GraphSTEP: concurrent, cloud-based, lifecycle-oriented editing and updating of product data

Keno Moenck · Adrian Pustelnik · Julian Koch · Thorsten Schüppstuhl
Hamburg University of Technology, Institute of Aircraft Production Technology

🧾 10.1016/j.procir.2023.09.058

The STEP standard is a file-/text-based format that is widely used in industry to store product-related data. GraphSTEP transforms STEP-modeled, more specifically, EXPRESS-modeled data, into a graph and feeds Neo4j to allow cloud-based data manipulation. GraphSTEP supports the following features

• Transforming a STEP file to a graph
• Transforming the graph back to a STEP file
• Manipulation operations (currently implemented: changing the pose of a part / adding new parts)
• Filtering operations (individual branches belonging to basic geometric components or full boundary representations)
• Version control system for STEP-based data
• Access to STEP attributes of all entities

In a nutshell, it brings your STEP files into the cloud and lets you do operations on it.

🏗 Getting Started

Initialize and build external dependencies:

git submodule update --recursive --init
./build.sh

Build GraphSTEP:

mkdir build
cd build
cmake ..
make GraphSTEP -j$(nproc)

Export as native add-on

GraphSTEP contains bindings to Node.js, such that you can use it, e.g., in your Express.js application:

npm ci
npm run build

Neo4j

Docker command to launch Neo4j instance (NEO4J_AUTH=neo4j/testpassword):

docker run --name neo4j -p7474:7474 -p7687:7687 \
  -d \
  -v $HOME/neo4j/data:/data \
  -v $HOME/neo4j/logs:/logs \
  -v $HOME/neo4j/conf:/conf \
  -v $HOME/neo4j/import:/var/lib/neo4j/import \
  -v $HOME/neo4j/plugins:/plugins \
  --env NEO4J_AUTH=neo4j/testpassword \
  --pull=always \
  --env NEO4J_ACCEPT_LICENSE_AGREEMENT=yes \
  neo4j:enterprise

Neo4j preparations

GraphSTEP (in its current configuration) uses three different graphs to store data:

Name	Description
productgraph	working graph, stores the STEP-modeled data of the product
macro	stores filtered graph components
history	stores the version history of the product data

Create these graphs, e.g., through Neo4j's web console:

create database productgraph
create database macro
create database history

🌟 Usage

Command Line Interface (CLI)

The functionalities of GraphSTEP are exposed in a command line interface:

Command	Description
./GraphSTEP read <output directory>	Transforms the graph back to a STEP file
./GraphSTEP create <file path>	Creates a given STEP file into a graph
./GraphSTEP delete	Deletes all data of a graph
./GraphSTEP filter	Filters branches belonging to specific nodes
./GraphSTEP restoreFilter	Loads the filtered data, stored in the macro database, back to the productgraph
./GraphSTEP filter-brep <part name>	Filters the boundary representation of a part
./GraphSTEP restore-brep <part name>	Loads the filtered boundary representation to the product graph and links it to the desired part
./GraphSTEP add-part <file path> <part name> <assembly name>	Adds a new part and links it to the assembly
./GraphSTEP duplicate-part <part name> <assembly name>	Duplicates a given part
./GraphSTEP move-part <part name> <x pos> <y pos> <z pos>	Moves a part to a desired position
./GraphSTEP version-control-test <data directory>	Demonstrates a version control pipeline

Library

You can bind the GraphSTEPLib in your own project. Use cli.cpp and CMakeLists.txt as an example.

Node.js Interface

Import the GraphSTEP addon:

var addon = require("bindings")("graphstepAddon");

• Make sure the addon can be found by your script. Adjust your path if this is not the case.
• Examples for the usage of the addon are contained in the examples directory.

☎ Contact

You are welcome to submit issues, send pull requests, or share some ideas with us. If you have any other questions, please contact 📧: Adrian Pustelnik.

✍ Citation

If you find GraphSTEP useful to your research, please cite our work:

@article{Moenck.2024,
  author = {Moenck, Keno and Pustelnik, Adrian and Koch, Julian and Sch{\"u}ppstuhl, Thorsten},
  year = {2023},
  title = {GraphSTEP: concurrent, cloud-based, lifecycle-oriented editing and updating of product data},
  pages = {678--683},
  volume = {120},
  issn = {22128271},
  journal = {Procedia CIRP},
  doi = {10.1016/j.procir.2023.09.058}
}

🙏 Acknowledgement

NIST's SFA and stepcode that helped during the course of this work.