>> ♪ We'’’ve got two days to get this straight ♪ We'’’ve got a challenge just won'’’t wait ♪ Our eyes are on the prize ♪ An engineer just set the date ♪ We'’’ve got this client can'’’t be late ♪ Oh, no it'’’s go time ♪ Build it, test, fix it debug now and kick it ♪ Got to get it off the ground yeah ♪ Stick around and you'’’ll see what teamwork'’’s supposed to mean ♪ It'’’s so key Design Squad ♪ Design Squad.

♪ >> Oh, let'’’s just call it and go meet today'’’s client.

>> (growling) >> All right, guys, gather round.

>> Whoa!

>> Hi, I'’’m Kerri Morgan, and I play wheelchair rugby.

>> Wow.

>> I'’’m the first female ever to try out for the Paralympic wheelchair rugby team.

Wheelchair rugby is played on a basketball court.

It'’’s kind of like bumper cars for wheelchairs.

The game of wheelchair rugby is coed.

So I have men over 200 pounds on the court hitting me.

My game plan is to avoid them.

Oh, boy.

So it'’’s important that I work on my offensive moves.

That'’’s where you come in, Design Squads.

I want you to build me an automated wheelchair that will attack me.

It must track my moves on the court and simulate the hit of a defensive player.

I will test both chairs and keep the winning one as my training buddy.

Good luck, Design Squads.

Don'’’t blow it.

>> Nice ending.

>> What do you guys think?

>> Wow.

>> Intense.

>> All right, let'’’s recap the specs.

You guys are building an automated defensive wheelchair that'’’s actually going to track Kerri'’’s chair and crash into it.

Now, to help you out, we'’’re giving you two wheelchairs-- one you'’’ll modify, one you won'’’t.

You guys ready to do this?

>> Yeah!

>> All right, let'’’s go start brainstorming.

>> Purple Team, ready for this?

Let'’’s do it.

>> Oh, look at these.

>> Wow.

>> Whoa.

This is cool.

>> We'’’ve got our motors here.

>> Those things are strong.

Feel that.

They are so strong.

This is the transmitter, and here'’’s the receiver.

>> Infrared, right?

>> Yeah, infrared.

>> The infrared tracking system has two components-- a beacon and a receiver.

The beacon is a ring of infrared light emitting diodes, or LEDs, that send out digital pulses of invisible light in all directions.

The receiver has two sensors.

If a sensor detects the beacon to the right, it triggers the left wheel to spin, so the chair turns right.

If the beacon is on the left, the other sensor picks up the signal and triggers the right wheel to spin, so the chair turns left.

If the beacon is directly in front, both sensors pick up the signal, triggering both wheels to spin, so the chair moves straight ahead.

>> I guess this one is the one we modify.

>> Right, we change this one, and it hits this one.

>> Any ideas?

>> Well, the important thing is that it'’’s able to track her, and that'’’s able to collide.

>> Okay.

>> Because if that doesn'’’t work, than nothing else matters.

And then we get the motors going.

That'’’s the other thing.

The motors are what really give us force.

The chair can'’’t be slow.

>> It'’’s really hard to maneuver them.

So it'’’s not like they'’’re going to be going really fast all around.

>> Well, she'’’s an Olympic rugby player, and we'’’re not.

That'’’s just one difference.

>> There'’’s, like, ten billion ways to connect a motor to these wheels.

>> Yeah.

>> But because of our time constraint, the easiest one I can think of is this-- if we can get these motors somehow right here, this motor spinning would cause this thing to spin.

>> I like that idea.

>> What'’’s going to hold this heavy motor up?

>> That'’’s what I want to work on right now.

>> You can add the motors, bolt it through here like that, bolt it right through.

What do you think?

>> I wholeheartedly agree.

>> Cool.

What'’’s up?

>> It sounds good.

>> If you need any support emotionally, I'’’m right here, man.

You got my number.

>> Let'’’s go.

>> Okay.

>> Zach and Juan are working together really well.

Sometimes they leave me out of it, because they'’’re both guys.

It'’’s sometimes a little bit irritating.

>> I think we have two options for how we'’’re mounting our motors.

We can have them run directly on the ground as their own tire and just have the rest of the wheels free spin, or we can have them cause the big wheels to spin.

>> I think on the ground is the best.

>> So maybe we should mount it to the ground.

>> Yeah.

>> I was thinking somewhere like just in here.

If we could get it to attach to this pole, that'’’s really strong.

>> Lindsey, you think this is a good position right here?

>> Nice, Zach.

>> What'’’s up?

>> He drilled the hole a little bit too low.

>> So he'’’s going to just make the whole of it bigger on the top.

>> Just don'’’t make the same mistake on the other side.

>> Why do you sound angry when you'’’re saying that?

>> I'’’m just reminding you not to make so many mistakes, because we don'’’t have time to fix all those.

>> I'’’ve made one mistake.

>> Zach, she'’’s reminding you.

>> I'’’m just saying, time is a big thing here.

>> Reminding you in a very angry... >> Okay, I got it, guys.

>> Hold it steady, Juan.

>> Yeah, I was just upset.

I mean, because, like, it was my mistake, I definitely made an error in measurement.

>> Zach kind of messed up on this one thing, and... >> And Juan'’’s just so cocky, like he never makes a mistake or anything.

And he yells at you or freaks out at you when you make a mistake.

>> It'’’s not like we gave him a hard time.

Lindsey and I were just trying to be supportive.

>> It'’’s just so annoying.

It'’’s just frustrating.

>> Think we should mount the wheels to the ground?

>> Yeah.

>> We want the motors to be perfectly parallel, right?

>> Yeah, yeah.

>> So what we can do is... can you pass me the other motor?

>> Yeah.

On this cross, I'’’m just securing them on top like that.

>> And then we can hook this up to... >> Just go across.

>> Yeah.

>> This has to be so firm, and if this can wiggle back and forth, it'’’s going to wiggle back and forth, and I don'’’t want any grinding.

>> What do you guys think if instead of using this round shaft we can use maybe sheet metal to make it flat?

>> Yeah, because then you can attach it to all four points, and it'’’ll be a lot stronger, rather than just attaching it to two.

>> Yeah.

>> Yeah, definitely.

>> Yeah, getting there.

>> No.

So close.

It'’’s done.

>> Wait, dude, you'’’re done?

>> All I'’’ve got to do is inflate the battery a little bit.

>> Inflate the what?

>> Inflate the tire.

>> Yeah, we'’’ve got holes.

Is that strong enough?

>> Yeah, it'’’s really strong.

>> Great.

>> Sweet.

>> This is going to go in like this.

>> That looks really good over there.

>> Yeah.

>> Oh, good job.

>> It would be really cool if we could almost get this thing mounted today.

>> Yeah, that would be awesome.

>> Put your tools down, Design Squads.

That'’’s it for day one.

>> We did really well today.

I am really excited for tomorrow.

>> Purple Love.

Oh, sweat!

Eww, there'’’s sweat everywhere.

>> Folks, we need to bring a little more high speed to the table.

So this is a race.

A very important race.

We'’’re doing a wheelchair basketball slam-dunk relay.

The plan is, you take the ball, in the wheelchair, you go all the way down to the end, slam-dunk the ball through the basket.

After the slam-dunk, you go around the post, come back to the line, and you switch drivers and repeat the process.

First team to get all three drivers through with a successful slam-dunk wins the game.

The winning team will decide the stakes.

You'’’ve got all day to think about it.

Make them high and make them intense.

You guys want to win.

Do I have any questions?

>> No.

>> No.

>> Are we ready to go?

>> Yeah!

>> Got this.

>> On your mark, set, go!

>> Get out of my way!

>> Go Green, go Purple.

Come on, I want a clean game!

Oh, she'’’s doing a style spin!

You'’’ve got to pick it up.

Green Team, you'’’re good.

Come on, Lindsey, you'’’ve got to complete the slam dunk.

Come on back.

