When using the standard Knowledge Base submission form, which is under Submit Request > Knowledge Base > Submit KB Entry, this includes only basic features. For example, images are not able to be attached. However, while logged in as an administrator, going to the Knowledge Base tab, there are extra buttons, such as Add Article, that offer enhanced features. For example, images are able to be attached. You want to know how to enable non-administrators to be able to use these enhanced features.
There is no out of box method for enabling enhanced features for the Submit KB Entry (the non-administrator Knowledge Base entry) form. This has been submitted as a feature request:
FEATURE REQUEST: Add ability to add images to standard Knowledge Base entry form
By default, only administrators have the ability to use the enhanced Knowledge Base features. Workarounds for this include adding permissions to the Knowledge Base Categories web part or adding the Portal.SuperAdmin permission to a group.
Workaround 1: Add permissions to the Knowledge Base Categories web part:
Workaround 2: Add the Portal.SuperAdmin permission to a group: