Spaces inside page ids are not valid, see
https://www.dokuwiki.org/pagename
You can generate new pages via this valid wikilinks:
[[metaldetector|Metal Detector]]
[[metal-detector|Metal Detector]]
[[metal.detector|Metal Detector]]
Maybe this could be interesting for you:
https://www.dokuwiki.org/config:useheading
https://www.dokuwiki.org/plugin:pagetitle