User Requirements

	A	B	C
1	ID	Requirement text	Rationale
2	R_001	When the Advance button is pressed, the braille display will refresh to the next section	To allow users to manually advance to the next sentence
3	R_002	The device has an Autonomous mode toggle for all operations that can be used either manually and autonomously	This is an interface that allows the user to set the preference of whether they want to use buttons manually or have it operate autonomously
4	R_003	Upon physically reaching the end of a braille sentence, the display will automatically refresh to the next section if the Autonomous toggle is off	To read a book would otherwise require much manual operation of advancing the display, this way the user can read braille unhindered by necessary manual actions
5	R_004	The braille display contains 20 adjacent cells and weighs at most 1 kg	Most braille displays for smartphones are at most 20 cells, for the sake of portability we will adhere to 20 cells and a maximum of 1 kg as a template
6	R_005	When fully charged, the device can operate for at least one hour	Users have short reading sessions of approximately 30 minutes, for the sake of deviation it should operate for at least one hour.
7	R_006	The device has a USB connection with a computer	Allows user to upload pdf books to the device to be read.
8	R_007	The device has an on-board memory storage of at least 1 GB	It won't be necessary to tether the device and it can be used to read books on the go
9	R_008	The device is compatible for use with Windows 10 and newer operating systems	A majority of blind and visually-impaired people make use of Windows on their computers.
10	R_009	Only a palm rest surface is available underneath the braille display with no buttons	In order to avoid forcing users to keep their hands in the air while reading for comfort. Buttons in that position cause hand strain over long-term use.
11	R_010	Buttons have a soft pressure point and provide tactile contact feedback	The buttons should be pleasant to use as to let the user know when it has been successfully pressed without requiring a lot of force.
12	R_011	The bottom of the device has rubber feet	Avoid the device from shifting position when being read by the user.
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