Melissa L. McGuire

Glenn Research Center, Cleveland, Ohio

Matthew R. Kunkel and David A. Smith

Wyle Information Systems, Cleveland, Ohio 

GLobal Integrated Design Environment (GLIDE): 

A Concurrent Engineering Application 

NASA/TM—2010-216909

December 2010
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Melissa L. McGuire

Glenn Research Center, Cleveland, Ohio

Matthew R. Kunkel and David A. Smith

Wyle Information Systems, Cleveland, Ohio 

GLobal Integrated Design Environment (GLIDE): 

A Concurrent Engineering Application 

NASA/TM—2010-216909

December 2010

National Aeronautics and

Space Administration

Glenn Research Center

Cleveland, Ohio 44135
Acknowledgments

The authors wish to express their deep thanks to Leon Gefert for creating GLIDE 1.0 in response to engineering analysis team 

need to transfer data in a clean and organized fashion. The authors also wish to thank Maria Babula, Branch Chief of the Mission 

Design and Analysis Branch, for supporting the development of GLIDE 2.0 and championing its use within GRC. Special thanks 

to Steven Oleson, the technical lead of the COMPASS team, for supporting the development of and use of GLIDE 2.0 in the 

ongoing studies of the COMPASS Team.

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Trade names and trademarks are used in this report for identifi cation 

only. Their usage does not constitute an offi cial endorsement, 

either expressed or implied, by the National Aeronautics and 

Space Administration.

Level of Review: This material has been technically reviewed by technical management. 

This report is a formal draft or working 

paper, intended to solicit comments and 

ideas from a technical peer group.
NASA/TM—2010-216909 1

GLobal Integrated Design Environment (GLIDE): 

A Concurrent Engineering Application 

Melissa L. McGuire

National Aeronautics and Space Administration

Glenn Research Center

Cleveland, Ohio 44135

Matthew R. Kunkel and David A. Smith

Wyle Information Systems

Cleveland, Ohio 44135

Abstract

The GLobal Integrated Design Environment (GLIDE) is a client-server software application purposebuilt to mitigate issues associated with real time data sharing in concurrent engineering environments and 

to facilitate discipline-to-discipline interaction between multiple engineers and researchers. GLIDE is 

implemented in multiple programming languages utilizing standardized web protocols to enable secure 

parameter data sharing between engineers and researchers across the Internet in closed and/or widely 

distributed working environments. A well defined, HyperText Transfer Protocol (HTTP) based 

Application Programming Interface (API) to the GLIDE client/server environment enables users to 

interact with GLIDE, and each other, within common and familiar tools. One such common tool, 

Microsoft Excel (Microsoft Corporation), paired with its add-in API for GLIDE, is discussed in this 

paper. The top-level examples given demonstrate how this interface improves the efficiency of the design 

process of a concurrent engineering study while reducing potential errors associated with manually 

sharing information between study participants.

Introduction

Concurrent engineering is a process that involves multiple engineers and/or researchers designing a 

product (Ref. 1 to 6). Concurrent engineering studies offer advantages over non-parallel engineering 

strategies in that every aspect of the overall product design is considered simultaneously. When done 

correctly, this simultaneous approach reduces overall product design time. Since numerous engineers are 

engaged in the design cycle at the same time, concurrent engineering fosters an overall collaborative 

development where multiple experts (or teams of experts) are focused on the same product at the same 

time. While concurrent engineering is a very useful technique when used properly, a central concern for 

the process is how key information and data are shared between participants in a design cycle. The issue 

is of central importance when data and calculations from one discipline are dependent on data and 

calculations from another discipline. Sharing data parameters and information between participations in a 

concurrent engineering process must be quick, reliable and often must be secure.

The GLobal Integrated Design (GLIDE), Figure 1, is a client/server/API engineering application 

designed to facilitate multi-discipline, concurrent engineering study sessions by providing a convenient, 

reliable, fast (near real-time) and secure environment for researchers and engineers to share data and the 

results of calculations with each other. GLIDE utilizes common web technologies (Apache, HTTP, php) 

for client-server interaction making it relatively easy to install, use and maintain. The API for GLIDE 

requires applications to pass data into the environment with HTTP “put” commands and receive data 

through HTTP “get” commands. Given the web server-like appearance for the API, GLIDE’s user 

interface is common, versatile and affords users the ability to interact with GLIDE through common front 

ends. GLIDE case studies in this paper focus on one particular API consisting of a Visual Basic for 

Applications (VBA) plug-in for Excel. This plug-in essentially makes Excel the user front end to GLIDE.
NASA/TM—2010-216909 2

Figure 1.—The GLIDE Logo and acronym.

