{"id":332761,"date":"2016-12-07T03:00:00","date_gmt":"2016-12-07T00:00:00","guid":{"rendered":"http:\/\/www.fyysika.ee\/?guid=4dabf4fdaa91a0040da61da9bd8c49d7"},"modified":"2016-12-07T03:00:00","modified_gmt":"2016-12-07T00:00:00","slug":"using-smartphone-pressure-sensors-to-measure-vertical-velocities-of-elevators-stairways-and-drones","status":"publish","type":"post","link":"https:\/\/www.fyysika.ee\/?p=332761","title":{"rendered":"Using smartphone pressure sensors to measure vertical velocities of elevators, stairways, and drones"},"content":{"rendered":"<p>We measure the vertical velocities of elevators, pedestrians climbing stairs, and drones (flying<br \/>\nunmanned aerial vehicles), by means of smartphone pressure sensors. The barometric pressure obtained<br \/>\nwith the smartphone is related to the altitude of the device via the hydrostatic approximation. From<br \/>\nthe altitude values, vertical velocities are derived. The approximation considered is valid in the<br \/>\nfirst hundred meters of the inner layers of the atmosphere. In addition to pressure, acceleration<br \/>\nvalues were also recorded using the built-in accelerometer. Numerical integration was performed,<br \/>\nobtaining both vertical velocity and altitude. We show that data obtained using the pressure sensor<br \/>\nis significantly less noisy than that obtained using the accelerometer. Error accumulation is also<br \/>\nevident in the numerical integration of the acceleration values. In the proposed experiments, the<br \/>\npressure sensor also outperforms GPS, because this sensor does not receive satellite signals indoors<br \/>\nan&#8230;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>We measure the vertical velocities of elevators, pedestrians climbing stairs, and drones (flying<br \/>\nunmanned aerial vehicles), by means of smartphone pressure sensors. The barometric pressure obtained<br \/>\nwith the smartphone is related to the altitude of th&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","footnotes":""},"categories":[178],"tags":[],"class_list":{"0":"post-332761","1":"post","2":"type-post","3":"status-publish","4":"format-standard","6":"category-rss-fuusikaharidus","7":"entry"},"_links":{"self":[{"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/posts\/332761","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=332761"}],"version-history":[{"count":0,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/posts\/332761\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=332761"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=332761"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=332761"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}