Methods for Mapping of Surface Charge Density on Arbitrary Dielectric Objects

A system to map surface charge densities on dielectric objects – e.g. PTFE, PMMA, and PA6 – is described to study maximum surface charge limits discharge and decay characteristics. Two electromechanical movements are used to achieve these goals: a three-axis robotic arm with an electrostatic probe and a three-axis auxiliary movement fitted with a current viewing resistor and laser displacement sensor. Dielectric objects no larger than a cylinder of eight-inch diameter and twelve inches in height are analyzed to create surface point clouds and generate a set of scan points. The arbitrary object is positioned upon a rotational axis with a laser displacement sensor oriented radially towards the rotational axis of the platform to determine the object’s physical limits.

I. Introduction

The focus of this study is to map the surface charge density of the surface of an object which is captured via a custom high-potential capable electrostatic probe and explores new methods of mapping surfaces while expanding on the reliance of electromechanical systems to provide faster and more concise results[1][2]. A system was created to measure the charge decay on objects surfaces in a low humidity environment over extended periods of time. A custom environmental chamber was created to accurately control humidity as closely as possible over the scan duration. An efficient algorithm is fundamental in hastening the pre-processing time for optimal pathing of the charge decay measurement duration while incorporating the other electromechanical systems.