ASTM E2938-15(2023) PDF

SIGNIFICANCE AND USE 4.1 This standard provides a test method for obtaining the range error for medium-range 3D imaging systems. The results from this test method may be used to evaluate or to verify the range measurement performance of medium-range 3D imaging systems. The results from this test method may also be used to compare performance among different instruments. 4.2 The range performance of the IUT obtained by the application of this test method may be different from the range performance of the IUT under some real-world conditions. For example, object geometry, texture, temperature and reflectance as well as vibrations, particulate matter, thermal gradients, ambient lighting, and wind in the environment will affect the range performance. 4.3 The test may be carried out for instrument acceptance, warranty or contractual purposes by mutual agreement between the manufacturer and the user. The IUT is tested in accordance with manufacturer-supplied specifications, rated conditions, and technical documentation. This test may be repeated for any target 2 range within the manufacturer’s specifications and for any rated conditions. 4.4 For the purposes of understanding the behavior of the IUT and without warranty implications, this test may be modified as necessary to characterize the range measurement performance of the IUT outside the manufacturer’s rated conditions, but within the manufacturer’s limiting conditions. 4.5 The manufacturer may provide different values for the specifications for different sets of rated conditions, for example, better range measurement performance might be specified under a set of more restrictively rated environmental conditions. The user is advised that the IUT’s performance may differ significantly in other modes of operation or outside the rated conditions and should inquire with the manufacturer for specifications of the mode that best represents the planned usage. If a target other than that described in Section 7, or if procedures other... SCOPE 1.1 This standard describes a quantitative test method for evaluating the range measurement performance of laser-based, scanning, time-of-flight, 3D imaging systems in the medium range. The term “medium range” refers to systems that are capable of operating within at least a portion of ranges from 2 to 150 m. The term “time-of-flight systems” includes phase-based, pulsed, and chirped systems. The word “standard” in this document refers to a documentary standard as per Terminology E284. This test method only applies to 3D imaging systems that are capable of producing a point cloud representation of a measured target. 1.1.1 As defined in Terminology E2544, a range is the distance measured from the origin of a 3D imaging system to a point in space. This range is often referred to as an absolute range. However, since the origin of many 3D imaging systems is either unknown or not readily measurable, a test method for absolute range performance is not feasible for these systems. Therefore, in this test method, the range is taken to be the distance between two points in space on a line that passes through the origin of the 3D imaging system. Although the error in the calculated distance between these two points is a relative-range error, in this test method when the term range error is used it refers to the relative-range error. This test method cannot be used to quantify the constant offset error component of the range error. 1.1.2 This test method recommends that the first point be at the manufacturer-specified target 1 range and requires that the second target be on the same side of the instrument under test (IUT) as the first target. Specification of target 1 range by the manufacturer minimizes the contribution to the relative range measurement error from the target 1 range measurement. 1.1.3 This test method may be used once to evaluate the IUT for a given set of conditions or it may be used multiple times to bett...