Introduction to Industrial Robotic Automation for Architectural Manufacturing

General Introduction to AutomationInstructor Brian Ringley

What is an “Industrial Robot”

An industrial robot, commonly referred to as an industrial robotic arm, can be identified by the following common characteristics:

• Automatically controlled

• Reprogrammable

• Multipurpose manipulator

• Programmable in three or more axes

Automatically Controlled

Industrial robots are automated, meaning that they operate by themselves with little or no direct human control. This is achieved through a robotic controller, a computing device that calculates robotic movement by reading code and sending motion instructions to the motors of the robot.

Note: Each axis of motion is controlled by one motor. For example, a six axis robot has six motors, one at each articulated joint.

The IRC5, ABB’s fifth generation robot controller. The IRC5 unit is modular and can control up to 36 synchronized axes.

Wait, Did You Say 36 Axes?

“Kara” video game concept trailer from Heavy Rain

Seriously, 36 Axes?

A behind the scenes look at how robotics are utilized at the Tesla Motors factory by WIRED Magazine.

Some robotic operations pictured are synchronously controlled, while others operate independently but are times to work together. This timing is set up and monitored via a PLC or “Programmable Logic Controller.” A PLC engineer often has a background in electrical and/or mechanical engineering.

Can you tell which is which?

Okay, Now You’re Just Showing Off

Demonstration of ABB IRC5 controller “Multi-Move” technology with Fanta

Reprogrammable

Industrial robot controllers encode motion information to the joint motors by reading machine code.

Note: Industrial robot programming code is different than the common G code used in CNC programming, and is typically proprietary. For example, we use the ABB RAPID language with ABB controllers.

Text-Based Programming (RAPID)

RAPID code can be edited in most text editors and mark-ups can be imported into apps like Notepad++. However, it is easiest to program within the RobotStudio environment.

The RAPID editor is similar to the RhinoScript editor, with conveniences like instant semantics checks, argument pick lists, and syntax coloring.

Graphical Programming (RobotStudio)

Screen shot from RobotStudio. It would be very tedious to use text-based programming for an entire robot program so, just as we do with CNC programming, we use a graphical editor that allows us to manipulate and simulate a CAD model.

The difference here is that we can synchronize the code very quickly without the need to specify a post-processor, as we are using ABB programming software for ABB robot controllers.

Parametric Programming (HAL)

HAL is an example of an industrial robotic programming plugin for Grasshopper which allows users to simulate their robots and generate RAPID code in near real time. The advantage is that the code output is directly tied to a parametric model, allowing the user to bypass tedious importing and re-importing of CAD geometry into RobotStudio.

Image from hal.thibaultschwartz.com

Multipurpose ManipulatorIndustrial robots are different from task-specific fabrication equipment such as 3D printers, laser cutters, and CNC mills in that they are intentionally unspecific and, as a result, can be used for an almost endless range of applications. The arm is fitted with what are called “end effectors” or “end-of-arm tooling” which are specific to whichever application the robot is intended to perform. Common industrial robot applications include (but are certainly not limited to):

• Welding

• Laser Cutting

• Painting

• Palletizing

• Machine Tending

Robotic Welding

Robotic arms can weld along curves using MIG or TIG welding end effectors, or they can weld at points using spot welding end effectors. Spot welding end effectors can be open/closed and on/off, whereas MIG/TIG welders are only on/off.

Note: Unlike CNC end mills, these tools can’t be directly touched off, but rather have an offset distance from the target not unlike a laser cutting head’s focal length. ABB robotic arm with spot

welding end effector

Robotic Laser Cutting

Laser tubes, where wattage generates the laser beam, and the ensuing optics assembly have to be in a straight line for a robotic arm, versus configured with mirror turns as in a typical laser cutter.

Robotic Painting (ASM)

Robotic painting arms use ASM, or Automated Spray Method, to rapidly and evenly coat cars and airplane components with paint. These robots are covered in draped cloth which allows the robot its full range of motion while protecting the arm from paint.

Robotic Palletizing

Robotic palletizing is used to quickly and accurately stack objects onto pallets. These robots are known for long reach, high payload, and fast speed and typically require only three axes.

Robotic Grippers

The end effectors used for palletizing and stacking operations are fairly wide ranging, and include servo grippers, pneumatic grippers, vacuum holders, and more.

