Johnson E L
J Med Syst. 1986 Jun;10(3):277-88. doi: 10.1007/BF00992823.
A keyboard has been designed and constructed for persons restricted to using a head or mouth stick. The keyboard is not a modification of existing keyboard technology but involves a completely new concept. The keyboard, called a 2DOF keyboard, requires only two degrees of freedom motion for actuation. The problems of simultaneous key requirements, accidental key strikes, and multiple strikes of the same key have been solved. The keyboard is transparent to the personal computer to which it is connected, allowing use of any available software.
已经为只能使用头部或口棒的人设计并制造了一种键盘。该键盘并非对现有键盘技术的改进，而是涉及一个全新的概念。这种被称为2自由度键盘的键盘，仅需两个自由度的运动来进行操作。同时按键需求、意外按键以及同一按键的多次敲击等问题已得到解决。该键盘对于其所连接的个人计算机是透明的，允许使用任何可用软件。
