The Science Behind the Sensation of Speed

Why does driving a go-cart at 40 mph feel way more exciting than driving an SUV at the same speed? Why is it that some slow cars seem to feel faster than they are? In this article, we'll delve into the science behind the sensation of speed and explore how our brains can trick us into feeling like we're moving at a faster pace.

What actually makes a car feel fast?

When we think of speed, we often associate it with acceleration, horsepower, and other technical specs. However, the perception of speed is influenced by a combination of factors beyond just performance data. Our brain plays a significant role in creating the sensation of speed, which can be affected by various physiological and psychological factors.

The Myth of the "Butt-Dyno"

One popular method for estimating speed involves relying on visual cues, such as how fast we move our eyes or feel the motion of the vehicle. This technique is often referred to as the "butt-dyno." However, a recent study investigated the accuracy of this method, and the results were surprising.

The Science Behind Speed Perception

So, what makes a car feel fast? Our brain processes visual information from the environment, including movement and velocity, to create an estimate of speed. This process involves multiple stages, starting with the perception of motion and ending with the cognitive interpretation of that motion.

In this stage, we notice the movement of objects in our field of vision, such as other cars or pedestrians on the road. The brain then uses these visual cues to make an educated guess about the vehicle's speed based on factors like acceleration and deceleration patterns. However, this process is not always accurate, and there are various biases that can influence our perception of speed.

The Role of Expectations

Our expectations and prior experiences also play a significant role in shaping our perception of speed. For example, if we're used to driving at high speeds or have driven similar cars before, we may be more likely to misjudge the speed of another vehicle. Additionally, our brain can create illusions based on our knowledge of physics or mathematical formulas for calculating velocity.

The Importance of Real-World Testing

To investigate the accuracy of these methods, researchers conducted a series of experiments involving real-world testing. The results provided valuable insights into how different factors affect our perception of speed and which methods are more reliable than others.

The Science Beyond Speed Perception

While the sensation of speed is an important aspect of driving, it's not the only factor that influences our experience behind the wheel. Other elements, such as the type of vehicle, road conditions, weather, and even mental states like fatigue or boredom, can significantly impact our perception of speed and overall driving experience.

Conclusion

The science behind the sensation of speed is complex and multifaceted, influenced by various physiological and psychological factors. By understanding how our brains process visual information and perceive motion, we can better appreciate the intricacies involved in this fundamental aspect of human experience.

Now that you've read about the science behind speed perception, get out there and drive! Just remember to stay safe and follow all traffic laws – but don't worry if you feel like your go-cart at 40 mph is faster than an SUV; it's all just part of the thrill of driving.

