Mouse Dwell is a solution that allows a person with a physical difficulty to be able to use a mouse or other pointing device without the need to ever click a button. While the feature is traditionally especially useful for users of head pointers, it is also a proven accessibility tool for people who use mice, joysticks, rollerballs and any other pointing device.
Instead of having to press a mouse button or a switch the user needs to simply hold the mouse steady in an area for a predefined amount of time. This action issues the computer with a 'virtual' click and provides the same function as if someone had pressed the mouse button.
Mouse Dwell is not an accessibility feature built into Windows but there are a variety of free and commercially-available dwell solutions.
How steady you need to hold the pointer while waiting for the dwell depends on the software you are using. It is defined by the Dwell Time and the Target Size and these should be correctly tweaked and balanced for each individual if the options are available.
The dwell time is the amount of time a person has to wait before the virtual click is sent to the computer. Set too long a time and computer use can become frustratingly slow, and your user may not be able to hold the pointer steady for that long. Set too short a time and the virtual clicks could be sent inadvertently to other targets during brief pauses.
The target size is limited by the size of the key (for on-screen keyboards) or by a predefined 'target size' option (in dwell clickers that work globally). In the case of on-screen keyboards you should provide keys as large as possible for people who have tremors or otherwise struggle to hold the mouse steady.
We all desire some sort of feedback from computers when we're working with them. For example we need to see the hour glass to know that the computer is waiting and not simply crashed. Feedback is very important for mouse dwell users as it informs them that the computer has acknowledged their intention and indicates how long they have to hold the mouse steady until the click is accepted. Dwell programs use a variety of methods from Windows XP Keyboard's 'fill-up' to The Grid's 'clock':
Mouse Dwell is available as a third-party 'add-on' to Windows Accessibility or as part of an on-screen keyboard or in one case, The Gird, as both.
With most OSKs the dwell feature is limited to the keyboard itself and can not be used anywhere else on the screen. This means that unless your OSK can control other programs, like Clicker 4 but not Clicker 5, then your user would have to use the regular mouse click or an external switch to access menus, toolbars and launch programs. Clicker 4 actually provides a very useful 'mouse trapping' feature to forcibly keep the mouse pointer within the grid.
The exception to this rule is The Grid whose dwell delay feature also works outside the boundaries of the on-screen keyboard.
The following OSKs have a mouse dwell feature:
Global dwell programs work across the whole of the Windows operating system and all the program within it. These programs should be able to provide access to menus, icons, toolbars and even on-screen keyboards. Some global dwell programs have features that allow double-clicking and dragging as well as a regular standard click.
The following programs provide mouse dwell across the whole of Windows:
Please let me know if you know of any more, or have any other feedback on this article!
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