Author Mary Roach Talks Body Science, Space Toilets, and Cars
About this episode
Mary Roach brings body-science curiosity to the DRIVE conversation, from a signed “emesis basin” she keeps in her glove box to how astronauts handled waste in microgravity. The talk then pivots to race and crash logistics: hydration during long yellow flags, endurance driver rotations, and how seatbelts/airbags are validated with crash sleds and even cadaver-calibrated instrumentation. The episode closes with how automated cars and even horns become software-controlled, culturally shaped signals.
glove box
"We started with a story about an item that she always keeps in her glove box of her car. [39.4s] You know what I have in my glove box, and I guarantee you no one else has this."
A glove box is the little storage compartment in the front of the car, usually on the passenger side. It’s where you can keep things you want to have handy.
A glove box is the lockable storage compartment inside a car, typically on the passenger side of the dashboard. People use it for small items like manuals, registration, and—here—an emesis basin.
emesis basin
"It's, and I'm going to have to explain it, it's an emesis basin. [52.4s] You might know because you've spent time in hospitals, but it's that little plastic thing [57.4s] that if somebody's going to throw up, you put it right under."
An emesis basin is a special bowl/container meant for throwing up. It’s the kind of thing you’d see in a hospital, and it’s shaped to catch vomit safely.
An emesis basin is a container designed specifically for vomiting, often used in hospitals. The host describes it as a curved plastic receptacle that you place under someone who’s about to throw up—then ties it to the astronaut-signed story.
urine containment device (space/medical context)
"See what they had on the Apollo missions, they had, it was a urine containment device, so it's basically, it's a bag... and a sort of like a condom-ended thing that you would pee in."
This is a device that collects urine so it doesn’t spill when someone can’t get up. In the description, it’s basically a bag with an attachment that directs where the urine goes.
A urine containment device is a system designed to collect and contain urine when a person can’t easily leave their seat or position. The transcript describes it as a bag plus a condom-ended attachment, emphasizing how it prevents spills during long periods of confinement.
liftoff (spaceflight context)
"So you're waiting, again, like what you're describing, for liftoff, you're in there for hours and hours, and you can't leave to go to the bathroom."
“Liftoff” means the rocket starts flying. The point is that astronauts can’t just get out for a bathroom break right away.
“Liftoff” is the moment a rocket begins its ascent from the launch pad. In the Apollo-mission context here, it sets the timing constraint for how long astronauts must remain inside the spacecraft before they can use a restroom solution.
endurance race driver changes
"And it's one of my first questions I have for our pro drivers, and you've got two groups of people... and then there's a third category... because in an endurance race, they're multiple drivers. In a 24-hour race at Le Mans, you'll have four drivers."
In long races, the same car is driven by several people. When one driver hands off to the next, whatever happened before (including bathroom gear) can affect the next driver.
In endurance racing, multiple drivers share the same car over a long event, so the car’s interior and equipment get used by different people back-to-back. That makes “bathroom tactics” a practical strategy issue, not just a personal comfort thing.
Le Mans 24-hour race
"because in an endurance race, they're multiple drivers. In a 24-hour race at Le Mans, you'll have four drivers."
Le Mans is a famous long-distance race that lasts 24 hours. Because drivers rotate, anything like bathroom gear can matter for the next person getting in.
Le Mans is famous for its 24-hour endurance format, where teams rotate drivers and keep the same car running for an entire day. The race’s long duration is why driver “tactics” like bathroom solutions become a real part of the experience.
Ford
"Because that's not required by law. He said, because my daughter died in a car accident. [1046.3s] And I was a doctor at the Philadelphia Children's Hospital. And I realized I could save more lives working at Ford than there. So I've been a safety engineer at Ford."
Ford is a car company. Here, the guest is talking about how Ford engineers test and design safety gear like seat belts and airbags.
Ford is a major automaker that employs safety engineers and designs crash-safety systems like airbags and seat belts. In this segment, the speaker frames Ford as the place where safety testing requirements and engineering decisions get made.
airbags
"So I'm trying to learn about our safety systems, our airbags, our seat belts, where they're placed on the body for a different kind of instrument."
Airbags are the cushions that pop out in a crash. They help protect your head and chest by slowing you down more safely.
Airbags are inflatable safety cushions that deploy during a crash to reduce the force of impact on occupants. Their placement and timing are engineered to work with how the body moves in a collision.
seat belts
"So I'm trying to learn about our safety systems, our airbags, our seat belts, where they're placed on the body for a different kind of instrument."
Seat belts keep you from hitting the steering wheel, dashboard, or windshield. In crashes, they help hold you in place so you don’t move as violently.
