The DTADS, or Dog Treat Airborne Delivery System (Catapult #2)

Ah, yes. The famous DTADS, or Dog Treat Airborne Delivery System. Famous in my house, at least.

I chose to build the DTADS as my second catapult for a fairly simple reason: my dog wanted a snack. Of course, I could’ve just tossed the pooch a few treats. I didn’t need to build a miniature siege engine and launch the things at him from across the house. But doing so was approximately 49 times more fun than feeding him the regular way, and if that’s not a good enough reason to do something, then I’m not sure what is.

This is his hungry face.

Like my first catapult, The Cotton Ball Blaster, the DTADS can be made using only a few, relatively easy-to-find materials. I made mine with just three things, all of which I happened to have lying around the house.



These thin strips of wood are called laths. They’re often used to make lattices, which are then placed along the bottoms of decks in order to keep out critters or set up in gardens in order to get plants to grow in the direction you want them to. I had a bunch of leftover laths from an old project, and as soon as I remembered they were down in the basement, busily collecting dust, I knew just how I could put them to use.

If you don’t have any laths, don’t worry. They can be purchased for cheap at a hardware store. And if you go to one of the really big hardware stores, you can even get them for free! How? Well, most of these stores either offer to cut your lumber for you or leave out the equipment you need to do so yourself. Around these areas, you’ll always find plastic bins, and unless someone has recently emptied them, these bins will be filled with the unwanted, cut-off ends of once much longer pieces of wood. Ask an employee if you can look through and take a few of these scraps off their hands, and unless they’re in a seriously grumpy mood, they should let you.

I knew the pieces of wood I had would be perfect for the two larger parts of my catapult – the base and the arm. The base is the part of the catapult that sits on the ground, anchoring it, and the arm is the part that gets bent back and released, launching whatever it’s got on it. But you can’t just lay the arm on top of the base. You need to separate one from the other using a fulcrum.

What’s a fulcrum?


In this situation, both of the definitions above apply. Because when it comes to the DTADS, the fulcrum is utterly essential. The fulcrum is the thing that turns a couple old pieces of wood into a machine capable of sending your dog’s treats soaring high up into the air, arcing across an entire room or hallway (that is, if it doesn’t slam into the ceiling before it gets there).

For my fulcrum, I decided to use this:


It’s a bouncy ball (a very bouncy one, in fact). But wait – there’s no need to tear apart your house looking for the bouncy ball you got at the dentist’s office that one time he told you, “You won’t feel a thing,” and then proceeded to drill actual holes into your teeth and yeah, maybe you didn’t actually feel all that much, but still it was uncomfortable and scary and I mean a bouncy ball, does that shiny-teethed lunatic really think a cheap little toy is going to erase the nightmarish experience he just put you through?!

Excuse me. Sorry.


What I’m trying to say is that you don’t need to use a bouncy ball for your fulcrum. You can use almost anything. A rock. A stack of quarters. A wad of duct tape. Some pieces of cardboard. A hunk of old, hard cheese. Some fulcrums will work better than others, but the only thing a DTADS fulcrum must do is lift the arm up off the base, and do so at an angle that allows it to be bent back and released.

Now that I had a base, an arm, and a fulcrum, I knew I needed only one more thing: something to attach these three parts together. Ideally, it’d be something strong, yet flexible – strong enough to hold everything together, yet flexible enough to allow the parts to move around a bit (like when the arm is bent back). Maybe you’ve already figured out what I came up with:


That’s right – a rubber band. A favorite material of the EngiNerds. You just never know when one of the things might come in handy.

And now all that’s left to do is assemble the DTADS, and that’s easy. You just have to place your fulcrum, and then bind everything together with your rubber band. But where, you might be asking, should the fulcrum go? The answer is anywhere. You’ll find, however, that certain positions allow for better launching. The ideal spot is somewhere between the middle and end of your base. You’ll have to do a little experimenting to find the perfect spot, as it’ll be different depending on the materials you use.


Et voila! As you know from the Cotton Ball Blaster post, that phrase is French for, “Now let’s go launch some stuff!” But did you know that in Hungarian it means, “Feeding your dog his own body weight in bacon-flavored treats may or may not lead to said dog vomiting on your nice white carpet?” Unfortunately, I didn’t either . . .

