Armed with a vast array of computer aided design (CAD) software along with 3D printers that can create specialized parts and equipment, NTT IndyCar Series team Andretti Autosport is taking that expertise to the medical field.
Team owner Michael Andretti’s team is building a key part for medical face shields. These shields protect first responders, nurses and doctors from moisture droplets. The droplets can spread the COVID-19 virus from one human to another.
Simply put, the design process goes from Andretti Autosport’s CAD system to an intermediate piece of software and then the printer makes the part.
Andretti Autosport senior development engineer Aaron Marney is in charge of this project along with team technical director Eric Bretzman and Marissa Andretti.
“We went into our shutdown and have a few resources sitting there,” Marney explained to NBCSports.com. “We have been reading some stories about people wanting to help out the medical community. I reached out to our technical director, Eric Bretzman, if he would be open to doing something like this. That started the conversation.
“At the same time, Marissa Andretti on her own had reached out to Eric to ask if we could do something in this area. Me and Marissa connected. We wanted to do something and see what the shape looked like on it and what we could do, what the resources and how big of an impact we could make.
“We reached out Stratasys, the company that manufacturers the 3D printer. They are a technical partner of ours’. They were in the infancy of a program where they were printing PPE (personal protective equipment) for hospitals that had approached them. Once we talked about it internally, and what we could put into it, we jumped on board and have been helping them the last 3-4 weeks now.”
Andretti Autosport is making the frame that goes around the crown of the head and hold the clear face shield. Stratasys has a relationship with Medtronic, the company that makes the actual shield.
The simple design is a one-piece part that has a mounting for the actual shield. An elastic band can be attached to the frame to keep the face shield on a person’s head.
Andretti Autosport ships batches of 100 to Stratasys in Eden Prairie, Minnesota. After that, they are shipped to Medtronic for final assembly, including the clear lens.
“The crew is me and another person,” Marney said. “We are the point people on 3-D printing for our company. I go in and service the printer. When we have both machines going, we can print about 35 a day. Each machine takes about 20 hours to produce a batch of parts. We go in, pull the parts off, clean them and when we get 100 of them, we box them up and ship them off.”
The frame is made with “ASA” plastic, similar to “ABS” plastic. Don’t look up those acronyms, though, because the answer will never be revealed.
“It doesn’t stand for anything,” Marney explained. “It’s a name they came up for it. It’s a plastic polymer that has a little more bendability than ABS plastic. It is a little bit is something we use for a lot of prototypes and finished pieces like templates and fixturing. It is also pretty good for this application as well.”
The 3D printer is an extremely useful tool for any IndyCar Series team because it can create a wide range of parts.
“It has a pretty decent array of materials it can use,” Marney continued. “We do lots of pit equipment. Fans and blowers that keep the car and driver cool. We make bolts for composite pieces along with holders and brackets. The more we work with it, the more in-use parts we can make. We also use it for a lot of templates and for prototypes as well. There are a lot of in-use parts and prototypes to see how things fit together and templates to drill holes.”
So, in detail, how does the 3D printing process really work?
To give that question the explanation it deserves, let’s have Marney explain it.
“There is a small group of us that would take an idea, such as the driver cooling for the aeroscreen,” Marney said. “There is a little duct that pipes air to the helmet. If we take a fan or a tube or a fitting, we will design that in our CAD system to make a 3D model of it. We would then evaluate it. The good thing about 3D printing is you can come up with some organic looking shapes and tailor it for what you need. You are not limited by standard manufacturing methods like mills or lathes or regular sheet metal. You can make the part look like anything you want it to, exactly tailored to what you need.
“We would evaluate the abuse and temperature and select the material based on that. Then, we introduce that into the software that Stratasys has that queues up all the tool paths and programming for the printer. We put the geometry in that to figure out the orientation we want to put it in. It has different strengths because it is building it one-ten-thousandths of an inch at a time. That can vary on what you are doing. It is building up these layers of plastic and melting them together. We have to figure out the compromise on how to build it, how heavy does it need to be, how solid does it need to be or how light it needs to be. We can make adjustments to the tool path, queue the job up and it takes care of the rest.
“Depending on the material, we have to go to a wash process. As it goes through and builds these layers, there is a little bit of a cleanup, but it is fairly minimal.
“We would take it, catalog it and then start implementing it.”
Once the NTT IndyCar Series returns to action, Marney will continue his role as senior development engineer. He helps with the team’s wind tunnel testing program. He is also involved in design work for electrical systems and other mechanical systems on the car.
As a project manager, he doesn’t have to travel to any race anymore. He was a road warrior until 2018. But if needed, his bags are packed to hit the road.
“If I need to fill in for somebody, I occasionally go to the track, but not on a regular basis,” he said.
Stacks of Visor Frames