Tactile guides for touch screen controls

Complex scientific and electronic measurement instruments often require precise adjustments which are typically accomplished with physical controls such as buttons, knobs, sliders and switches (for example see Figure 1). Users of modern test equipment are accustomed to these physical controls, which by learning and adaptation are perceived as natural and intuitive. More importantly, physical control surfaces allow for precise, intuitive manipulation while the operator’s vision is cognitively focused on the visual task at hand rather than on the control device. A typical example would be an oscilloscope user adjusting a wave form display via adjustment knobs. More commonly, anyone who has compared a physical versus an on-screen keyboard will quickly grasp the significant benefit of physical vs. virtual input devices for some tasks.