slow.\u00a0 As a result, we switched to 2 lasers.\u00a0 Changing red to IR makes the gap in wavelength larger, so we can use commercially available photodiodes that only receive light at certain wavelengths to filter out the other color.<\/span><\/li>\n<\/ul>\n<\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Considering adding a higher voltage power supply<\/span>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">The green laser has a forward voltage over 5V.\u00a0 We are concerned about the effect that a boost converter will have on signal integrity, and do not consider our power supply to be the important part of our system.<\/span><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<li>Our project includes considerations for safety and security\n<ul>\n<li>Safety: The lasers must be of low enough power to not injure the eyes of users and bystanders<\/li>\n<li>Security: Our use case concerns itself with the secure transfer of private information. This method should ensure the private and secure transmission of data with minimal chance for remote interception.<\/li>\n<\/ul>\n<\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Schedule Changes<\/span>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Because we are unsure if we\u2019re using FPGA now, Anju will test out and set up environments for microcontrollers and FPGA to test out the parts for next week.<\/span><\/li>\n<\/ul>\n<\/li>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Photos<\/span>\n<ul>\n<li style=\"font-weight: 400\"><span style=\"font-weight: 400\">Starting to set up FGPA to test out compilation\u00a0<\/span><span style=\"font-weight: 400\"><img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-medium wp-image-65\" src=\"http:\/\/course.ece.cmu.edu\/~ece500\/projects\/s23-teamb5\/wp-content\/uploads\/sites\/232\/2023\/02\/FPGA-224x300.png\" alt=\"\" width=\"224\" height=\"300\" \/><\/span><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Risks FPGA availability FPGA chips were difficult to find, so we plan to switch to using a separate FPGA dev board or a microcontroller Dev board may have latency issues because high-speed communication will need to be sent back and forth over wires to a separate PCB Microcontroller speed\/data transmission also has a latency issue, &hellip; <\/p>\n<p class=\"link-more\"><a href=\"http:\/\/course.ece.cmu.edu\/~ece500\/projects\/s23-teamb5\/2023\/02\/11\/team-status-report-2-11-2023\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Team Status Report 2\/11\/2023&#8221;<\/span><\/a><\/p>\n","protected":false},"author":675,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[7],"tags":[3],"_links":{"self":[{"href":"http:\/\/course.ece.cmu.edu\/~ece500\/projects\/s23-teamb5\/wp-json\/wp\/v2\/posts\/57"}],"collection":[{"href":"http:\/\/course.ece.cmu.edu\/~ece500\/projects\/s23-teamb5\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/course.ece.cmu.edu\/~ece500\/projects\/s23-teamb5\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/course.ece.cmu.edu\/~ece500\/projects\/s23-teamb5\/wp-json\/wp\/v2\/users\/675"}],"replies":[{"embeddable":true,"href":"http:\/\/course.ece.cmu.edu\/~ece500\/projects\/s23-teamb5\/wp-json\/wp\/v2\/comments?post=57"}],"version-history":[{"count":8,"href":"http:\/\/course.ece.cmu.edu\/~ece500\/projects\/s23-teamb5\/wp-json\/wp\/v2\/posts\/57\/revisions"}],"predecessor-version":[{"id":71,"href":"http:\/\/course.ece.cmu.edu\/~ece500\/projects\/s23-teamb5\/wp-json\/wp\/v2\/posts\/57\/revisions\/71"}],"wp:attachment":[{"href":"http:\/\/course.ece.cmu.edu\/~ece500\/projects\/s23-teamb5\/wp-json\/wp\/v2\/media?parent=57"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/course.ece.cmu.edu\/~ece500\/projects\/s23-teamb5\/wp-json\/wp\/v2\/categories?post=57"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/course.ece.cmu.edu\/~ece500\/projects\/s23-teamb5\/wp-json\/wp\/v2\/tags?post=57"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}