Inside the Solar Car Challenge with Dr. Lehman Marks - High School engineering!

Inside the Solar Car Challenge with Dr. Lehman Marks - High School engineering! In Wheel Time Podcast: Your Go-To Automotive Talk Show · Jul 11, 2023

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Welcome to another In Wheel Time Podcast, a 30 minute mini version of the In Wheel Time Car Show that airs live every Saturday morning 8 to 11am central.

It's the In Wheel Time Car Talk Show Coming up.

We're going to talk to Dr Lehman Marks with Solar Cars and the Solar Car Challenge.

We've got that coming up.

Later we're going to have some of the stories making automotive news headlines this week And right off the top here we're going to talk to Conrad about the Events Calendar Not the Cruisin Calendar, but the Events Calendar.

He gets those mixed up sometimes, so howdy howdy, along with Mike out of this World, mars King Conrad DeLong.

We always need more.

Jeff Zeke and I'm Don Armstrong.

Thanks for joining us on this Saturday on our live broadcast here.

We really appreciate you.

Our own version of what was.

Kardashians Doc.

Soup.

What was Paul Lind?

Paul Lind.

Hollywood Squares.

From Hollywood Squares.

That guy was The center square.

He was out of control.

But so fun.

Yes, most definitely.

Okay, so as we wait on our Solar Production Car Magnate, mr Lehman Marks, we're going to talk about the events calendar stuff that's coming up.

So next weekend is the Texas Road to Revolution cruise, starting at the Black Bear Diner in Humble, texas, and they're going to head out of there about eight o'clock in the morning.

That's a cruise, not a cruise in Right, and they're going to cruise through East Texas, the Piney Woods and stuff.

Man, that sounds good.

It should be a fun little drive.

And then a Saturday, october 8th, octurbofest Oh, octurbofest in Waco, texas.

That's a play on words.

It's a good play on words.

You know, everybody's always looking for their creative way to call what they're doing automotive OCTURBOFEST.

And that's at Kareem Shriners Hall in Waco, texas, on the 28th, from 12 to 5 pm.

Do you hear that George?

George is definitely a Waco.

I'm skipping.

A George is on Just down the road from you.

Yep, just don't skip it.

Anyway, go ahead.

That's it Back to you, Don.

Oh, thank you very much.

All right, high Schooler is going to be taken off next week for the 2023 solar car challenge and joining us now is Dr Lehmann Marks And he's kind of heading the thing up.

Good morning, dr Marks.

Good morning everyone.

How are you?

Well, we're very good.

Thank you, it's a little hot here in Houston, texas.

Where are you located?

Well, I'm in Plano And I actually have six of my interns working with me this morning to load trailers in preparation for the race.

So they're sort of delighted that I have a chance to get off and visit with you guys because they can sit down and rest a bit.

So a lot of people are favored this morning.

Yeah Well listen.

I know that it's going to be hot up there in Plano as well, but in the meantime you got another hot topic coming up in the solar car challenge.

Explain to everybody what exactly that entails.

The solar car challenge is a top level project based STEM initiative designed to motivate kids in science and engineering and alternative energy, and we do this by teaching them how to build a road worthy solar car.

I mean, what is it like to go to a kid and say, hey, don't you want to build a car, don't you want to power it by the sun, don't you want to drive it at a world class NASCAR facility or go cross country?

That's what we're doing this summer.

We're going from Fort Worth on the 16th to Palmdale, california, getting there on the 25th.

I think I should have some stickers put on the car saying California a bus like the old days.

You're the only people that are headed towards California.

Everybody else is headed out of California.

Maybe we should have started it in California and brought them all to Texas, because they're moving here anyway.

Well, let me add that it's yeah, they're building cars, but what we're doing is we're building young engineers and scientists.

That is our goal.

We've seen technology improve over the 30 years that we've been doing this, but every year we get a whole fresh batch of new kids.

Yeah, and I get to see the excitement that they have from this learning, commitment and dedication, and they have some successes and some failures, but they learn to pick themselves back up again And that's huge.

That makes a big difference in life.

Well, I will tell you.

I will tell you this My youngest daughter, who's now 30, she's an astrophysicist and she got going early on in high school and the STEM thing And she was headed into the robotics thing and they won the state championship and all of that sort of stuff.

So I take great pride in the fact that she was inspired by her teacher there in high school And you seem like one of those kind of guys that everybody wants to be in your class and use your expertise and guidance and making such a great thing.

Impact.

Yeah, And an actual car.