Now go do some launching!

I will be! (Once this carpet’s clean.)

. . .

And now for the rundown:

Name: The DTADS, or Dog Treat Airborne Delivery System

Difficulty: if you can operate a rubber band, you’ve got this

Cost: minimal – you can surely find that rubber band and something to use as a fulcrum, and if you don’t have anything to use for a base and an arm, you can get those materials cheap (or for free!) at your local hardware store

Uses: feeding your dog from afar; feeding your cat from afar; making your carpets “bacon-flavored”

The Cotton Ball Blaster (Catapult #1)

If you’ve been keeping up with the past couple weeks’ worth of EngiNerds-related posts, then you know the first book in the group’s epic adventure involves catapults. In celebration of EgniNerds’s release on September 12th, I’ve decided to channel my own inner EngiNerd (not too tough a task) and build a few catapults myself.

For my first catapult, I figured I’d start easy. Really easy. This first, most basic of launchers requires only THREE things:

  1. an “arm” (the part of the catapult that you bend back and release to let fling forward)
  2. a “bucket” (the part at the far end of the arm where you put the to-be-flung object)
  3. something to help attach the bucket to the arm

It took me only two minutes to find these three items around my house, and I’m 99.9% sure that you can find some equally acceptable materials in your own home.

For my catapult’s arm, I decided to use this bendy ruler:


It’s perfect for a catapult not only because it’s purple (which is tied for first place on my list of favorite colors, along with “mustard”), but also because it’s so flexible. A catapult’s arm, you probably know, needs to be bent back. It’s this bending back that traps propulsive force within the catapult, so that when the arm is un-bent, it sends its payload flying. In most catapults, this is achieved by anchoring the bucket-less end of the arm – attaching it to a heavy base or even directly to the ground. But doing so would require a few additional materials. And as I said, for this first catapult, we’re keeping things nice and easy. So my hand, gripping one end of the catapult’s arm, will serve as an anchor.

Now, onto item number two – the bucket. Approximately 90 seconds of the two minutes I spent hunting down materials for this catapult was spent in search of a proper bucket. I finally found it in, of all the places, the recycling bin.

Here it is:


If you’ve identified the object above as a particulary uncomfortable squirrel hat or as a shrunken pink hockey puck, I have bad news: you’re wrong. It is, in fact, the cap of a milk carton. I gave the cap a good rinse, set it aside to dry, and then reached for the final item on my list – something to help attach the bucket to the arm. It took no time at all to find the perfect thing. I didn’t even have to think about it. And if you’re a regular reader of this blog, you’ve probably already guessed what it is I reached for.


That’s right, DUCT TAPE! That most glorious (and gloriously useful) of all adhesives.

Okay. So we’ve got our materials. Now what?

We build, of course.

I’d list the steps for you, but that seems unnecessary, considering there’s only one. Simply take a piece of duct tape . . .


. . . make one of those little inside-out loops . . .


. . . and use it to stick the bucket to the end of the arm:


Et voila! That means “Now let’s go launch some stuff!” in French. And if you look around your house for items like the ones above and build your own catapult, you can be launching in no time. Just grip the bucket-less end of your catapult’s arm, place something launch-able into the bucket, yank back on the arm – and let it fly.

I like to use cotton balls:


If you roll one up in your palm a bit before setting it in your catapult’s bucket, you can get some serious speed and distance out of it.

Action shot! That white blur is the cotton ball, racing toward its target.

Practice makes perfect. But unless you want someone to launch something back at you, you should probably avoid catapulting at anyone. And if you just can’t help yourself, then at least make sure your projectiles are nice and soft.

Happy catapulting!

. . .

For each catapult I make over the next few weeks, I’ll include a final rundown – a quick look at the difficulty and potential costs involved in making it, and also some suggested uses should you choose to build your own. The rundown for this first catapult is as follows:

Name: Cotton Ball Blaster

Difficulty: piece o’ cake

Cost: if you’re smart enough to have a roll of duct tape in the house, zero dollars and zero cents

Uses: annoying siblings; launching lightweight pieces of trash into the trashcan; battling an army of invading snails

Duct Tape!


