Figure 2. Schematic of various in test method

1. continuous penetration at 2 cm/s
2. cycling at 2 cm/s
3. twitch test with consecutively halved penetration rate.

Cyclic tests consist of cycling the probe typically ten times over a 1 meter interval. Twitch tests consists of displacing the probe continuously, but reducing the penetration rate each time the probe has advanced three diameters.