{"id":726,"date":"2019-08-30T08:21:05","date_gmt":"2019-08-30T07:21:05","guid":{"rendered":"https:\/\/www.martyndavis.com\/?p=726"},"modified":"2019-09-09T14:56:38","modified_gmt":"2019-09-09T13:56:38","slug":"controlling-a-lathe-with-c","status":"publish","type":"post","link":"https:\/\/www.martyndavis.com\/?p=726","title":{"rendered":"Controlling a Lathe with C++"},"content":{"rendered":"\n

This is a quick post – I’m intending on going into far more detail about this at a later stage – but recently, for fun, I’ve been working on automating some functions on a metalworking lathe. It’s been a really interesting project – I’ve been driving a fairly powerful stepper motor to give accuracy of positioning of tooling down to near-micron level, and measuring the position of the lathe’s spindle (via a rotary encoder) while it spins, at an accuracy required to start a cut at the same position over multiple passes, for cutting threads. I’ve been driving all this from a Raspberry Pi 3 Model B. It’s working beautifully, as you can see from the thread I cut below:<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

From a C++ perspective, this has required microsecond-level accuracy, and plenty of multi-threading to get suitable real-time performance – it’s interesting to have a real-world requirement for this kind of coding outside of my normal work, and incredibly rewarding to see the lathe chuck spinning in a blur but knowing that the code can determine exactly what its rotational position is at any moment.<\/p>\n\n\n\n

Usage of mock objects and unit tests have allowed me to develop large chunks of the code without access to the hardware when I’m away from my workshop.<\/p>\n\n\n\n

The code can be found at https:\/\/github.com\/md81544\/electronicLeadScrew<\/a><\/p>\n\n\n\n

See the thread cutting in action at https:\/\/www.youtube.com\/watch?v=VlhPiRscNeY<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

This is a quick post – I’m intending on going into far more detail about this at a later stage – but recently, for fun, I’ve been working on automating some functions on a metalworking lathe. It’s been a really interesting project – I’ve been driving a fairly powerful stepper motor to give accuracy of … <\/p>\n

Continue reading “Controlling a Lathe with C++”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"_links":{"self":[{"href":"https:\/\/www.martyndavis.com\/index.php?rest_route=\/wp\/v2\/posts\/726"}],"collection":[{"href":"https:\/\/www.martyndavis.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.martyndavis.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.martyndavis.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.martyndavis.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=726"}],"version-history":[{"count":7,"href":"https:\/\/www.martyndavis.com\/index.php?rest_route=\/wp\/v2\/posts\/726\/revisions"}],"predecessor-version":[{"id":736,"href":"https:\/\/www.martyndavis.com\/index.php?rest_route=\/wp\/v2\/posts\/726\/revisions\/736"}],"wp:attachment":[{"href":"https:\/\/www.martyndavis.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=726"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.martyndavis.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=726"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.martyndavis.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=726"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}