Workshop: Robotic Fabrication with COMPAS FAB

Princeton University

28-30 June + 2 July 2021

Overview

• Intro
• Kinematics
• Path planning
• Scene and end effectors
• Pick and Place
• Assemblies
• Robot control

👉 Slides

Examples

Introduction

• Primitives

  • Primitives
  • Operations
  • Constructors
  • Equivalences to built-ins
  • Transforms

• Shapes

  • Shapes
  • Shapes in Rhino

• Mesh datastructure

  • Mesh in Rhino
  • Mesh in Blender
  • Mesh in GHPython
  • Mesh from scratch
  • Mesh stand-alone viewer
  • Queries: vertex degree
  • Queries: vertices on boundary
  • Queries: face neighbors
  • Queries: vertex neighbors
  • Queries: edge strip
  • Queries: edge loop
  • Vertex normals in Rhino
  • Flip cycles
  • Artists in Rhino
  • Boolean operations with CGAL
  • Boolean operations in Rhino

• Network datastructure

  • Network from scratch
  • Network in Rhino
  • Network attributes
  • Network stand-alone viewer
  • Queries: node neighbors
  • Queries: shortest path
  • Interactive network
  • Serialization
  • Serialization in Rhino
  • Serialization of complex types
  • Network Koch snowflake

• Remote Procedure calls

  • Basic remote procedure call

Robotic fundamentals

• Frame

  • Construct a frame
  • Point in frame
  • Frame in frame
  • Box from world to local
  • Box from world to local in Rhino

• Transformation

  • Examples
  • Inverse transformation
  • Pre-multiplication
  • Pre vs post multiplication
  • Matrix decomposition
  • Transform point and vector
  • Transform multiple
  • Change of basis
  • Transform between frames
  • Box from world to local in Rhino

• Rotation

  • Construct a rotation
  • Robot TCP orientations
  • Euler angles
  • Axis angle
  • Quaternions

Kinematics and Models

• Robot Model

  • Visualize URDF in Rhino
  • Visualize URDF with meshes in Rhino
  • Load from local files in Rhino
  • Load from Github package
  • Load from Github package in Rhino
  • Load and manipulate in Grasshopper
  • Load from ROS
  • Define programmatically
  • Build your own model

• Configuration

  • Joint types
  • Construction and merge

• Kinematics

  • Forward Kinematics
  • Forward Kinematics in Rhino
  • Inverse Kinematics
  • Inverse Kinematics in Rhino
  • Inverse Kinematics in Grasshopper

ROS and MoveIt

• ROS Basics

  • Verify connection
  • Interconnected nodes: Listener
  • Interconnected nodes: Talker in Grasshopper
  • Interconnected nodes: Talker

• ROS & MoveIt planning with UR5

  • Load robot
  • Load robot in Rhino
  • Forward Kinematics
  • Inverse Kinematics
  • Cartesian motion planning
  • Cartesian motion planning + graphs
  • Free space motion planning
  • Free space motion planning + graphs
  • Constraints

• Planning scene and end-effectors in MoveIt

  • Load scene in Grasshopper
  • Add objects to the scene
  • Append nested objects to the scene
  • Remove objects from the scene
  • Attach tool
  • Detach tool
  • Cartesian motion planning with tool

Assemblies

• Pick and Place

  • Simple Pick and Place in Grasshopper

• Graphs and Orders

  • Linear order
  • Color-mixing lattice
  • Color-mixing lattice in Rhino
  • Partial order
  • Network concepts
  • Using NetworkX

• Assembly models

  • Basic model of a network-based assembly class
  • Network-based assembly planner

• Sequence assignments

  • Default sequence
  • Linear sorted sequence

• Scripted Assembly Planning

  • Plan pick trajectory
  • Plan all brick placements
  • Clear planning scene
  • Clear all trajectories

• Assembly visualization

  • Grasshopper viewer

• Assembly Design for tomorrow!

  • Assembly designs

Robot Control with COMPAS RRC

• Communication

  • Hello World
  • Send instruction
  • Send instruction with feedback (blocking)
  • Send instruction with deferred feedback (non-blocking)

• Basic setup

  • Set tool
  • Set work object
  • Set acceleration
  • Set max speed

• Motion instructions

  • Get/Move to frame
  • Get/Move to joints (Configuration)
  • Get/Move to Robtarget
  • Move to home configuration

• Utilities

  • No-op/ping
  • Print Text on flex pendant
  • Wait time
  • Stop/Pause program
  • Stopwatch on the robot
  • Custom instruction

• Input/Output signals

  • Read analog input
  • Read digital input
  • Read group input
  • Set analog output
  • Set digital output
  • Set group output

• Brick assembly

  • Work objects
  • Pick and Place bricks

Requirements

• Minimum OS: Windows 10 Pro or Mac OS Sierra 10.12
• Anaconda 3
• Docker Desktop Docker Toolbox would also work but it's a bit more annoying. After installation on Windows, it is required to enable "Virtualization" on the BIOS of the computer.
• Rhino 6/7 & Grasshopper
• Visual Studio Code: Any python editor works, but we recommend VS Code + extensions as mentioned in our docs

Installation

We use conda to make sure we have clean, isolated environment for dependencies.

First time using conda? Make sure you run this at least once:

(base) conda config --add channels conda-forge

Clone this repository and create a new conda environment:

(base) cd path/to/workshop_princeton_2021
(base) conda env create -f environment.yml
(base) conda activate fab21

Alternatively, create environment manually

The conda environment can also be manually created:

(base) conda create -n fab21 python=3.8 compas_fab>=0.19.1 --yes
(base) conda activate fab21

Mac

Also install python.app after activating the environment:

(fab21) conda install python.app

Verify installation

(fab21) python -m compas

Yay! COMPAS is installed correctly!

COMPAS: 1.7.1
Python: 3.8.10 | packaged by conda-forge | (default, May 11 2021, 06:25:23) [MSC v.1916 64 bit (AMD64)]
Extensions: ['compas-fab', 'compas-slicer', 'compas-cgal', 'compas-rrc']

Install on Rhino

(fab21) python -m compas_rhino.install
(fab21) python -m compas_rhino.install -v 7.0

Update installation

To update your environment:

(fab21) conda env update -f environment.yml