Are you working on one car?

Are you working on several cars?

How does it?

How does your program work?

We have 261 teams in 38 states.

Wow.

It started off this year with 100 schools trying to build and get ready for the summer's race 22 registered.

I suspect we'll end up with 18 cars on the race because they won't all pass qualifying.

There's not a kit.

We have an extensive set of guidelines.

We bring the kids in, the teachers in and we do instructional workshops And then we do mentoring and onsite visits and we have all kinds of virtual things And we teach them that there's no one solution to a problem And that sort of excites them because they look at the other cars and they say, well, i could do that, or I can do better than that, or hey, we need to bootstrap up our car.

So they'll be.

Should be 18 cars going with this cross country.

Now do you have are you in charge.

Are you in charge of all 18 22 teams or do you have a team that you've entered yourself?

I have 46 volunteers who work with me to make this happen.

Wow.

I got you.

We're actually have eight vehicles ourselves that are going along to make sure that everything's okay.

We have an advanced team that goes out about two or three hours ahead of the race.

We have vans for extra judges, we have a security team, we have an emergency medical group.

We have a truck carrying 450 cases of water for everybody, so we take good care of them.

Chase, Chase vehicles.

Impressed me is that the towns this year really are excited to see us come back.

Every town that we go through Snyder, texas, carlsbad, el Paso, florence, arizona, phoenix, wickenburg, 29, palms and Palmdale they all are so excited that we're going to be there And we like it because, yeah, the kids get to show off things but we get to inspire.

I think that's one of the best things we do.

We're going to pass about 200,000 kids along the way And, if you've got a moment for a story, we were doing a race to New York in 2007, pulled out onto this grassy field and the drivers were getting out of the car and they were mobbed by eight or 900 kids who went up and were just touching them.

Touching them sort of like the film Close Encounters of the Third Kind Yes, when all the aliens come out and they start manhandling Richard Dreyfus and get him up there.

Well, they were doing that And I went over to one of these kids and I said why are you doing this?

And this young kid maybe 10 or 11, looked at me and he said because they're astronauts.

And it dawned on me that what we were really doing was yeah, we helped the kids who were taking part in the project, but we're creating dreams in the minds of the all the kids, kids of all ages who see us along the way.

So that's one of our missions.

I wonder where that nine or 10 year old is today If they found a program that they can get involved in in their local area, right?

I don't know, but we've had a number of them.

We've had a number of teams from Illinois that were right around there.

So maybe, so I would like to think that would be the case.

Now are you a doctor of education.

Say again Are you a doctor of education?

No, i'm a doctor of law.

I have taught law school, but I've also taught sciences for the 30 years too, and engineering, and I just enjoy working with young people.

But no, my doctorate in law.

Interesting.

So what are one of these cars look like?

Oh, they're exciting.

Everybody looks a little bit different.

The newer teams, who are using less expensive solar cells and less expensive motors generally, will build a carriage with the solar car above them so that they can enjoy the shade, and when you do that, then you don't have to worry about controlling the power.

It's all on one level and you can easily control it with a power tracker.

As they become more advanced, then these teams start taking on some really sophisticated aerodynamic configurations, looking very much like the college and corporate vehicles that are taking part in the world solar challenge in Australia in October, and we're talking about some really sleet things I wish I had.

If you can see behind me in my picture here, some of these cars this is from a preceding race and they all look a little bit different, but as the team develops over a few years, then they really want to become more aerodynamic.

Let's look at the surface of the solar cells.

Are they all pretty much standardized for these kids So?

it depends on what they can afford.

We teach the kids how to develop a plan, a budget, how to fundraise, and, based upon what they can raise is sort of what they can spend on the solar cells.

Today, with the technology, our most basic teams are running about 22% efficiency or less.

You can add a more efficient solar cell, but it's about four times the price and that will take you up to 24 or 25% efficiency.

So really the gain is not all that great, but I guess it gives you a little bit of an advantage.

Right, they all pretty much have about the same area of solar coverage they can do.

So.

It's how efficient you make your car, how much you are able to use that energy coming in, how to use it wisely.

They call solar car driving the brain sport, and the reason for that is the driver should have the least to do with how the cars run.

You should have a chase vehicle that has a strategy team that's able to get information from the car by telemetry and they know how much sun's coming in, they know how much the motor is pulling out of the batteries to run the car and they can then, using their statistics, tell the driver how fast to drive.

