The dynamic behaviour of cricket balls during impact and variations due to grass and soil type

Stroboscopic photography was used to analyse the impact of cricket balls on experimental plots constructed using different soil and grass types. All impacts were carried out using the same initial dynamic conditions, designed to simulate fast–medium bowling. Significant differences in the impact behaviour were found between both the grasses and soils and simulated trajectory analysis showed that soil choice (within the set of seven soils used) had a greater overall effect than grass choice (within the set of 10 perennial ryegrass cultivars used). Correlations between the dynamic data, pitch measurements and soil characteristics were examined and it was found that a damp, soft pitch (such as Mendip Loam, with a high organic matter content) leads to a low rebound velocity with high top spin, whereas a firm, dry pitch (such as Kaloam, with a low organic matter content) leads to a high rebound velocity with low top spin. The factors concerning rebound angle were found to be more complicated. A hypothesis was made that this was due to the combined effect of restitution and deformation on the rebound angle.