WEBVTTKind: captionsLanguage: en- Why does driving a go-cart40 mph feel way more excitingthan driving an SUV at the same speed?Why is it that some slow carsfeel faster than they are?Today, we're gonna look at the sciencebehind the sensation of speed.What actually makes a car feel fast?How your brain can trick youand why a slow feeling carmight actually be a good thing.We did the math.We did some real-world testingand now it's time to see how reliablethe old butt-dyno can really be.Let's go.- You ever think, dang, Iwanna do some cool stuffbut I don't have the right hat?Boom, problem solved.Introducing the firstofficial Kentucky Cobra Hat.Perfect for doing anything in.Perfect for doing stuff like this.Perfect for climbing ladders.Perfect for shredding.Perfect for chilling onthe couch with your boo.She's in the bathroom.I've been waiting so longfor these to come out.We've been working on them for a whileand I'm really, really, really stokedon how they turned out.High quality embroidery on the front.That's the new officialKentucky Cobra logo.Donut hit in the back, alsoembroidered, mesh back.I love the fit, it's my new favorite hat.I can't wait to see you guys wearing them.Post pictures onInstagram, tag me in them.I will repost.That's how you're gonnalook when you buy one.- One of the main reasonsthat it's so difficultto tell what speed you're going by feelis that your body can'tactually feel speed.And you might be saying,"Oh, I can feel, I canfeel speed Jere bear."But you're not actually feeling speed.You're feeling acceleration or G-force.Acceleration is the rateat which speed changes.So if you're holding a constant speed,your acceleration is zero.So if you were in a spaceshiphurdling through space,you wouldn't feel a thing theoretically.Now that's all easy to understandbut this is where it getsjust a tiny bit trickier.Now, acceleration is nota scalar measurement.It's a vector, which meansthat to express accelerationyou'd need to have botha number and a direction.Now, if you want to go arounda corner at a constant 40 mph,the rate at which you'rechanging directionaffects the amount ofG-force your body experiencesand that is determined bythe radius of the corner.This is why pilots cantrain in a centrifuge.A centrifuge mimics theforces the pilot would feelby changing direction in atighter circle at a slower speed.So in a car what that meansis any change in direction,however small it is,results in an accelerationand that sensation iswhat your body feels.Now there are there outsideforces and variablesthat make equations a lot more complicatedbut there's also micro accelerationsthat you might not even be aware of.The bumps in the road, for instance,will accelerate the car upwardsand then back down asit passes over the bump.That accounts for theacceleration of the wheeland every car would experiencea pretty similar microacceleration at a given speed.Where cars start to differfrom each other, however,is everything else betweenthe tire and your body.The suspension, the chassis,even the seat that you're sitting incan have an effect on howmuch of that accelerationmakes it to the driver.How much your butt-dyno can feel.To prove this, we're gonna doa little field testing today.We have an accelerometer appthat's gonna measure G-forcesand we have two cars:we have a lowered FRS,which is the epitome ofslow car feeling fastand we have a Scion XB,which isn't necessarilythat much slower or fasterbut this will prove as our baseline car.We're gonna do the same runon the same street with both carsand we're gonna look at thedata and see what it says.And performing all of these testswill be our fieldcorrespondent: Joey Rassool.- You might rememberme from my show Versusand if you do, I am sorry.Here I'm just gonna betesting, not hosting.That's gonna be Jeremiah's job.- Now neither of these carsare pulling huge G's from speedbut at normal road speeds,the softer sprung cargenerates less change and acceleration.- So it's not about which car is faster.We can always tell which car is faster.This is about which car feels fast.And I know that in this car,I have accidentally gotten tolike 80 or 90 on the freewaybecause I didn't even thinkthat I was going that fast.And yes, like there isgonna be a difference.These cars have different zero to sixties.The weight is different.How it handles goingup a hill is differentbut the point is that when these two carsare driving at the same speed,the accelerometer data is different.Like right now, I can seemajor changes in frequency.I can feel the bumps.- Now, automotive manufacturershave a whole departmentdedicated to these vibration.It's called the NVH departmentor noise, vibration andharshness, which coincidentally,is also the name ofNolan's new metal band.(rock music playing)It's the NVH department's jobto eliminate rattles and shakes in the carbut also define how theharmonics of the vehiclemight amplify vibrations.So for the perfect consumer car,the NVH department wants to build a carthat feels comfortable at any speed,which means it's gonna feelslower and more controllable.But for a sports car,they might tune up that sensation of speedto give the driver that thrillof a quick car at any speedand this can be done in a couple of ways.You can do it with a louder exhaustor piping in induction noises,or simply putting an Nbadge on the back of it.Now as you look out of yourwindshield at the road,you may think you knowwhat speed you're goingbut how much can you actually trustwhat your eyes are telling your brain?A study published by Harvardshows just how wrong your eyes can be.So they did an experimentand the test took 30 people,showed them 200 different videosfrom a driver's seat