And then they also should be aware of the weather up ahead, so they know if you've got clouds, then go fast until you find the sun And then, when you've got the sun, slow down so that you can be able to get your batteries recharged.

You indicated it as a race.

Now is it a race for just completing the travel, or is it for speed as well?

Is it time and distance scored?

The teams that accuse the most miles over the eight days of the race are declared winners.

Oh, and we have five divisions, so in the classic division you could be a winner.

The advanced classic, the advanced.

We have a electric, solar powered division and our new cruiser division this year that holds four people.

Wow, a pardon, that's going to be interesting to see going cross country.

So are the teams allowed to get sponsorship to support the cost of building the car.

Absolutely.

We want them to because, as a byproduct of this program, we want the kids to learn how to talk about it.

My philosophy is if you can't talk about it, you shouldn't be doing it, and learn the business side of it.

You can learn how to stick out your hand, shake somebody's hand, look them square on the eye and say I need your support.

Yeah, i need $5,000.

Or more.

Well, i was an engineer at General Motors and I remember way back you would mention the World Challenge and I think GM won the first one with that for lack of a better phrase a cockroach looking solar powered vehicle.

I remember that, yeah.

And I remember talking to a couple of the people that were involved in it and they said it's as much about rolling and wind resistance as it is about solar, because the solar generates the power, but the power is needed to overcome the rolling resistance of the vehicle and the wind resistance of the vehicle as well.

So you got to find that balance of how much power do you burn and how can you reserve it, because your rolling resistance is so low.

So there's a lot of physics engineering that comes into this besides just the solar engineering part of it Absolutely.

That's why in our workshops we teach mechanical engineering and electrical engineering and battery technology and aerodynamics.

We spent a lot of time talking about rolling resistance and how you reduce that resistance from the airflow going across your car.

Now, of course, if you're a brand new team, you're just lucky to be able to get things put together.

But then they begin to realize this could be more sophisticated and you get some teams doing some really remarkable things.

But they learned the good science in it.

You're right, the physics in this is really important And I guess you might say one of the reasons why I started this thing was that I found that my kids in classrooms couldn't relate to what they were learning in the textbooks.

So if I could give them something to do with a hands-on then it would make a huge difference.

So some friends at the University of North Texas in Denton was building a solar car in 1990, and they invited us up to come see it.

So I took seven kids up there and all the way back to Dallas they kept on saying can't we build a car?

Can't we build a car Now?

there were no high school solar cars then.

So, my wife says this was the worst decision I ever made.

I turned around and said OK, we're going to build a solar car.

So we followed the at that time they called it the sunrace and that was sponsored by GM and the US Department of Energy.

It went from Arlington, texas, to Minneapolis And we realized that there's no way that high schools were going to be able to compete with colleges or with big corporations.

So that's why we started our education program in 1993.

And we had our first national event in 1995, only three cars in the first event one from California Irvine, california, one from Missouri and one from Dallas.

Since then we've worked with now about 75,000 kids.

Wow.

And these are kids like 16, 17 years old Boys and girls, right, right, interestingly 48% girls, 52% boys and we are so balanced with the kids taking part here.

I've got some great stats.

If you want to hear it, yeah, we do, ok.

White, 35%, blacks, 19%, Hispanic, 28%, asian, 12%, native American, 6%.

Wow.

It didn't get much better than that.

Yeah, no, good cross section.

Oh, you hear my critic.

here is my Doug Seney How many canines, no canines.

Well, he actually is the official dog of the race and he goes with me And when the kids are having problems he sort of soothes them a little bit.

I got you, he's the therapy dog, that's right, that's right.

So I assume that there's going to be some sort of internet coverage and I'm just guessing Probably get news coverage, but that's spotty, to say the least.

But how can we follow?

How can we follow you online If you go to our web page, wwwand the long word solarcarchallengeorg, then we will have a A link on there, on our web page, where you can see in real time where all the cars are.

Each judge, each team has a judge, each judge has a GPS system So we know where the judge is, we know where the solar car is And so we can keep track of the cars that way and you can see the progress And each day the results are posted on our events results link.

So our web page, solarcarchallengeorg, is a post of information for you.

Yeah, I've already posted that on our social media.

So you said there's a qualifying portion of this that they have to qualify.

What is the qualifying entail?

Beginning on the Thursday July, the 13th, 13th, 14th, 15th the cars will qualify.

They have to go through seven stations.

First off, they go through a mechanical check to make sure that they followed the very specific guidelines for safety and building the car.

Station two is electrical, where we make sure that the electrics are fine and that everything's going to work right and everything's protected and properly.