Good tactics, good tactics.

All right, Lindsey, you'’’re good.

Little forward push there.

Come on.

All right, Wes versus Zach.

It'’’s crazy!

Oh, geez.

Green Team'’’s good!

Clean one.

Green Team is the winner!

>> Yes!

>> Nice job, Green Team.

Purple Team, good effort, good effort.

You guys have all day to think about what you'’’re going to have Purple Team do.

>> So we need both motors on.

You need to finish the circuit thing.

I'’’ll work on the bumper when you guys hook up everything.

>> Sounds good.

>> All right.

>> Juan, you want to test the motor?

>> Yeah.

>> Look at where they interact.

>> Yeah.

>> See how it kind of, like... See, right there, it'’’s not touching.

>> Yeah, yeah.

>> And then right there it is.

See if you can just lower it down a little bit more.

>> Yeah, I can do that.

>> Sure?

>> Yep.

>> You got some, you got some.

>> It'’’s on.

>> Okay?

>> It'’’s tight.

>> All contact.

Great.

Nice, Zach.

>> I want to get this thing going.

>> I know, we'’’ve got to get going.

>> We can just stick one bolt directly from here to the motor.

>> From where to where?

>> Drill a hole through this and just stick it directly to the motor.

>> Brilliant.

>> What'’’s up?

>> All right, I'’’m going to flatten this right here, and then I'’’ll bolt it to this, which is holding the wheel, and use the bender and wrap around this curvature.

And that way we'’’ll have a bigger bumper so that she can get rammed into.

>> Sounds good.

>> Left side looks pretty good.

>> Green Team, I'’’d like you to meet Kerri, your client.

>> Hi, Kerri.

>> Kerri, this is Green Team.

>> Nice to meet you guys.

How'’’s it going?

>> Good.

>> Very well.

We have the infrared transmitter, and this can go where it would be least in your way.

But we weren'’’t sure where that would be-- in the back... >> Try looking at the back.

So when I push, my elbows come back pretty far, so it'’’s going to kind of have to be more towards the middle, so it doesn'’’t interfere with arm movement.

Looks like you guys are on a good track.

You guys got any other questions?

>> We were thinking about modifying the bumper.

>> Really, the purpose of just having the fender is to protect that chair and keep it in one piece, so that it can deliver a force.

So you'’’re just going to need something, you know, strong and heavy duty so that when it rams into me it'’’s just going to keep that chair intact.

>> Great.

>> Thanks, Green Team.

Let'’’s go check out Purple.

>> All right.

>> They'’’re just right around there.

Purple Team, meet Kerri, your client.

>> Hi, guys.

>> I'’’m making a bumper right now, so this will have, like, two rods hitting you.

>> So how high are you mounting this piece right here?

Show me again where you'’’re... >> I'’’m going to attach it right here.

>> The height that you'’’re showing me would be illegal in rugby chairs, and it would come up and potentially hit my legs instead of my chair.

See where my bumper ends here?

You definitely don'’’t want to go any higher than that.

Does that kind of make sense?

>> Yeah.

>> Okay.

>> Anything else, Purple Team?

>> We got what we needed.

>> Keep going.

I'’’m excited to give it a try.

I'’’m building a bumper for the front.

>> Oh, you'’’re going to put this in the front?

>> Yeah.

>> Wouldn'’’t that be destructive, though?

>> No, because we can put foam around it.

So here maybe we can put, like, a wheel that will, like... you know, or maybe we can put... >> Is that for attacking her?

>> Yeah.

>> Or maybe we can put, like, a spring, right, and when... yeah.

>> Are these edges facing her?

>> Yeah.

>> We'’’re going to cover that in foam, so that doesn'’’t matter.

>> I think she wants a big surface to hit against, not little things to get caught on.

>> Yeah, like, this would get caught on her chair.

>> Yeah, you don'’’t want to accidentally flip her chair.

>> We have to think, like, outside the box.

>> Right, but we also have to think what'’’s practical that would help her train for rugby.

