Investigation of Potential Impact Parameters for Detection of Kopyor Coconut with Drop Test Method

Kopyor coconut is a mature coconut with distinct characteristics as compared to a normal coconut; it has a sweeter flavor and jelly-like meat texture resulting from genetic abnormalities. From its external appearance, kopyor coconut does not differ much from normal coconut, therefore a reliable detection method is necessary. The most common one to this day, practiced by farmers, are by shaking and knocking the coconut to obtain sounds that are unique to both coconuts. However, apparently this traditional method still results in false detections. In this research, detection of kopyor coconut by impact drop test is proposed. As a preliminary step, the aim is to investigate which impact parameters (impulse, peak force, and contact time) are unaffected by variation in coconut's mass. Additionally, the effect of variation in drop height is also investigated. Coconuts with three variations in mass (1.00 kg, 1.15 kg, and 1.30 kg) are used and dropped from three variations in drop height (0.3 m, 0.4 m, 0.5 m). The results show that mass variation affects impulse and peak force whereas drop height variation affects all impact parameters. Furthermore, impulse and peak force obtained are divided by corresponding coconut's mass and are observed. It has been shown that the impulse divided by the mass or contact time could be used as a potential parameter for detection. Moreover, since the variation in drop height affects all impact parameters, the drop test is suggested to be conducted at a fixed drop height.