No fear of a thermal event, that's right.

That's right.

Third is a tilt and turn.

We want to raise the cars up 30 percent, see if anything falls off.

And, seriously, it used to be an old bumper sticker that said, if you see nuts and bolts on the road, then you know that a solar car has gone this way.

Anyway, in station three that we determined, can they make the proper turning radius so they could get through turns in the community?

Station four is slalom.

That's where we check out the drivers.

Can they handle the car?

Can they do, is the car capable of doing a slalom course?

Station five is braking.

We find out whether or not their brakes will hold and they have to meet a criteria for safety.

Station six is for stamina and endurance.

And can they load and unload the car on a trailer which you have to take.

And then station seven, our last station.

we have a big box truck and the car has to drive past it to see if it handles the vortices created by the the truck going by, so that they won't flip from wind current.

I would have the braking first.

So is there what's kind of the average weight of each of these vehicles?

If you're a top level car, you should be around 400 pounds.

That's not what the difference is.

If you are on the upper end, you might be as much as 1,100 pounds.

Does that include driver?

No, but some of these teams, particularly the new teams, want to use big wheels which are very weighty, maybe not able to do lithium ion phosphate batteries still using lead acid, all those kind of things.

That's a lot of weight It is And they've all got about the same amount of energy they're taking in.

But that's what you were saying.

One of the things you learn is you've got to take the car with that amount of energy and learn how to use it the best you can, and that means reducing the weight and reducing the rolling resistance and improving the aerodynamics.

So that's why the Brainsport Solar Car Racing really does so much for the kids.

Bringing all these factors together, Are these hard rubber tires?

It depends.

If you have the money and you can buy some sophisticated MIT type of wheels at $600 apiece, you're going to have a soft tire.

The cars with less money, they may be using motorcycle tires, so the advantage is the motorcycle tire is probably not going to go flat.

Some of the softer tires, you can be off the side of the road changing tires.

Got you, got you.

All that depends upon alignment.

Yeah, And the kids learn about the importance of aligning a car, making sure that you're steering as such that you're going to reduce the kind of friction with your steering.

So is the braking system that they use?

is it just a pure mechanical hydraulic system, Or are they using regenerative braking so that they can use the force of braking to recharge?

They can do regenerative, but we require two separate braking systems, not regenerative, which will generally be hydraulic, some would use mechanical.

The reason why we have two separate systems, two separate pedals on the floor on this is an experience that happened with one of my early teens.

We were doing a race in New York City, in Battery Park in 1994.

And the driver said the judge said to the driver I want you to drive as fast as you can and hit your brake And let's see how fast you can stop.

So my driver hit the pedal and went as fast as he could hit the brake.

The weld that was holding the brake in broke And I could see the calipers flying past the driver's head out through the front windshield of the car.

Oh boy.

Heading for the Staten Island ferry there at the end of Battery Park.

That's right.

And here are 15 of my students running after that car as fast as they could.

So that's why we have two separate independent braking systems.

How cool, in case one breaks the other and you say, well, why do this?

It's student built.

Yeah, that's right, So people you want to work out?

What a great idea.

Well, Dr Marks, it's great to talk to you.

We really wish you the best of luck in this year's Solar Car Challenge And again for more information, go to solarcarchallengeorg.

It's a pleasure to talk to you.

Best of luck, And let's check it again soon.

I appreciate y'all and your interest in this and great questions.

Thank you.

Thank you, sir, we appreciate you.

How fun Mike.

Mike, we had a dentist on?

We had a doctor on.

Can you get a psychologist next week and maybe round that out?

Call my daughter.

There you go.

Yeah, call Amy.

All right.

A couple of headlines First of all.

Let's do some.

Let's do some recalls, shall we All right?

Lincoln Nautilus for 2023, rear shock absorbers manufactured incorrectly.

Oh, Somebody didn't do their home.

Can we take a look at that before they put it on the car?

It goes sideways, not up and down.

Loss of power or fire from damaged control module on the Ford Fusion 2019 through 2020.

Yeah, Kat, that's 13.

13.

I'm sorry, Kat, this is a 13.

A 13,.

Okay.

Improperly manufactured battery charging unit on the BMW 760i i4 and the iX.

Ai-ai-ai.

Thank you, porsche Makens and Porsche Panameras beginning in 2016 through 2020,.

the seat belt anchor may detach from the seat.

Oops, that's not good.

Loss of power drive Power.

Loss of drive power from the fuel pump shutdown.

