The invention provides a device for measuring the dynamic coefficient of friction of a surface. The device includes a track having an arcuate portion which is shaped to mimic an arc of travel of a pendulum; a shoe mounted so as to be movable along the track, and a biasing device for biasing part of the shoe into contact with the surface as it moves along the arcuate portion of the track; a propulsion device for providing an initial propulsion force to propel the shoe along the track; a velocity detector for measuring the velocity of the shoe at a plurality of points during its travel along the track; and computing device for calculating the coefficient of friction from changes in velocity of the shoe as it moves along the track.