>> Annelise can be so controlling sometimes, and I don'’’t like people telling me what to do or how to do it.

It gets to a point where I can'’’t take it anymore, and this point is about now.

>> I mean, I understand that we want it to be more than a normal chair, and I think we can accomplish that by making the target bigger, but not by adding spikes and things that stick out.

I feel like I'’’ve said that before, and it hasn'’’t gotten through.

>> Ana, I think we'’’re going to take it off, because it'’’s a little dangerous having that on.

>> All right.

>> Annelise, sometimes you'’’ve got to go safe, but sometimes you also have to go outside the box.

And sometimes, like, you'’’ve got to listen to other people speaking.

Like, you know, I feel sometimes you don'’’t listen to me, and it'’’s seriously getting to me now that we'’’re, like, three hours away from the final.

>> Maybe we can think of a way that'’’s exciting and safe.

>> Check it out.

I'’’m going to make a template for the other one so that we know exactly where the holes go.

I'’’m going to put this motor here, and then I'’’m goingto put a piece of paper on here, draw the holes on a piece of paper, and then just wrap the piece of paper around and tape it down so we know exactly where the holes are.

>> Yeah, man, we should have done this the first time.

Keep it straight.

>> Nice.

>> Exactly.

>> Yeah.

>> Yeah.

>> Looks good.

>> Beautiful.

>> Nope, these are good.

>> Check it.

It'’’s done.

>> Give me a hug.

Give me a hug.

>> What'’’s up, are you finished?

>> Yeah.

>> All right, let'’’s go.

That was our five seconds of fun.

>> It'’’s pretty strong.

>> We want to make this, like, creepy and, like, aggressive.

So we'’’re thinking about doing something, like, with horns, and red, and fire.

>> Nice.

>> Let'’’s go see how this fits.

>> Oh, dude, I think you bent it a little bit too much.

It looks like the dentures of a really big robot.

That'’’s what I'’’m trying to say.

>> So much better than you, huh?

>> Don'’’t even, don'’’t even.

>> I think this is definitely better, and a lot lower than what we had before.

Hey, Juan, I finished.

>> "The Kerri Kruncher."

I don'’’t get it.

No, you lost me.

>> Oh, my god.

>> Are we still planning on mounting it on something up here?

>> Yes.

I should work on that.

>> Should we build that?

>> Can you wire it up now?

>> Yeah.

Here'’’s how our circuit'’’s going to work.

The power travels from the battery through our fuse.

>> Basically what a fuse does is it makes sure that the amount of current going through it is right.

If it gets too large, the fuse breaks, and it breaks the circuit.

>> And then through a special switch called the relay... >> The infrared receiver that we have works on very, very low current.

And the motors that we have work on very, very high current.

A relay controls high current, kind of like a protection for the receiver.

>> When the receiver receives an infrared signal from our beacon, then it will close our switch, causing the power to go to the motor, which is what turns our motor on.

>> Guys, we'’’re ready to test this.

Okay, Zach, I'’’m going to need you to walk with the receiver, or the terminal.

>> Sure.

I'’’m going to connect positive terminal.

>> Right, let'’’s test.

>> Nice.

If I'’’m over here with the beacon, that wheel'’’s going to propel the wheelchair toward me, turning it this way.

So that'’’s good.

Let'’’s try middle.

Now they'’’re both on.

It'’’s coming straight at me now.

Good.

Now I'’’m on this side, so just that one, and that one just off for the same reason.

Now it'’’s coming toward me.

>> Looks really good.

>> So good.

>> Okay, okay, dude, can you not touch me, man?

>> You ready?

>> Ready!

>> That thing went so fast.

>> Ow!

That was hard.

That'’’s good.

>> Oh, my god!

>> Bring this back.

Can we zipline his arms together?

>> Because his arms are hitting the wheels.

>> Cool!

>> All right, all right.

All right, guys, we'’’re ready to test.

>> That'’’s definitely working.

Definitely following you.

When you cut too fast, outside of the range, this guy'’’s range, you can'’’t... like, you stop.