Here’s another thing the EngiNerds love, and maybe even more than catapults and robots: duct tape. Yes, that ultra sticky, silvery gray stuff that there’s most likely a roll of somewhere in your basement.

Before we get to talking about the actual tape, though, we should probably talk about how to talk about it, seeing as it’s been a controversy that’s been raging for decades . . .

“Duct Tape” vs. “Duck Tape”

There are a number of theories out there about the origins of the terms “duct tape” and “duck tape,” and the proponents of them all (especially the makers of the tape themselves) can get pretty fierce. The only thing that all sides agree on is that the stuff we know today as duct tape or duck tape first appeared and became prevalent during World War II.

World-class word nerd Jan Freeman, writing in The Boston Globe, gathered up a handful of the most popular theories: the one that claims “duck tape” refers to the cotton duck fabric backing of the original adhesive, or the one that claims it refers to the tape’s waterproof properties, moisture wicking off its silvery skin like water off a duck’s back. There’s even a theory that claims the name derives from the amphibious DUKW (called “duck”) boats that were used during WWII and that can now be seen carting tourists all over Boston.

duck tour

No one can agree – and, more importantly, no one can prove for certain – whether it’s “duct tape” or “duck tape.” But at the end of the day, what you call it really doesn’t matter. What matters is that you keep a roll of it handy at all times, because the uses of the stuff are pretty much endless.

What Can’t You Do With Duct Tape?

The list of things you can’t do with duct tape is probably shorter than the list of things you can do with it. Just ask Tim Nyberg and Jim Berg, the so-called “Duct Tape Guys,” who have written half a dozen books (!) on what they affectionately and not all that hyperbolically call “The Ultimate Power Tool.”

tape book

Surely you’re familiar with duct tape’s usual uses – sealing and securing and the like. But that’s just the boring, obvious stuff, the equivalent of Clark Kent’s work as a reporter at the Daily Planet. Hidden in every roll of duct tape is a world of more exciting, unusual, and even superheroic possibilities.

Maybe, for instance, you’ve seen someone whip out a duct tape wallet. Or maybe you’ve seen someone using a smart phone or iPod that’s protected by a duct tape case. But duct tape has also been used to make sandals and neckties and even entire prom dresses and tuxedos. You might find a duct tape hammock in a crafty do-it-yourself-er’s backyard, or duct tape covers on their couch cushions. Open their refrigerator, and you might see some duct tape shelving, and over in the cabinets there might be stacks of duct tape cups and bowls and plates. Legend has it that someone once dove out of an airplane with nothing but a duct tape parachute to ensure they made it to the ground safely, and the MythBusters – a pair of EngiNerds par excellence – once used duct tape to build a bridge, and another time to lift a whole car.


If you need any more convincing as to duct tape’s strength, reliability, and versatility, consider this: NASA, a group of well-prepared brainiacs if there ever was one, has made sure there’s a roll of the stuff on board every mission since way back in the 1960s. Duct tape is even credited with saving the lives of the three astronauts aboard the famous Apollo 13 flight. In an interview back in 2005, Ed Smylie, one of the engineers responsible for coming up with the lifesaving solution to the problems the Apollo 13 astronauts faced, claimed that as soon as he confirmed there was a roll of duct tape on the shuttle, “I felt like we were home free.” He went on to add, “One thing a Southern boy will never say is, ‘I don’t think duct tape will fix it.’” Which, it just so happens, is one thing an EngiNerd will never say, either.

The Future of Duct Tape

There are undoubtedly dozens, probably hundreds, and maybe even millions of uses for duct tape that have yet to be discovered. And as our world continues to change, pretty much only one thing remains the same: there will always be a place for duct tape. Just think about it – a decade ago, there was no such thing as an iPhone, and now duct tape can be used to make a safe and (if you buy a roll of the fancy colored, patterned, or glow-in-the-dark kind) stylish case for one.

So call it “duct tape” or “duck tape” or “sticky silver stuff” or whatever else you want. Just make sure you always keep a roll of it handy, since you never know when it just might save the day.


