For a while, I thought I could get away with not installing the limit switches.\u00a0 As long as I start the pendulum in the center, it does a very good job avoiding the ends.\u00a0 The problem is when I keep the pendulum inverted and it gets “bumped” repeatedly.\u00a0 While it is correcting for the bumps, it tends to get close to the end of the rack.\u00a0 Sometimes it will hit the end pretty hard while trying to correct for a bump.\u00a0 Once it hits the end, it loses the center reference and continues to get worse.\u00a0 I decided it was time to install the limit switches.<\/p>\n
Soldering the wires for the limit switches was a minor hassle.\u00a0 It wouldn’t have been too bad to solder three wires for each switch (GND, 5V, signal), but I needed a 1k ohm pull-up resistor between the 5V and the signal.\u00a0 It starts to be a large number of wires in each hole for the connector, and it is kind of difficult to work around the resistors.\u00a0 After the first try, I assembled the connector case and realized one wire was loose, so I had to take the connector case apart and resolder it.\u00a0 After the second try, I managed to get everything connected securely.\u00a0 Each signal turns off when the limit switch is obstructed, so I change the PWM limit in that direction to zero.\u00a0 It takes about the width of the limit switch for the cart to decelerate from full speed.\u00a0 If I position the limit switches just a short distance from the end, it will work well.\u00a0 Right now the switches are just taped in place, but I am working on permanently mounting them.\u00a0 My original plan was to drill holes and screw them down tight, but to do that I would probably have to move hardware out of the way to get the drill in place.\u00a0 It looks like it would be much easier to mount them with thick double sided tape.\u00a0 Not as pretty, but a heck of a lot easier.<\/p>\n","protected":false},"excerpt":{"rendered":"
For a while, I thought I could get away with not installing the limit switches.\u00a0 As long as I start the pendulum in the center, it does a very good job avoiding the ends.\u00a0 The problem is when I keep the pendulum inverted and it gets “bumped” repeatedly.\u00a0 While it is correcting for the bumps, […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[],"class_list":["post-244","post","type-post","status-publish","format-standard","hentry","category-software"],"_links":{"self":[{"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/posts\/244","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/comments?post=244"}],"version-history":[{"count":1,"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/posts\/244\/revisions"}],"predecessor-version":[{"id":245,"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/posts\/244\/revisions\/245"}],"wp:attachment":[{"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/media?parent=244"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/categories?post=244"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/tags?post=244"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}