We report on the Latency Hammer, a low-cost yet highaccuracy and high-precision automated tool that measures the interface latency of touchscreen devices. The Hammer directly measures latency by triggering a capacitive touch event on a device using an electrically actuated touch simulator, and a photo sensor to monitor the screen for a visual response. This allows us to measure the full end-toend latency of a touchscreen system exactly as it would be experienced by a user. The Hammer does not require human interaction to perform a measurement, enabling the acquisition of large datasets. We present the operating principles of the Hammer, and discuss its design and construction; full design documents are available online. We also present a series of tools and equipment that were built to assess and validate the performance of the Hammer, and demonstrate that it provides reliable latency measurements.
['Jonathan Deber', 'Bruno Rodrigues De Araújo', 'Ricardo Jota', 'Clifton Forlines', 'Darren Leigh', 'Steven Sanders', 'Daniel Wigdor']
Hammer Time!: A Low-Cost, High Precision, High Accuracy Tool to Measure the Latency of Touchscreen Devices