The purpose of this paper is to introduce GLIDE as a concurrent engineering tool and to detail its 

technical composition. A brief history of GLIDE is presented as a motivation for the tool development.

Once introduced, case studies from real world studies using GLIDE at NASA Glenn Research Center 

(GRC) are presented to illustrate its usefulness and its user interface through Excel.

Nomenclature

API Application Programming Interface

APL Applied Physics Lab 

ARC NASA Ames Research Center

CAD computer aided design

COMPASS COncurrent Multidisciplinary Preliminary Assessment of Space Systems

DLL Dynamic Link Libraries

DOE Department of Energy

GLIDE GLobal Integrated Design Environment

GRC NASA Glenn Research Center

GSFC NASA Goddard Space Flight Center

GUI graphic user interface 

Gzip GNU zip

HTTP HyperText Transfer Protocol

ICP Intramural Call for Proposals

JPL NASA Jet Propulsion Laboratory 

JSC NASA Johnson Space Center

LAN local area network

LaRC NASA Langley Research Center

LSMD Laboratory for Spacecraft and Mission Design

MEL Master Equipment List

MySQL My Structure Query Language

NASA National Aeronautics and Space Administration

NEDT NASA Engineering Design Team

OS X Apple’s Operating System “X”

PHP Hypertext Preprocessor (originally personal home page)

SEP Solar Electric Propulsion 

SQL Structured Query Language

SSL secure sockets layer

TTPO Technology Transfer and Partnership Office 

VBA Visual Basic for Applications

VM virtual machine

XML Extensible Markup Language
NASA/TM—2010-216909 3

Background and GLIDE History

GLIDE was originally developed at GRC for the In-Space Propulsion program to support multicenter, 

multidiscipline studies.

In 2005, as part of an Intramural Call for Proposals (ICP)-award project, GRC participated with many 

NASA centers—including the NASA Ames Research Center (ARC), Goddard Space Flight Center

(GSFC), Jet Propulsion Laboratory (JPL), Johnson Space Center (JSC), and Langley Research Center

(LaRC)—and the Aerospace Corporation, an industry partner, to form the NASA Engineering Design 

Team (NEDT) to examine designs for the 2022 Mars Sample Return Mission (Refs. 7 and 8). As a 

concurrent study, NEDT was faced with the challenge of exchanging information in a near real-time. To 

solve NEDT’s issues with real-time information exchange, several existing technologies were 

investigated (including Modelcenter(Refs. 9 and 10) by Phoenix Integration, ICEMaker (Ref. 11 and 12) 

developed by LSMD). While these technologies were found to be useful, they were limited. After visiting 

Team X, JPL’s concurrent engineering team, and attempting to integrate the Team X tools into a

collaborative design team across the agency, the need for a tool that could operate both synchronously 

and asynchronously across firewalls was identified. Issues identified and solved using the GLIDE 

application were limited access due to firewalls (NASA, DOE, and other partners), lack of asynchronous 

data availability provided by tools available at the time, difficult NASA wide scalability, both cost and 

technological, cross platform (Macintosh (Apple, Inc.) and Microsoft Windows (Microsoft Corporation)) 

capability and ease of use for integration to current engineering tools.

To address these issues, a prototype for GLIDE was developed and used to share data directly from 

within Excel workbooks across disciplines. Figure 2 shows the infrastructure data flow and protocol used 

by the NEDT. GLIDE was selected and used as the preferred parameter-exchange solution by ARC, 

GRC, GSFC, and JSC. LaRC also demonstrated parameter exchange using GLIDE, but LaRC’s role 

within the Mars sample return study did not require parameter exchange. The green dotted lines show 

where the GLIDE application via HTTPS was used, and the red lines showed where the file sharing for 

data exchange methodology was used.