Robotic Machine Tending

Robots can be integrated into assembly line or other manufacturing processes. For example, a robotic arm may be used to retrieve finished parts from a CNC machining center and reload the machine with fresh stock.

Programmable in 3 or More Axes

An industrial robotic arm requires 3 axes (or “degrees of freedom”) because 2 axes are required to reach any point in a plane and the third is required to reach any point in space. Think of the 3 axes as yaw, pitch, and roll rather than X, Y, and Z as in a CNC mill.

Typical 6 Axis ArmA typical 6 axis arm (as well as our own IRB 140 arm) have 6 axes that work in tandem (interpolate and configure) to reach targets. Ranges of motion for the axes are:

• Axis 1 (base twisting) 360d

• Axis 2 (base bowing) 200d

• Axis 3 (forearm flapping) 280d

• Axis 4 (forearm twisting) 400d*

• Axis 5 (wrist flapping) 240d

• Axis 6 (wrist twisting) 800d*

*unlimited but set to default value

Robot Reach

Reach is more of an art than a science and is based on joint interpolation as well as joint configuration (deciding between multiple possible joint positions to reach a target). The image to the left is a typical reach diagram for the ABB IRB 140. The 810mm front reach is almost 32in.

Reach is also dependent on how the robot is mounted.

Robot Mounting

Robots can be bolted to steel tables or other rigid bases but are often wall or ceiling-mounted to enhance reach relative to the intended robotic application.

If the object the robot is mounted to can also be moved via the robotic controller, such as gantry or rail-mounting, this is considered an additional axis or additional axes depending on the configuration.

External Axes

As mentioned, axes in a robotic system can be limited to a single robotic arm, can be a summation of multiple robotic arms synchronized through a single robotic controller, and can also include external axes (also synchronized through the same controller). Typical external axis configurations include:

• Gantry

• Rails

• External Workpiece Positioners

• Robotic Arm as End Effector for Other Robotic Arm

Robot on Gantry

Example of robotic machine tending with ABB 5 axis robot on linear gantry

Robot on Rails (or “Tracks”)

Tracks are useful for allowing robots to work on larger workpieces than fit into the robot’s initial reach, for longer range machine tending, and for the ability to perform different research or different tasks at various locations.

External Workpiece Positioners

Coordinated motion between two IRB 1600ID arc welding robotic arms and an IRBP R (rotary) type positioner.

Robot as End Effector of Another Robot

Robots can actually be mounted to other robots to increase reach and articulation at the workpiece. This is a Fronius welding effector on an IRB 140 (6 axis) which is in turn mounted to an IRB 660 (3 axis). A chassis (not pictured) is being welded on an R type positioner (1 axis). This 10 axis welding system is the IRB 800.

Robots in Architecture

Robots are increasingly becoming a focus of architectural research and architectural production. Certain fabrication labs (Stuttgart ICD, ETH Zurich, Carnegie Mellon, Michigan, Sci-Arc Robot House, and UCLA) have emerged as premier facilities for architectural robotic arm research and pedagogy.

The Association for Robots in Architecture has emerged to help create a community around these efforts, and hosts a conference on the subject once every two years titled “Rob|Arch.”

Robotic Masonry Stacking

“Pike Loop” was a project by architects and ETH Zurich researchers Gramazio & Kohler which transported a robot to a location within a trailer where it proceeded to stack a 72’ long brick structure.

Robotic Masonry Stacking

Autonomous stacking has not been limited to robotic arms - the same researchers Gramazio & Kohler are now looking into the autonomous construction of masonry walls by drone assembly. This project is titled “Flight Assembled Architecture.”

Wait… Drones Can Do That?

Also at ETH Zurich (a pretty cool place, right?) researchers are exploiting the ability to program drones to learn their positions and to maintain balance with and against physics-based interactions. As opposed to axes drone motion is controlled through its rotors.

Okay Drones Are Awesome

Oh my gosh this video is sweet.

Note: Notice the mention of roll, pitch, and yaw as we discussed with robotic arm motion.

The Future of Drones

Imagine a world where we interact with these devices in our daily life.

How will this affect manufacturing? How will this affect architecture and urban space? How will this affect our social behavior?