perspectiveand asked to estimate thespeed the car was going.The results were that the widerthe video's field of view was,the more off theestimations of speed were.The more context youhave for where you areand where the things around you are,the slower you are goingto think you're going.Take a look at thisvideo of a long hallwayand cover the center of it.Immediately, the edges looklike they are going fasterand that's because yourbrain has less timeto process the information,so it thinks the video is sped up.Now when we cover the edges of the video,your brain can processthat information quicker,so it feels like thevideo is played slower.But peripheral vision isn't the only waywe can affect perception.Many people say thatlower cars feel fasterand in a 2004 study, theTransportation Research Boardset out to test that exact theory.They found that when askedto drive a comfortable speedin a simulator, driversat a higher ride heightwere consistently going faster.Not only that but 56% of the driversthought they were going fasterin a lower ride height simulationwhile actually going about4 mph slower on average.But vision is only one sensethat is giving your braininformation on speedand we wanted to find outif we took away your visionand we took away your ability to hear,is your body able to tellany differences in speed?Then Joey's gonna drive me aroundbut I'm not gonna have anyauditory or visual senses.I'm gonna put these earplugs in,I'm gonna put somenoise-canceling headphones onand I'm gonna cover myeyes with this mask.We're gonna go for a little,little loop here in Mulholland Driveand Joey's gonna tap meand I'm going to have to tell himwhat speed we're going tothe best of my ability.Let's see how good my butt-dyno is.Uh, probably going 30.- 35.- Uh, 35.- 44.- Uh, 58.- 75.What?!Uh, 42.- 45, still really close.- Uh, 62.- 69.- Uh, 58.- 58, okay, there we go!- So was I worse or better?- You were just more accurate overall,which is really interesting.So, like, my first thought is that this iscloser in drivecharacteristics to your F150.It's a car for comfort.The suspension's gonna like,be, not similar, but closer than the FRSand the FRS is just an unknownquantity to your brain.You know?- I will inherently knowlike if you're shifting upor down and then the revs go higher,that I'm increasing speed.- Yeah, so you're thinkingabout acceleration and stuff.- Right, so I think I'm liketrying to process too much information.- All the stuff thatyou're getting from the FRSnot under like, not knowingwhat speed you're going.It doesn't matter if you'reguessing higher or lower.The fact that you're offshows you're being overloaded by the data.- Right.So we can feel acceleration.And a car with stiff suspensioncan pass more acceleration to our bodies.Most of that accelerationdoesn't feel like speed.It feels like bumps,but some of it can bemisinterpreted by the brain.These quick changes inacceleration are known as jerkand jerk might be responsiblefor some of that sensation of speed.And I say might 'causeeverybody's past experiencecan influence this feeling.Some smaller events ofacceleration and jerkthat your mind doesn't havecontext for can trick it.That's jerk that comes fromthe vibration of the engine, for example,or rumble in the exhaust.Beginning race car driversexperience this all the time.The body panics, the informationis coming at you too fast,so you slow down to be able to cope.The car can actually gofaster but you can't yet.So to become a faster driver,they practice reducingthe sensation of speed.And part of that comesfrom knowing the trackand knowing the car,so the driver's braindoesn't have to processas much new information in the moment.Well, hold on, wait a second.Hold on.Wouldn't you want to panic?Wouldn't adrenaline help you go faster?Let's imagine I give you a digital watchthat is flashing random numbers.Now imagine if we sped up that watchright up to the point thatyou can't read the numbersand it's just a blur.Right at the edge of what your brainand your eyes can handle.Then imagine I pushed you offa building with a bungee cord,well that's exactly what someexperimental scientists didat Baylor at UT.They had test subjects tryand read the flashing numbersas they were dropped from a bungee line.And guess what?They couldn't read any of the numbers.It turns out that adrenalinedoesn't make you act faster in the moment.It does not increase the speedat which your eyes and braincan handle information.For a driver, the onlyway to slow down timeis to have less new information.The more information you havefrom experience or muscle memory,the more brain power youcan dedicate to the track.But you can go too far.A driver still needs informationto know what's going on.With no info,your brain might be ableto handle going fasterbut it's not equipped tokeep you on the track anymoreand pretty soon, you'll outdrive the car.So on a track I'd rather be drivinga slow communicative carthan a fast numb one.But in road cars, we don'tneed all of that information.We don't want to be bombardedwith race car noises and vibration.So there's plenty of thingsthat affect a car's feeland feeling fast mightactually slow you down.I think we just accidentally proventhat a loud exhaust, cutsprings, and limo tint,will make you less likely to speed.Thanks to my field correspondent Joey,we're going to be using Joeya lot more in our episodesof Bumper 2 Bumper.We're gonna be branching out.We're gonna be doing a lot more tests.A lot more actual physical science.So I hope that's what you guys like.If you do, leave a comment,hit me up on Instagramat Jeremiah Burton.Hit us up at Donut onInstagram at Donut Media.Till next week, bye for now.