Figure 2.—The GLIDE Client-Server paradigm as applied to NEDT.
NASA/TM—2010-216909 4

Since its inception in 2005, GLIDE, and its Excel API interface have been refined and now function 

as the primary concurrent engineering application tool for the GRC concurrent engineering design team, 

Concurrent Multidisciplinary Preliminary Assessment of Space Systems (COMPASS). The COMPASS 

team typically designs complex aerospace systems requiring specific engineering expertise from multiple 

disciplines and operates in a fashion similar to JPL’s Team X (Ref. 13) or GSFCs IDC (Ref. 14). These 

disciplines, such as Avionics, Communications, Power, Propulsion, Structures, and Thermal are called 

upon in near real-time to contribute their expertise to size their subsystem. These subsystems are then tied 

together at the system integration level to build the entire system in answer to a customer request. Some 

of these customers include Exploration Systems Architecture Study designs for Ares V, In-space designs 

using electric propulsion thrusters, lunar communications satellites and ground assets, and recent studies 

for the committee conducting the Review of U.S. Human Space Flight Plans (aka Augustine Committee).

The COMPASS team has used GLIDE to pass data in order to enable fast, complex, concurrent design 

studies. The customer is often present during the design session. The interconnectedness of each 

discipline’s role to the overall system design results in an iterative concurrent engineering process.

What GLIDE Is

GLIDE is data exchange tool that works by populating a MySQL database through a publish and 

subscribe methodology. It is secure in that Data is sent via secure SSL encryption protocol, and as such is 

capable of securely crossing firewalls. It is capable of asynchronous and synchronous operation. GLIDE 

was designed to be a tool that includes engineers and analysts and their discipline tools in the design 

process. Because most engineering discipline experts are familiar with Excel, GLIDE uses Excel as a 

front end graphic user interface (GUI) to request/subscribe Name/Value pairs-based data in a database to 

facilitate an organized passing of data between disciplines. As an Excel aware application, GLIDE can 

take advantage of Solver in Excel or tailored optimization routines written in Visual Basic. It can also 

utilize Excel’s ability to import Dynamic Link Libraries (DLLs) or read in Fortran and C files (on both 

Macintosh and Microsoft Windows platforms) to tie data from text input/output files through GLIDE to 

the database for data transfer. It was written as a cross platform compatible application on both Windows 

and Macintosh OS X platforms. GLIDE enables the identification of data holes and the assignment of 

required data generation. Data can be generated with outside tools, codes, etc and fed back through 

GLIDE via the Excel interface or with cell-based arithmetic or VBA based analysis within Excel.

What GLIDE Is Not

GLIDE is not an analysis tool with any inherent analytical expressions or engineering optimization 

capabilities. It is not tied to any specific type of modeling or methodology, except the Master Equipment 

List (MEL) process used by COMPASS. GLIDE is not limited to types of systems in a design such a 

spacecraft or other space related designs such as done by the COMPASS team. GLIDE does not require 

additional software installation on most engineers’ machines, other than the client and Excel add-in, as 

most engineers have Microsoft products as part of the standard suite of tools installed on their computers. 

GLIDE does not have steep learning curve since most engineers are familiar with Excel.

GLIDE Technical Description

GLIDE is written as a compilation of several programming languages, including REALbasic 

developed by REAL Software, Inc. (Ref. 15), PHP (Ref. 16), and VBA. GLIDE client installers are 

available to download for both Microsoft Windows and Macintosh systems. The GLIDE client software is 

compatible with Excel 2000 or later on Windows systems and with Excel X and 2004 on Macintosh 

systems. Currently GLIDE is only available to users at GRC, where it is being beta tested, but is in the 

process for release through the GRC Technology Transfer and Partnership Office (TTPO).
NASA/TM—2010-216909 5

Figure 3.—The GLIDE Client-Server paradigm.

GLIDE follows the Client-Server paradigm as shown graphically in Figure 3, transferring encrypted 

and compressed data via standard web protocols. Currently, engineers use Excel as a front-end to the 

GLIDE Client as many of their custom tools run in Excel. As such, GLIDE is not a stand-alone 

engineering model but an interface to various subsystem engineering models, each of which is 

appropriately chosen on a case-by-case basis. Consequently, the inputs linked by GLIDE change with 

every design.

