Strapdown Associates, Inc.

4727 South Lake Sarah Drive

 Maple Plain, Minnesota 55359

 Phone:  (763) 479-1981     Ground Line Fax:  (763) 479-1476


Paul G. Savage - President  - Resume Professional ActivitiesPublications Through June 2016

Strapdown Associates, Inc. (SAI) is an independent Minnesota corporation founded in 1980.  SAI provides engineering consulting and educational services to aerospace companies and government agencies for design and test of aided and unaided strapdown inertial navigation systems

Website Contents

Paul G. Savage Books In Stock

Strapdown Inertial Navigation On-Site Courses

Paul G. Savage Free-Access Articles

Strapdown Humor

Note: Some of the files linked from this web are in .pdf format.  Translating the files requires Adobe Acrobat Reader which can be downloaded for free from the following website:

Books In Stock:  Strapdown Analytics II  &  Intro-To-Strapdown-Nav Course Books

Special Note On Ordering Books By Telephone !!

STRAPDOWN ANALYTICS II (Brochure With Ordering Info)  - In stock only at SAI.  The second edition of Strapdown Analytics, Paul G Savage's 1,646 page two volume hard cloth cover text is in stock now and available for purchase.  The book is a detailed comprehensive tutorial of the author's knowledge in all analytical aspects of unaided and Kalman filter aided strapdown inertial navigation.  This includes not only the algorithms implemented in the strapdown system computer, but the analytics associated with system validation, test, simulation, and performance analysis.  Equations are derived from basics including intermediate steps, avoiding the common practice of referencing supporting equations to other source material.  This is not a simple book, covering some complicated analytical subjects.  Nevertheless, it has been designed for engineering analysts or graduate students having only a basic working knowledge of vector calculus and matrix operations.  Previous background in inertial navigation or navigation in general is not required.  Strapdown Analytics II - Table of Contents, Chapter 1 - Introduction

Errata For Strapdown Analytics I

Errata For Strapdown Analytics II Through March 2017

 Intro-TO-STRAPDOWN-NAV Course Books (brochure With Ordering Info) - In stock only at SAI.  From 1981 to 2009, SAI provided its four and a half day Introductory Course On Strapdown Inertial Navigation Systems to the general public in Minneapolis-Minnesota and on-site at contracting host facilities.  The Introduction-To-Strapdown Inertial Navigation and Strapdown Inertial Navigation Lecture Notes books used in the course and prepared by the course instructor Paul G Savage, are in stock now only at SAI, and available for purchase:

Introduction To Strapdown Inertial Navigation Systems - 712 page "Yellow Book" containing the Introductory course presentation slides with accompanying detailed text descriptions.

Strapdown Inertial Navigation Lecture Notes - 376 page reformatted "Blue Book" providing descriptions of strapdown inertial sensors and derivations of key equations presented in the course.

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On-Site Strapdown Inertial Navigation Courses

 SAI offers a Two-Day On-Site Introductory Strapdown Inertial Navigation Systems Course for interested organizations at the host selected site location in the contiguous United States and Canada.  This is a shortened version of the original four and a half day Introductory Course offered by SAI in Minneapolis, Minnesota from 1982 - 2009.  As with the original course, the Short Course is designed for engineering, management and marketing personnel who have a fundamental background in engineering, but no former background in inertial navigation or complex mathematics.  The slides used in the two-day course are the same primary slides used in the original 4 1/2 day course as contained in the presentation book for both courses - Introduction To Strapdown Inertial Navigation Systems by Paul G. Savage, the instructor for the Original Course and for the Short Course.

Applied Strapdown Analytics (ASA) offers a  4 1/2 Day On-Site Advanced Strapdown Analytics Course that rigorously focuses on the detailed analytical aspects of strapdown inertial navigation.  The advanced course is provided by Paul G Savage's daughter Kelly Roscoe, Owner of ASA.  The analytical basis for the course is the book Strapdown Analytics II provided as one of the advanced course handouts.  The advanced course can be viewed as a quick and easy way to obtain and learn the material presented in the detailed and lengthy Strapdown Analytics II.

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Paul G. Savage Free-Access Technical Articles Available At This Website

Previously Published Articles Formatted For Web Access

"Performance Analysis Of Strapdown Systems", SAI-WBN-14011, June 2, 2015

"Computational Elements For Strapdown Systems", SAI-WBN-14010, May 31, 2015

"Blazing Gyros - The Evolution Of Strapdown Inertial Navigation Technology For Aircraft", SAI-WBN-14009, May 29, 2015

 Free Access Articles Prepared For This Website - Although every effort has been made to eliminate errors in the following Free Access articles, it is inevitable that some errors will pass undetected.  If readers plan to use the technical material for engineering projects, they are encouraged to re-verify the material by analytical means and simulation.

"Digital Integration Algorithm Error For Random Process Inputs", SAI-WBN-14018, June 26, 2016

"Skewed Sensor Failure Detection Using Parallel Navigation Solutions", SAI-WBN-14017, June 16, 2016

"Introduction To The Kinematics of Point-To-Point Relativity", SAI-WBN-14015, April 17, 2016 (Updated 05/02/16)

"Designing An Extended Kalman Filter For A Stellar Aided Strapdown Inertial Attitude Reference", SAI-WBN-14012, January 16, 2016

"Lever Arm Corrections During INS Transfer Alignment With Wide Angle Initial Heading Error", SAI-WBN-14008, April 17, 2015 (Updated 09/05/16)

"Coarse Leveling Of INS Attitude Under Dynamic Trajectory Conditions", SAI-WBN-14007, January 29, 2015

 "Moving Base INS Alignment With Large Initial Heading Error", SAI-WBN-14006, October 3, 2014

"Modifying The Kalman Filter Measurement To Mitigate Second Order Amplification In INS Velocity Matching Alignment Applications", SAI-WBN-14005, July 15, 2014

"Fixed Gain Digital Filter Design For Specified Phase Versus Frequency Response", SAI-WBN-14004, June 29, 2014

"Schuler Oscillations", SAI-WBN-14003, June 27, 2014

"Redefining Gravity And Newtonian Natural Motion", SAI-WBN-14002, May 21, 2014

"Mitigating Second Order Error Effects In Linear Kalman Filters Using Adaptive Process And Measurement Noise", SAI-WBN-14001, May 16, 2014

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Strapdown Humor

"Blazing Gyros - The Movie (Early Preview)", SAI-WBN-14016, May 25, 2016

"Geordie's Quaternion Decision", SAI-WBN-14014, February 17, 2016

"Program Management", SAI-WBN-14013, January 18, 2016

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