Ask a Roboticist: Meet Diane

Diane Heinle, a mechanical engineer, answers questions about endurance testing for Stretch, how her team simulates years of wear on robot parts over a brief time in the lab, and why there are bird heads on the cable testers. Read the interview below and watch a conversation with Diane about the “Tick-Tock Room.”

What is your role at Boston Dynamics?
I’m a mechanical engineer on the Stretch Interconnects team. We designed the cables and related hardware to route power and data throughout the robot.

What is endurance testing?
Endurance testing is all about maximizing the reliability of the robot. Warehouses can be very active and dynamic environments with a lot of moving pieces, and Stretch needs to work predictably day in and day out.

Endurance testing can look different for each subsystem on the robot. We’ve learned a lot about wear on components, like slip rings or clock springs or dynamic cables. I’ve been the design captain of the dynamic cables that run along the Stretch arm. The cables move every time Stretch moves a box. So throughout the lifetime of the robot, they experience a lot of motion. For the cables we run isolated jigs for each section of the cable to cycle millions of times, and we figure out when exactly even the smallest wear on a cable jacket or the internal copper starts to occur.

Fast-Forwarding Years of Wear

How do you simulate years of warehouse wear and tear in a shorter time in the lab?
In the lab we run our testers much faster and with more aggressive forces than a robot would ever experience to accelerate the testing. With our testing we could find an issue that might occur in the field years down the line, in a matter of weeks.

Is the goal to try to break the robot?
My goal is not so much to break the robot and find ways to break it, but rather to design a robot that works reliably in the realities of a warehouse environment.

How does this testing translate to Stretch robots that are operating out in the world?
We collect data from customer sites to estimate how many cases we expect Stretch to move throughout its lifetime, which gives us a target number of dynamic cycles that the cables should last. So in our testing, we track how many millions of cycles the design can survive, and that translates to how long the design should work in the field.

Finding issues gives us an opportunity to refine the design or update our maintenance schedules, to avoid operational interruptions years down the line for customers.

Why is it called the Tick-Tock Room?
The endurance lab is called the Tick-Tock Room because the cable testers move back and forth continuously, kind of like a metronome. But our testing rigor actually goes much beyond just the Tick-Tock Room. We have different testing sites at Boston Dynamics and customer sites around the world, which helps give us a wider footprint of testing and much more data and statistical confidence to prove that our designs are robust enough for robot operation.

Why are there bird heads on the cable testers?
The bird heads are a classic Boston Dynamics tradition. We’ve had them on there for years. We actually unintentionally have done endurance testing on the heads themselves, because every time the arm moves, the head nods back and forth. Our industrial cables are engineered to survive millions of cycles, but the novelty rubber masks aren’t going to last that long. We’ve actually gone through quite a few birds and dinosaurs over the years.

The Path to Robotics

What first sparked your interest in robotics?
I have been interested in being an engineer probably since middle school. And then in high school I started to get into robotics, and that’s what I pursued in college. I’ve always liked building things and seeing how different components interact and looking at how mechanisms work. I studied mechanical engineering at MIT with a concentration that was called 206, which focused mainly on robotics.

What advice do you have for aspiring roboticists?
Take a look at all the cool engineering things around you. See if you could find something like a toy car or a record player and take it apart. See if you could figure out how each component is manufactured, how everything fits together and works together, and then how the whole thing might be assembled. I feel like there’s a lot of things you could learn just from looking at the world around you.

What was your first impression the first time you saw a Boston Dynamics robot?
I was a bit starstruck the first time I came to Boston Dynamics and saw the robots. I’ve been watching the videos for so long. The coolest part for me was seeing the robots with the covers off and the sheer density of hardware, with everything fitting together in such a tight space to make the robot functional. It was really cool to start to take a look at those pieces and learn what each thing does, and then have the opportunity to improve it and help design future robots.