GLIDE Server

The GLIDE Server was designed to run on a standard web-server configuration, specifically: Linux, 

Apache (The Apache Software Foundation (Ref. 16)), MySQL (MySQL AB), and PHP. Both Linux and 

Apache are often utilized together to provide a reliable applications base. PHP: Hypertext Preprocessor, is 

an interpreted scripting language that operates well with MySQL, an open-source SQL database server.

On the GLIDE Server, PHP scripts handle all GLIDE Client communication, storing datasets in the 

MySQL database. A Jabber server is also part of the GLIDE Server’s configuration, which allows for the 

dynamic creation of chat rooms for each design session to facilitate the design process.

Server Background and Description

The GLIDE Server is based on Apache and uses PHP scripts to process requests from the Client. This 

design allows users to connect from any computer with Internet access, either directly or through a proxy.

The Client to Server protocol consists of HTTP-POST data sent over SSL. A POST message is a type of 

HTTP request message. The Server responds with GZip compressed data wrapped in Extensible Markup 

Language (XML). The parameter datasets are formatted in new-line separated rows of tab-delimited 

fields, a format chosen for its low overhead and native compatibility with Excel. The Server generates the 

returned dataset using the most recently submitted set of values, however, all values submitted are 

retained, thereby providing version support. The ability to revert to a previous point can save time in a 

design session in which the dataset diverges continually and the final answer is not reaching convergence.

The engineering lead can decide to choose a different dataset of trade space iteration in order to converge 

on a closed solution to the design problem. It also allows for spin-off studies based on previous work to 

be started very quickly, in as short as minutes.

The Server Side API has been written such that any application capable of submitting HTTP Forms 

using POST variables over SSL, which is also able to unzip and parse XML, can be configured to act as a 

GLIDE Client with a minimum amount of programming required. In the event that an application is not 

capable of the encryption, decompression, or XML parsing requirements, that application might still be 

able to connect to the server via the Client Side API. Figure 4 shows the server and client API concept in 

graphical representation, highlighting the ability for the GLIDE client data transfer to pass securely 

through firewalls.
NASA/TM—2010-216909 6

Figure 4.—GLIDE server and client API illustration.

GLIDE Client

The GLIDE Client was implemented in REALBasic to provide support for Windows, OS X, and Linux 

through the compilation of platform-specific binaries from a universal set of source code. The GLIDE Client 

Tool is a client side application with the primary job of acting as data conduit between the GLIDE server 

and GLIDE enabled Excel workbooks. The Client tool performs this job by providing: user authentication, 

data publishing, and data subscribing and available data queries. Additional services provided by the Client 

Tool include: data management, reporting queries history of datasets, and data age reporting. In addition to 

passing engineering datasets between the GLIDE Server and the Front-End, the Client also incorporates a 

proprietary Jabber client and other tools to view design session information and status.

Tracking Progress With the Client

A data progress graph can be defined on a per-session basis to enable real-time auditing or tracking of 

key system parameters from within the Client application window. Custom graphs can be created, as 

shown in Figure 5, to track changes in one or more system parameters. There is also the beta testing of an 

internal to the client file sharing mechanism to allow for file transfers to and from the Server without 

having to allow for WebDAV mounted shares on the server itself. This method will allow for more secure 

transfer of files across a network and across firewalls. The client provides additional monitoring of the 

dataset information, such as, data age and user activity. This functionality enables the iterative process to 

continue, in the case where not all participants are located in the same facility. Authentication to the 

Server is handled from the Client via an SSL socket over which all data is transferred.

Client Window Display

The Client maintains responsibility for all server communication including encryption, 

decompression, and XML parsing. Excel, or any front-end, must configure design session specific 

settings and then can make standard HTTP GET requests to the Client’s internal web-server. The Client 

Side API has been written to allow Excel to send and receive data as efficiently as possible; Excel Macros 

running VBScript are sometimes slow in execution time. This implementation gives Excel the ability to 

use the built-in External Data tool to perform a Web Query and insert the returned data directly into cells 

on a spreadsheet. The Server responds with the data format that Excel expects, thereby eliminating any 

need for dataset processing on the Excel side. Figure 6 shows some of the data available via the GLIDE 

Client window. In this case, the user can see which parameters have been input and by which users, as 

well as additional data about those parameters. As the GLIDE Client evolved based on user requests, 

additional information has and will be incorporated.
NASA/TM—2010-216909 7

Figure 5.—GLIDE Client Data Tracking Custom Graph Function example.