I'm not exactly sure what that means, but Mercedes Benz, and look look at the.

Can you see that?

Oh wow, can you see, the list.

It's a whole page.

All of them, pretty much all of them, from the 2021 through the 2023 model years.

So if you own a Mercedes Benz or a Mercedes Maybach, you might want to go to safercardgov put in the uh put in the van of that, half a million.

Well, I could suggest maybe trading it in on a Cadillac.

That would be my suggestion.

Yeah, cause Cadillac doesn't have any recalls.

Oh no, oh no, porsche 911 GT3 being recalled for incorrect activation of brake lights, hmm, Okay, that's the freak, the guy out behind you that's following.

Yeah, yeah, never mind, never mind The front.

Yeah, so sorry, never mind, it's not us, we didn't do it.

Ford Bronco has been nipping at the heels of the Jeep Wrangler, it's chief rival in the adventure seeking class of utility vehicles, and a regulatory ripple effect could tighten that race even further.

Us sales of the Bronco rose 38% in the first quarter to 32,000, while Wrangler volume fell 17% to 37,971.

Ford's gains could accelerate after Stalantis recently changed how it allocates.

Wrangler is in the 14 states that follow emissions guidelines set by the California Air Resources Board that are stricter than nationwide standards.

The conventional gasoline only Wrangler isn't being allocated for dealerships to stock in carb states, though the automaker said customers can still order them.

Dealers continue to get allocations of the Wrangler 4xE plug-in hybrid in those states.

Industry observers say the allocation method could leave an opening for the Bronco.

Potential Wrangler buyers in carb states who want the conventional gasoline version will be forced to make a decision.

Wait for an order.

Drive across the state line to Nevada.

Wait for an order, or head to a nearby Ford dealership and drive a Bronco off the lot the same day, while diehard Jeep enthusiasts are unlikely to switch brands and won't mind exercising little patience until their new Wrangler is shipped and let's say there's a chance those on the fence could be swayed if they need to wait.

Get a similar story not long ago about it.

Exactly, a quick break now we'll be right back here on the In-Wheel Time Car Talk Show.

Stay with us.

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a celebration at Loopy Tortilla.

Loopy Tortilla founder Stan Hold and his wife Sheila are winning racers on the NHRA drag racing circuit and have a collection of hot rods and classics that everyone appreciates.

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The day will be announced soon and will once again be held at the Loopy Tortilla Tex-Max on 99 in Kingsland Boulevard, just south of I-10 in Katie.

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About this episode

Dr. Lehman Marks discusses the Solar Car Challenge, a unique STEM initiative that engages high school students in building solar-powered vehicles. With 261 teams from 38 states, the challenge aims to inspire young engineers and scientists through hands-on experience. Dr. Marks shares insights on the design, engineering, and teamwork involved in creating these cars, as well as the excitement of racing from Texas to California. The episode highlights the educational impact of the program and the importance of fostering innovation and problem-solving skills in students.

BMW 7 Series Ford Bronco Ford Fusion Jeep Wrangler Lincoln Nautilus Porsche 911 Porsche Panamera Renault Wind

Original notes

Ever dreamed of harnessing the sun's energy to power your ride? Join us as we chat with Dr. Lehman Marks, guiding light behind the Solar Car Challenge. This STEM initiative emboldens kids to design solar-powered, road-worthy cars. With a whopping 261 teams across 38 states, the race is heating up for the ultimate summer showdown.

From the solar cells used, to the physics that pave the way, Dr. Marks emphasizes a holistic experience, where kids learn not just the nuts and bolts of car construction, but also pick up invaluable skills such as fundraising and securing sponsorships. We also look at the diverse divisions of the Solar Car Challenge and how they encourage teams to search for sponsorships to fund their projects. There is also an understanding of the science behind solar-powered cruising, and the immense significance of reducing resistance to maximize collected energy efficiency.

But how does a car qualify for the Solar Car Challenge? What safety measures are in place? Dr. Marks spills the beans on the qualifying process, from mechanical and electrical checks to slalom and braking tests. Learn about the physics that play a role in determining the average weight of the cars and the different types of braking systems employed for safety.

Finally, we wind up with a low-down on the widely accessible In Wheel Time Car Talk show that hosts a live show every Saturday and offers a 30-minute episode on yoiur favorite podcast provider.

Join the In Wheel Time Car Talk family for a ride into the world of solar-powered cars.

Be sure to subscribe for more In Wheel Time Car Talk!

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