CUBIC - A Digital Program for On-Line Differentiation of

8-559

Sample Analog Signals

John H. J. Allum, Man-Vehicle Laboratory, Massachusetts

Institute of Technology, Cambridge, Massachusetts

A digital computer program CUBIC has been developed for on-

line differentiation of analog voltage signals. The program

accepts voltage records of a time function and yields its

derivative after one program cycle time of 4.2 msecs. The

velocity is obtained by employing a least mean squares cubic

fit technique.

The routine is intended for experimental work either as a data

reduction tool or as a control signal for a closed loop experi-

ment. The program can be implemented on a PDP-8 digital

computer with one digital to analog converter channel and

one analog to digital converter channel.

Minimum Hardware:
PDP-8, 1 A/D and 1 D/A channel

Storage Requirement:
2K

Miscellaneous:
This work was supported in part by

NASA Grant NGR-22-009-025

Source Language:
PAL

Catalog: July 1973

Minimum Hardware:	PDP-8, 1 A/D and 1 D/A channel
Storage Requirement:	2K
Miscellaneous:	This work was supported in part by NASA Grant NGR-22-009-025
Source Language:	PAL
Catalog:	July 1973