Figure 6.—GLIDE Client Window Display example.
NASA/TM—2010-216909 8

GLIDE and Its Use in the Design Process

Generally, a concurrent design session consists of two or more engineers representing each discipline 

meeting together in a single location, or remotely in separate locations via teleconference interface. The 

lead discipline engineers exchange parameters and iterate through their respective processes to converge 

on an acceptable dataset. In cases in which the engineers are unable to meet, their parameters are passed 

via email, telephone, facsimile, or even postal mail. The result of this slow process of data exchange 

would elongate a design session to weeks or even months. Often one subsystem provides designs based 

on out-dated information on the other subsystems.

With the rise of ubiquitous Internet access, it is a logical step forward to utilize technology to realtime and streamline this process. While the iterative process remains in place, software can now exchange 

parameters securely and efficiently, while at the same time allowing for much more information about a 

design session to be made available.

Most Engineers are familiar with and have detailed top-level design tools created in Microsoft’s 

Excel application. In addition, since Excel is available on both the Windows and Macintosh platform, 

rather than recreate the front end GUI with which to view the data to be passed, the developers decided to 

build an interface between the GLIDE server and GLIDE database and Excel. This involved the creation 

of an Excel add-in. Figure 7 illustrates how the COMPASS concurrent engineering design team currently 

uses the GLIDE server, the GLIDE client, and the GLIDE WebDAV shares in study sessions. The 

GLIDE server uses a virtual machine (VM) set up to allow for WebDAV shares on one VM and the 

database on a second VM. The GLIDE client tool and GLIDE enabled Excel workbooks on the user’s 

computer interface with this server.

A typical design session uses the GLIDE application to tie together various subsystem engineering 

experts. In a COMPASS session, those experts include Propulsion systems, power system, 

communications systems, structures and mechanisms, Thermal protection and avionics systems engineers 

as well as trajectory and other mission analysis experts. This iterative and concurrent engineering 

relationship is shown in Figure 8. The subsystem leads use the GLIDE application and framework to tie 

together their analysis of a single design. The system integration lead engineer iterates with that data until 

a design has reached closure (for example, propellant tanks are sized to hold propellant necessary to 

perform a mission) during an iteration loop.

Figure 7.—GLIDE Server, Client, and Share structure.
NASA/TM—2010-216909 9

Figure 8.—COMPASS team structure and GLIDE application usage.

Figure 9.—GLIDE application Microsoft Excel toolbar.

Microsoft Excel Add-In

Most users prefer to use software with which they are already familiar to participate in GLIDE design 

sessions. For this reason, the current front-end to GLIDE is Excel with the help of an add-in. Once the 

add-in has been installed to the user’s Excel application, the toolbar and its functionality will become 

available. The toolbar, shown in Figure 9, provides GLIDE’s core functionality to Excel: the ability for 

the user to view parameters, send output, and refresh input.

Upon a user’s request to view available parameters in Excel, the add-in requests data from the Client, 

the Client then requests the data from the Server, and responds to the Excel add-in with the result returned 

from the Server. Custom Application Programming Interfaces between both the Front-End and the Client, 

and the Client and the Server, allow integration to other engineering applications as needed. The FrontEnd API can be implemented in an application without the need to account for authentication to the server 

or the ability to decrypt or decompress the data received from the Server.

Parameter Inputs and Outputs

GLIDE-ifying an Excel workbook adds in five additional worksheets to the workbook: Available, 

Unavailable, Inputs, Outputs and Aliases. The two worksheets that will be used most often by the 

engineer to transfer and receive data are the Inputs and Ouputs sheets. As should be obvious, the Inputs 

tab (sheet as shown in Fig. 10) is a worksheet set up to gather all of the variable names for which the 

engineer needs the associated data. The Outputs tab (or sheet) is where the discipline engineer places the 

variables for which they are publishing the associated values.

