Our Stratasys Fortus 400 has been busy during the past few months. I mean really busy. During the month of March we approached full utilization of the machine, and we don’t see that slowing down any time soon.
One of our most interesting projects was to print fixture components for a local aerospace company. That company explained their project and their dire need for parts on a very aggressive deadline. Luckily we had capacity, and we were able to deliver the parts on time. What made this project really gratifying was that we were allowed to learn all about what the parts were being used for.
NASA Docking System
The aerospace company is working on a project for NASA supporting our country’s national space program. NASA has developed a plan to create and implement a new docking system for the International Space Station (ISS). The company that we are working with has been tasked with engineering and building a key component of the NASA’s next generation Docking System.
The current docking system has been in use for decades. In this Russian design, the driver of a spacecraft lines up his vehicle with the ISS, takes aim, and basically drives into the mating docking ring. This brute force system is effective, but it has become obvious that there needs to be a better solution. Since this collision is happening in space, all of the energy is being transferred to the ISS, and the spacecraft and the station can only take so much abuse. Fatigue and degradation of the structure are the primary concerns.
NASA has given specs for commercial crew space vehicles to be equipped with components that are compatible with the NASA Docking System, or NDS. The NDS will allow for a soft capture of spacecraft to reduce the stresses that are imparted during dockings. These commercial crew vehicles will be heading to the International Space Station in late 2017, and maybe sooner if relations with Russia continue to sour. That means that this project was turned from “simmer” to “boil” recently, and led our customer to come to us for help.
3D Printing Saves the Day
Part of our customer’s project was to create a cable system that controls a major portion the NDS. This cable runs around the circumference of the component, and has some tolerances and specs that are quite challenging to meet. They designed a fixture for building wiring harnesses around the NDS. When the aerospace company designed the wiring system around the circumference of the unit, they have a .030” true position tolerance for the cable! The fixture that we helped print simulates the form of the system, and allows them build and place the cable to meet their incredibly close tolerances.
Since there was such a time crunch on the project, and because of the reliability and availability of 3D Printers, it was decided that these fixtures would be built with additive manufacturing. We were able to download the files and get printing right away. Our biggest concern was keeping our Fortus stocked with enough material! Fixture components were printing around the clock for nearly 10 days, most of the time while our Additive personnel was working on other tasks or at home.
The fixture was made from ABS-M30 material. Each section nearly filled the build chamber of our Fortus 400, and they were later assembled into a ring with a 4 ½ foot diameter. The parts looked great out of the machine, but they are really impressive when they’re assembled into the full ring. We are incredibly proud to be doing such important work, and it is a real honor knowing that we printed parts that will allow spacecraft docking to enter a new era.