Screen Shot 2017-08-16 at 6.04.51 AM

There are a lot of robots in EngiNerds. (And I mean a lot.) Mostly they’re just hungry, but they can do more than eat. They can walk and talk and, well, do the sorts of things we humans usually do after we eat . . . But maybe even more incredibly, the robots in EngiNerds show the potential to learn – to pick up new skills over time.

Reading about these bots, you might find yourself wondering whether any of this stuff could happen outside of a book. Just how smart and skilled can a robot really get? Well, the sorts of machines we think of today as “robots” have been appearing in science fiction stories for decades, and pretty much from the get-go people have been wondering these same things.

Robotics is now one of the most thrilling and fastest-growing fields in the rapidly paced worlds of science and engineering. And whether you realize it or not, it’s possible you already have a robot in your life – and maybe even in your home at this very moment!

Maybe you’ve got an “autonomous robotic vacuum cleaner,” like the Roomba, that scoots around your house on the weekend sucking up dirt and dust so that you don’t have to. Or maybe you have your very own CHiP, the “Lovable Robot Dog” who can learn how to follow you around, how to play soccer, and even how not to do its robotic business in the house. Or maybe you’ve got a robotic teacher’s assistant in your classroom at school.

And even if you don’t have a robot in your day-to-day life, you’ve surely come across one at some point. Robots are playing increasingly critical roles in our hospitals, factories, and military, and in places like Japan, robots can be found nearly everywhere else, too – restaurants, hotels, offices, banks, and stores.

But to return to the question that started all of this (and one of the questions that got me writing EngiNerds in the first place): just how smart and skilled can a robot really get? To help answer this question, I’ve created a list of some of the most jaw-droppingly impressive robots around today. Read about them below — and prepare for that jaw of yours to drop.



NASA’s Valkyrie is, without a doubt, the most forward-looking robot on this list – and maybe the most forward-looking robot currently in existence. Valkyrie was designed – and has since then been continually modified – with an incredibly lofty goal in mind: to help humans build a larger, more permanent presence in outer space, and to make that process as safe as possible. Valkyrie could, for instance, assist with the colonization of Mars. Several other, non-humanoid bots have already traveled up to the Red Planet, learning as much about the place as they can. Should a humanoid robot such as Valkyrie make it up there, it could, say, build sound and secure human habitats, eliminating a tremendous amount of risk and making humans’ time on Mars safer and more efficient. It may seem like something out of a science fiction story, but with both NASA and private companies investing more and more money and brainpower in missions to Mars, this future may not actually be too far off.


method 2

If you’re so inclined to fear the future – especially a future in which we’re surrounded by robots – you might just want to skip this section. Because South Korea’s Hankook Mirae Technology has built the bot that most closely resembles something that might’ve come out of a brilliant villain’s secret laboratory. The 13-foot tall Method-2 is a humanoid robot that can be controlled by a human “pilot” seated inside the cockpit-like cavity in its torso. If the pilot raises his or her arm, the robot raises its (300-pound) arm. If the pilot makes a fist, the robot makes a (metal-skinned, beach ball-sized) fist. And if you weren’t worried before, but kind of are now, don’t be. It’s likely that the giant bot will be used for good – such as for cleaning up wreckage and more quickly reaching survivors in the wake of a natural disaster.



You might’ve seen Honda’s Asimo on the news a few years back. In 2014, during a visit to Japan, President Barack Obama famously played soccer with the bot. But that’s not all Asimo can do – not even close. Its balance and agility – it can hop up and down on one foot, run smoothly and fairly fast, and climb stairs – are unmatched. And its movements are so clean and natural that, watching the bot do its thing, you’d be forgiven for wondering if the massive motor company hasn’t just shoved a small, very devoted actor into a robot suit. Asimo can talk, too, and even interact with humans. The bot can respond to calls, obey commands, and even recognize faces and specific postures and gestures. It’s not hard to imagine Asimo in a home or workplace, serving as a sort of robotic butler and handling all kinds of chores. And it doesn’t hurt that Asimo is polite. Approach the bot, and it’ll probably ask you to shake hands.