Integration

Mission

Analysis Study

Manager

Payload

Results,

Documentation

Structures

& Mech.

Avionics

Thermal

Propulsion

Power

Comm

GLIDE
NASA/TM—2010-216909 10

Figure 10.—GLIDE-ified Microsoft Excel workbook input sheet.

Example Case Study: Mercury SEP Stage

At the time of the writing of this paper, the COMPASS team is currently designing a Solar Electric 

Propulsion (SEP) stage to send a yet to be designed Lander to Mercury as part of the Decadal survey 

planning done by NASA’s Science Mission Directorate. The COMPASS design team consists of 

engineers from multiple disciplines (Power, Propulsion, Mission design, Thermal, Communications, 

computer aided design (CAD), etc) and organization codes across GRC. The team members meet in the 

COMPASS lab during the thrice-weekly study sessions, or tie in from remote locations via a 

teleconference number. The GLIDE application allows the engineers to publish and subscribe to the data 

from their desks. Even though they cannot be present, the portable and cross-internet nature of GLIDE 

allows engineers to actively participate in a live design session.

The ACE lab at the Applied Physics Lab (APL) (Ref. 17) is designing the Lander. The APL and 

COMPASS teams are interfacing their two designs via the sharing of requirements; design decisions and 

top level Master Equipment Lists (MELs) generated using file exchange, teleconferences and 

videoconferences. It is planned in the future to link the two teams together through the use of the GLIDE 

application and sever in order to provide an end-to-end design in real time from two physically separate 

engineering design teams.

A past example of a COMPASS design, which used the GLIDE server and client, is documented in 

Reference 18 and involved the design of a Near Earth Asteroid sample return spacecraft. The customer 

brought the requirements of the study, and the COMPASS team tied together the relevant discipline leads 

via a MEL interface built in Excel to design the spacecraft. This design and the flexibility of GLIDE was 

used to allow the team to perform trades through multiple cases in which different propulsion system 

options were tested and compared.

Other Uses of the GLIDE Application

Other potential users of the GLIDE application are any concurrent design engineering or other 

similar entity, which would have the need to link together, multiple mathematical or logical data sets

(Ref. 19). There are a number of concurrent engineering teams like COMPASS at NASA and any one of 

them could apply the GLIDE model to data passing (GSFC IDC (Ref. 14), Team X (Ref. 13), LaRC IDC 

(Refs. 20 to 22)). GLIDE could easily be integrated either inside the current operating practices of these 
NASA/TM—2010-216909 11

teams or be used to link the teams remotely to perform concurrent engineering design sessions across 

these multiple centers.

Up to now, GLIDE has been used within the framework of designing a spacecraft or other space 

related system. While this has proven a very efficient way to pass data for the spacecraft design teams, 

there is no reason that the data has to be spacecraft in nature. GLIDE could pass any data that is set up 

using a parameter/value methodology. Current applications under study include automation of 

management practices and automation of detailed communications system design.

Limitations of the Current GLIDE API

The current API used for GLIDE is Excel and therefore any and all limitations inherent in Excel also 

limit the client side usage of GLIDE. One limitation on the transfer of data is also tied to Excels use of a 

255 characters per cell limit, as well as limit in number of lines and columns that Excel can handle in any 

workbook. In addition, as Microsoft changes versions of Excel, the add-ins and formatting of the Excel 

connection to GLIDE have to be revisited. The GLIDE developers have to be cognizant of how changes 

in the VBA implementation will affect the ability of the GLIDE add-in to perform its functions. Recently, 

Microsoft has dropped support of Virtual Basic in the Macintosh OS X version of Excel 2008, and has no 

official plans to replace it. For this reason, all Macintosh users have to continue to use either Office X or 

2004 in order to run GLIDE. Future versions of GLIDE will continue to support both the Macintosh and 

the Windows platforms, so work is ongoing to find a workaround for the Excel add-in API on the 

Macintosh solution.

Since GLIDE was written as a parameter passing solution, it is also not suited to the transfer of files 

such as CAD or other engineering files. It could be used to pass data about those files but not the files 

themselves. There are no plans to change GLIDE into a file passing application at this time.