Seat belts restrain occupants during a crash, controlling how quickly and how far the body moves. Modern belt systems are designed to work alongside airbags so the occupant’s motion is managed in a predictable way.
crash test dummies
"Initially, and there weren't even seatbelts, little lone airbags, and crash test dummies. In order to calibrate them, they had to do all this work with cadavers."
Crash test dummies are special mannequins with sensors. They help engineers measure what happens to a person’s body in a crash so cars can be made safer.
Crash test dummies are instrumented mannequins used to measure forces and injury risk during vehicle impact testing. They’re calibrated so their sensors can translate crash conditions—like deceleration and impact forces—into data that engineers use to improve safety designs.
cadavers
"In order to calibrate them, they had to do all this work with cadavers. You needed to know, okay, this dummy, this instrument can tell you what's the force, what kind of deceleration is happening."
Cadavers are human bodies used for research. The segment explains that early safety testing needed real injury data to understand what the crash measurements meant for the body.
Cadavers were used historically to understand how crash forces translate into real human injuries and to calibrate early test instruments. The point in the segment is that engineers had to connect sensor readings to actual injury outcomes.
deceleration
"You needed to know, okay, this dummy, this instrument can tell you what's the force, what kind of deceleration is happening."
Deceleration is how quickly the car slows down. In a crash, that slowdown rate affects how hard the body gets hit and how much it gets stressed.
Deceleration is the rate at which a vehicle slows down during a crash. Crash testing uses deceleration data because it strongly influences how the body loads up—how hard and how quickly the occupant is forced to stop.
crash sled
"Usually in the beginning, sometimes the engineers themselves up through about 20 miles an hour, they'd get on the crash sled, the deceleration sled."
A crash sled is a rig that simulates a crash by quickly slowing down, like a controlled “impact test.” It lets engineers test safety systems repeatedly without destroying a whole car every time.
A crash sled is a test platform that accelerates and then rapidly decelerates to simulate a vehicle crash in a controlled way. Instead of crashing a full car on a track, engineers can repeat the same impact conditions to evaluate restraints like seatbelts and airbags.
head-on crash dummy
"And I think people, you know, might not be aware of it... first there was the head-on crash dummy, and then the t-bone crash dummy,"
A head-on crash dummy is a “test person” used to simulate what happens in a front-end crash. Engineers use different dummy setups depending on the type of crash they’re studying.
A head-on crash dummy is a specialized crash test mannequin configured to represent how a human body responds to a frontal impact. Different dummy types are used for different crash geometries so engineers can evaluate safety systems under the right loading conditions.
t-bone crash dummy
"first there was the head-on crash dummy, and then the t-bone crash dummy,"
A t-bone crash dummy is used to test side-impact crashes, like when one car hits the side of another. It helps engineers check whether safety systems protect people in that specific kind of collision.
A t-bone crash dummy is a crash test mannequin intended for side-impact (intersection-style) collisions. Because the forces and body motion differ from a frontal crash, engineers use a dedicated dummy type to validate restraint performance for that scenario.
underbody blast
"the military came up with a crash test dummy for underbody blast, because that's completely different kind of forces coming up from below if you drive over an IED."
Underbody blast means an explosion happens under the car. That kind of force is different from a normal crash, so engineers use special tests to understand how people would be affected.
Underbody blast refers to explosive forces that originate beneath a vehicle, such as from an IED. It produces a different force pattern on occupants than typical road crashes, so specialized testing and dummies are used to study those effects.
IED
"because that's completely different kind of forces coming up from below if you drive over an IED."
IED means an improvised explosive device. It’s a kind of bomb that can detonate under a vehicle, which is why safety testing has to account for that special kind of danger.
IED stands for improvised explosive device. In the context of vehicle safety testing, it’s used to describe threats that can detonate under a vehicle, creating blast forces that require different safety engineering than standard crash impacts.
rear wheel drive
"He drove a rear wheel drive Mustang in Dartmouth. It was mid 60s vintage burgundy Mustang."
Rear-wheel drive means the back wheels get the power. It can make the car feel different when you speed up or turn compared with cars that drive the front wheels.
Rear-wheel drive (RWD) means the engine sends power to the rear wheels. That layout often gives a different balance and feel than front-wheel drive, especially when accelerating or cornering.
Ford Mustang
"He drove a rear wheel drive Mustang in Dartmouth. It was mid 60s vintage burgundy Mustang."
The Ford Mustang is a famous American sports car. Here they’re talking about an older, mid-1960s one that drives the rear wheels, which changes how it behaves on the road.
