Chris Heit, Application Engineering Specialist
May 18, 2021
Additive manufacturing has been increasing in popularity across the manufacturing industry in recent years. In addition to more traditional 3D printers carrying out these operations, industrial robots are also being employed to carry out additive jobs. While robot additive systems are often much more expensive than their 3D printer counterparts of comparable print volume, there are a few key reasons to choose them to control your extruder:
More Degrees of Freedom
A typical 3D printer contains only 3 degrees of freedom (there are some with more). They move along X, Y, and Z directions. An industrial robot arm comes with up to 6 or 7 axes on the arm, alone. Coupled with optional external axes (either workpiece positioners to move the print bed, or robot positioners to add even more axes of movement to the robot arm, or both), robot additive systems can essentially print in infinite directions.
Collaboration with Other Robots and Applications
Dual extrusion printers are common, but they are often limited in functionality and how they can collaborate. Using robots opens the door to incredible possibilities for collaboration with other non-additive applications. A simple tool change can let a single robot printing cell not only deposit additive material but then also perform a material removal or finishing operation on the deposited material. The robot switches the print head for a spindle, and both processes can be performed within the same robot cell. This saves space within the manufacturing environment, as well as time and human intervention to move the part between different stations. Multiple robots can also be programmed to collaborate and work on the same piece at the same time, further improving the time savings.
There are other advantages to going with a robot additive system, with more degrees of freedom being the greatest. These advantages that are gained by using a robot additive system do not come free, with regards to the expense and complexity of the operation. Programming an industrial robot is much more complex than programming a 3D printer that the two experiences do not even compare. Of course, this is not to be seen as a roadblock to using these systems, only an obstacle that needs to be overcome. In fact, it has been overcome.
OLRP is often leveraged for programming robotic additive operations. The simple reason for this is that it alleviates a lot of the complexity of programming these operations. More specifically:
OLRP makes it easier to program the additional axes of a robotic system
A typical slicer software, which takes in a CAD model and outputs a series of points that a printer will need in order to print the given model, will only produce coordinates of points for a typical 3D printer to follow. Usually, the output file will be a GCODE file. OLRP software packages, like OCTOPUZ, can import these GCODE files into virtual robot cells, convert the simple coordinates into robot code, and program any additional external axes that may be needed. The simple coordinates output by the slicer software assumes only one printing direction: from the bottom of a printing bed, upwards. If you intend on printing in other directions (very likely, if you are using a robotic additive system), OCTOPUZ can easily re-orient your print paths and program all the axes of the robot cell to accommodate these new printing directions. Without and OLRP software, this would be extremely difficult.
OLRP makes it easier to solve robot errors
As mentioned previously, the additional axes in a robot cell bring a lot more potential for errors, such as joint limits and singularities. Resolving these errors on a teach pendant is difficult at the best of times, and for an additive path of hundreds of thousands (or more) points is unrealistic. OLRP software packages let you easily screen for and fix these errors before the program reaches your teach pendant. OCTOPUZ, for example, searches for these kinds of errors in a robot program and automatically fixes them for the user.
There is simply no comparing the experience of programming a robotic additive operation on a teach pendant versus in an OLRP software like OCTOPUZ. The OLRP software will always be faster, easier, and more efficient. 3D printing and additive manufacturing with industrial robots has seen significant growth in the last few years. With the issues of complexity being resolved by OLRP, it is a safe bet that this growth will continue and even accelerate, given its enormous potential to improve many manufacturing processes.