Electronically‐controlled, portable, cone penetrometer1

Abstract

An electronically‐controlled, portable, cone penetrometer was designed, built, and tested. The penetrometer was driven electrically through a linear actuator. Cone position was sensed by a 10‐turn potentiometer, and force was sensed with an electronic load cell. A laptop computer controlled the linear actuator and recorded signals from the sensors through a data logger equipped with a serial interface. The penetrometer was capable of driving the cone at 0.84 cms‐1 (±5%) over a load range of 0 to 180 kg. The system allowed force and position excursion limits to be set through software and provided data sets at 1‐cm increments to depths of 45 cm and forces to 2,000 N. The penetrometer demonstrated good repeatability among closely spaced probings when force per unit cone area was plotted against depth.