TESTING AND EVALUATION OF ROADBOUNCE - MOBILE PHONE APP BASED TECHNOLOGY FOR ROAD ROUGHNESS MEASUREMENT.

Road Roughness/Unevenness is an important parameter for the evaluation of the surface condition of a road. Roughness affects the vehicle operating cost, speed, riding comfort, safety, fuel consumption, and tire wear and tear. Every road user desires to have a smooth and comfortable riding. Roughness measurement is an important activity on highways based on which maintenance decisions are taken. IRC (Indian Road Congress) manual specifies roughness measurements to be taken at every 6 months on highways and based on the roughness index the functional overlay requirements are decided on highways. Roughness measurements using profilometers, namely Rod and Level, Dipstick, Merlin, Profiler, LiDAR, etc., give detailed surface profile measurements but are time-consuming. An alternative to profilometers is Response Type Road Roughness Measurement Systems (RTRRMS) which are installed on vehicles and measure how the vehicle responds to the pavement profile. A car-mounted fifth wheel Bump Integrator developed by CRRI in India is commonly used to measure roughness. The fifth wheel bump integrator system works through mechanical instruments producing 'bumps,' a binary, 'true or false' information, instead of 'range based' analog information produced by digital accelerometers commonly found in smartphones. Due to the difficulty in the calibration process, towing for longer distances, and complexity in recording, analyzing, and possible manual errors in recording the data, Cell Phone-based systems are becoming popular for their simplicity in measuring roughness using accelerometers embedded in the cell phone. RoadBounce is one such technology using Cell phone-based mobile Apps to measure roughness. This paper intends to present the findings of testing and evaluation of App-based roughness measurement technology for its accuracy and usability using different vehicles and mobile phones under different speeds, tire pressures, gradients, etc. [ABSTRACT FROM AUTHOR]