Like right here, you cut too fast.

>> Yeah.

It did go toward the beacon, it'’’s just that the beacon'’’s behind you.

>> I think that we need to finalize how we'’’re going to attach the transmitter.

>> Yeah.

>> I hope you'’’re done, Design Squads, because day two is over.

>> All right!

>> Awesome job.

>> Way to go, Kerri!

>> Nice job.

>> Good to see you guys.

>> You, too.

>> Looks like you'’’ve got some fun stuff for me.

>> Yeah.

>> All right, Purple Team, you'’’re up first.

You'’’re going to have to rig the beacon onto Kerri'’’s chair.

>> Yep.

>> All right, Kerri, here'’’s our finished product for you.

>> Okay.

>> It'’’s about the same size, same weight, and it goes about the same speed as a real rugby player.

And it'’’s going to pack about as much of a punch, too.

>> All right, bring it on.

Let'’’s give it a try.

>> Okay.

>> Yeah.

>> All right.

>> Here it goes.

>> Kerri!

>> Kerri!

>> Oh!

>> Uh-oh, did I hurt him?

Oh, yeah, here we go.

Did I lose him?

>> That thing is nasty.

>> Come on, come on.

>> Go, go, go!

>> That'’’s the eeriest-looking thing.

This dummy all the way across the gym.

>> All right, Purple Team, I think I'’’ve seen enough.

I think I'’’m ready for the Green Team.

>> Nice.

>> Oh!

Look at it go!

>> The thing about theirs is they have their receiver, like, really high and in front.

I'’’m afraid that if she does hit it, like, head-on, it'’’s going to smack her in the face.

>> Oh, no!

>> What do you say?

Have you seen enough of both of them to judge?

>> I think I'’’ve seen enough.

>> So weighing them against each other, what would you say about each team'’’s chairs?

>> For the Green Team, the chair seemed to track me a little bit more.

It had a little bit more get up and go.

>> Ours definitely went a lot faster.

>> Yeah, it hit her really hard.

>> A little bit more kick to its punch when it hit me.

>> It'’’s all dented and disgusting now.

>> Battle scars.

>> The Purple Team, the way that they created the fender to give me an impact was a little bit better than Green Team'’’s.

>> I think we have a way better design.

>> She had ridiculous hits.

>> Yeah, man.

>> They designed it all the way around, they designed it a little bit lower, it took a better hit.

>> All right, Design Squads, Kerri has come to a decision.

Kerri?

>> All right, it was a tough one.

Overall, both chairs gave a really good impact.

It felt just like a rugby hit.

Purple Team, the fender that you designed, I could actually collide with this chair anywhere.

I didn'’’t have a fear of breaking anything.

And you also get the award for the best name of the chair.

I like the Kerri Kruncher.

Green Team, the way that your chair tracked me, it seemed to pick me up a little bit better.

The other, I think, really strong positive about your chair was that it was like rugby in that once it hit me it kept coming after me.

And I like that.

So overall I'’’m going to have to go with the Green Team.

Whoo!

Yeah.

>> 100 points goes to each member of Green Team.

Congratulations.

And if I'’’m not mistaken, I believe there'’’s one more score to settle... >> Uh-huh.

>> ...from the wheelchair rugby basketball relay challenge.

So?

>> Guys, your dare is that you have to dress up as girls for the beginning of next challenge.

>> I can'’’t find a double-zero here in Boston.

>> You guys are going to look great.

After two challenges, Ana and Wes are sitting pretty in the lead with 200 points.

>> Hey, Lindsey, there'’’s so much more action on our Web site.

>> Yeah, behind-the-scenes stuff like our blogs.

>> Not to mention you can watch full episodes.

>> Play games and build cool projects.

>> Awesome.

Let'’’s go to pbskidsgo.org.

Coming up... >> New Orleans, baby!

>> Design Squad to the rescue.

>> This is the best thing I'’’ve seen you guys build yet.

>> New Orleans, here we come!

Media Access Group at WGBH access.wgbh.org >> We are PBS.