The Ford Mustang is a classic American pony car known for its sporty styling and strong enthusiast following. In this segment, the host specifically mentions a rear-wheel-drive Mustang from the mid-1960s, which matters because drivetrain layout affects how the car feels and handles.
minimum speed limits
"Back then, they were not just maximum speed limits. They were minimum like you couldn't go slower on the freeway."
A minimum speed limit is the slowest speed you’re allowed to drive on some roads. Going slower than that can cause problems for other traffic.
Minimum speed limits are rules that set the slowest legal speed on certain roads, often to keep traffic flowing and reduce hazards from unusually slow vehicles. The host uses this to explain why driving “below” the minimum can be risky or annoying to other drivers.
spark plugs
"The thing with that Vespa is that it would foul the spark plugs. So, I'd have to stop and I'd get out... clean off the electrodes in the contacts."
Spark plugs are what create the spark that starts combustion in an engine. If they get dirty, the engine can run poorly, so cleaning them can help.
Spark plugs ignite the air-fuel mixture in an engine’s cylinders. If they get fouled (covered with deposits), they can misfire, which is why the host says they had to clean the electrodes/contacts.
Mini Cooper
"I have a 1960 Mini Cooper, which I absolutely, one of my favorite cars... it was actually transverse. So, the engine is mounted not kind of north-south, east and west."
The Mini Cooper is a famous small British car. The key idea here is that the engine is mounted sideways, which helps the car fit more usable space inside.
The Mini Cooper is a small British car famous for its compact packaging and front-wheel-drive layout. This segment highlights the 1960 Mini Cooper’s transverse engine design (engine mounted sideways), which frees up more interior space in a tiny footprint.
transverse
"It was not only a four cylinder front wheel drive, but it was actually transverse. So, the engine is mounted not kind of north-south, east and west."
A transverse engine is mounted sideways in the engine bay. In a small car like the Mini, that layout helps make more room inside.
A transverse engine is mounted sideways (left-right) across the car, rather than front-to-back. The Mini’s transverse layout helps maximize interior space by shortening the engine bay and improving packaging for a small car.
four cylinder front wheel drive
"It was not only a four cylinder front wheel drive, but it was actually transverse."
“Four cylinder” means the engine has four working cylinders. “Front wheel drive” means the front wheels do the driving, which affects how the car feels and fits.
“Four cylinder” describes an engine with four combustion cylinders. “Front wheel drive” means the engine’s power goes to the front wheels, which strongly influences packaging and how the car drives compared with rear-wheel drive layouts.
automated car
"“...more importantly, an automated car? Should you have a driving disposition in an automated car? Like, I want to get to the airport really quick...”"
An automated car can do parts of driving on its own. Instead of you deciding how aggressive or careful it feels, the car’s software decides.
An automated car is a vehicle that can perform driving tasks without a human actively controlling every action. In these systems, the “driving disposition” (how it behaves—quick, cautious, assertive) becomes a design choice, not just a driver habit.
Waymo
"“...If you get into Waymo today and you got into Waymo two years ago, they drive completely different. The Waymo drives very human like now...”"
Waymo is a company that builds self-driving cars. The point here is that their cars’ behavior has changed over time.
Waymo is a self-driving technology company known for evolving its autonomous driving behavior over time. The host contrasts “two years ago” vs “today,” highlighting how Waymo’s driving style can change (e.g., whether it will go through a yellow light).
digital safety devices
"“...in the world of automation and cars and also digital safety devices, like a horn now is a digital thing. It's no longer analog...”"
This means safety features that are controlled by the car’s computer. Instead of being fixed, they can be designed and adjusted in software.
“Digital safety devices” refers to safety-related vehicle functions that are controlled by software and electronics rather than purely mechanical or analog behavior. The segment uses the horn as an example of an output that can be treated as a configurable digital feature.
output sensors
"“...all of these output sensors, they all have the option of being customized. And we have to decide on those.”"
The car has electronic signals it sends out to the world. The episode is saying those signals can be customized, so the car has to “choose” what it tells other people.
“Output sensors” is used here to describe vehicle signals/outputs that interact with the outside world (like sound or alerts) and are controlled electronically. The key idea is that these outputs can be customized, so designers must choose what the car “communicates” to people around it.
horn
"“...like a horn now is a digital thing. It's no longer analog... The most challenging horn design?... India. Oh, India...”"
A horn is the car’s warning sound. The episode is talking about how the horn’s design and behavior can be engineered to be loud, reliable, and long-lasting.
In modern vehicles, a horn can be implemented as an electronically controlled output, meaning its behavior can be shaped by software and vehicle systems. The discussion focuses on “horn design” requirements like robustness, longevity, and audibility—especially in different regulatory and real-world driving contexts.
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