Conclusion

The ability of GLIDE to tie together multiple participants who are both collocated and/or dispersed in 

remote duty stations, has given the COMPASS team the ability to quickly perform designs of relatively 

complex space systems. Removing potential human error in data passing by automating the process has 

increased the reliability and accuracy of the data produced in the COMPASS design sessions. Without the 

GLIDE application, these design sessions would take much more time making multiple trade space 

iterations impossible in the limited amount of time currently allocated to such tasks.

GLIDE uses a common Web-based MySQL server that is accessed using PHP scripts (the PHP 

Group). MySQL is a relational database management system, available as an open source system.

GLIDE’s Web-served database allows secure and controlled access to design data by using firewallfriendly secure sockets-layer- (SSL-) based user authentication. Data can be queried and published to the 

GLIDE database via a Excel interface. The training of GLIDE users is relatively effortless since most are 

familiar with Excel.

Availability: The GLIDE development team is currently working with the GRC TTPO to release 

GLIDE to other government and academic institutions. It is hoped that this process will be completed in 

the near future.

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10. Taylor, J.L.; Neely, M.A.; Curran, F.M.; Christensen, E.R.; Escher, D.; Lovell, N.; Morris, Charles

(Technical Monitor), “Integrated Technology Assessment Center (ITAC) Update,” AIAA–2002–

3550, 8th AIAA/ASME/SAE/ASEE Joint Propulsion Conference; Jul. 7–10, 2002; Indianapolis, IN.

11. LSMD (Laboratory for Spacecraft and Mission Design): ICEMaker, 

http://www.lsmd.caltech.edu/tools/icemaker/icemaker.php.

12. Schuman, Todd; de Weck, Olivier, L.; Sobieski, Jaroslaw: “Integrated System-Level Optimization for 

Concurrent Engineering with Parametric Subsystem Modeling,” 46th AIAA/ASME/ASCE/AHS/ASC 

Structures, Structural Dynamics and Materials Conference; Apr. 18–21, 2005; Austin, TX.

13. Jet Propulsion Laboratory Team X homepage: http://jplteamx.jpl.nasa.gov/.

14. NASA Goddard Spaceflight Center Integrated Design Center homepage: http://idc.nasa.gov/.

15. REALBasic software: http://www.realsoftware.com/realbasic/.

16. PHP reference: http://en.wikipedia.org/wiki/PHP.

17. The Apache Software Foundation: http://www.apache.org/.

18. The Johns Hopkins University Applied Physics Laboratory: http://www.jhuapl.edu/.

19. Oleson, Steven R.; and McGuire, Melissa L., “COMPASS Final Report: Near Earth Asteroids 

Rendezvous and Sample Earth Returns (NEARER),” NASA/TM—2009-215825; CD–2008–28.

20. GLIDE software release website: http://www.grc.nasa.gov/WWW/RT/2005/PB/PBM-gefert.html.

21. NASA Langley Research Center Integrated Design Center homepage. http://idc.larc.nasa.gov/.

22. Gough, Kerry M., Allen, B. Danette; and Amundsen, Ruth M.: “Collaborative Mission Design at 

NASA Langley Research Center,” GT–SSEC.A.3.
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GLobal Integrated Design Environment (GLIDE): A Concurrent Engineering Application 

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14. ABSTRACT

The GLobal Integrated Design Environment (GLIDE) is a client-server software application purpose-built to mitigate issues associated with 

real time data sharing in concurrent engineering environments and to facilitate discipline-to-discipline interaction between multiple 

engineers and researchers. GLIDE is implemented in multiple programming languages utilizing standardized web protocols to enable secure 

parameter data sharing between engineers and researchers across the Internet in closed and/or widely distributed working environments. A 

well defined, HyperText Transfer Protocol (HTTP) based Application Programming Interface (API) to the GLIDE client/server environment 

enables users to interact with GLIDE, and each other, within common and familiar tools. One such common tool, Microsoft Excel 

(Microsoft Corporation), paired with its add-in API for GLIDE, is discussed in this paper. The top-level examples given demonstrate how 

this interface improves the efficiency of the design process of a concurrent engineering study while reducing potential errors associated with 

manually sharing information between study participants.

15. SUBJECT TERMS

Concurrent engineering; Real-time operation; Programming language; Application programming interface 

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