Like Method-2, Atlas is a humanoid robot. This one, however, was designed here in the United States, and actually right in my backyard, at Boston Dynamics in Waltham, Massachusetts. Also unlike Method-2, Atlas isn’t gargantuan, but built on a more familiar scale. The bot stands just shy of six feet and tips the scales at 330 pounds – which, in case you’re wondering, would be like if you took a guy the size of Shaquille O’Neal and squashed him down about 14 inches. Like a lot of the robots on this list, Atlas remains a work in progress. The engineers at Boston Dynamics are continually tweaking the bot so that it becomes better at fulfilling its intended purpose – to lend a hand during emergencies and perform potentially dangerous search and rescue missions. Every time Boston Dynamics unveils a new version of Atlas, the bot’s got a batch of brand-new skills, and has usually thoroughly mastered all his old ones. The bot can quickly navigate rough, uneven terrain. It can open doors and lift, carry, and accurately place objects. Watching Atlas’s demonstration videos, you can’t help but feel that robots, made right, might one day do a tremendous amount of good in the world.

Click here to watch Atlas in action.

Spot Mini


The Spot Mini is another of Boston Dynamics’s creations, and in my opinion, it’s the coolest. A cross between a big dog and a baby giraffe, this four-legged, long-necked bot can do an astounding number of things. It can fetch you a can of seltzer, say, then stick around until you’re done so it can put your glass in the dishwasher and your empty can in the recycling bin. It can also effortlessly climb stairs, duck and dodge obstacles while navigating a house or other environment, and, should it slip and fall, it can quickly climb back up and continue on with whatever it’d been doing. And last but certainly not least, the Spot Mini can run. It has clocked speeds of up to 28 miles per hour, meaning it might be more appropriate to call the bot a cross between a dog, a giraffe, and a gazelle.

Click here to see just what Spot Mini can do.

. . .

Not impressed? Well, that’s crazy. But if so, rest assured that in the years (and probably even days) to come, these robots will only get smarter and more skilled. You might even end up with an Asimo or a Spot Mini of your own, hanging out in your house waiting to be bossed around. The trick there is just to, you know, keep the things from eating everything in sight and kinda sorta trying to destroy your town . . .



When you read the first book of the EngiNerds series (you are going to read it, right?!), you’ll find that catapults play a major role in the story, and I wouldn’t be too surprised if reading about them gets you itching to build your very own. The EngiNerds build their catapults using nothing but chopsticks and rubber bands, and while I’d love to share their design with you, that information is TOP SECRET. It took forever to get the guys to share it with me, and I’m the one who created them!

Fortunately, there are loads of great catapult designs available for FREE on the Internet. But first – some nifty history about the catapult . . .

Catapults are known as siege engines, and have been around since ancient times. They are primarily used to launch heavy objects great distances, either at or over things, and all without the use of explosives.

Catapults come in every size imaginable. Technically, your basic everyday slingshot is a catapult. It relies on the same sort of physics that larger catapults do. And believe me – catapults can get absolutely GINORMOUS. These weapons, after all, were used to throw projectiles weighing hundreds of pounds (often big rocks, but also sometimes piles of rotten garbage) at targets that were hundreds of yards away (like an enemy’s castle or city walls).

small catapult
Catapult? Technically.

But catapults weren’t only used during battle. Thousands of years ago, the Greeks – who were, arguably, some of the very first EngiNerds – understood that playing around with catapults could be lots of fun. And so they held catapult-shooting competitions, and even had special contests just for the kids. (The EngiNerds would’ve loved that.)

big catapult
Catapult? Definitely.

And now, finally, on to the fun stuff . . .

If you’ve never built a catapult before, you may be daunted by the idea of doing so. But as mentioned above, catapults come in all sizes, and you may be surprised (and pleased!) to learn that you can make dozens of different small-scale siege engines using nothing other than some fairly common household items. Here are just two websites that offer up several such sets of catapult-building instructions:

  1. The Kids Activities Blog is absolutely jam-packed with activity ideas for kids (and adults!) of all ages. Some of the links on their catapult page are now inactive, but there are still a handful of excellent designs on there, all of them simple, easy to follow, and buildable using easy-to-find items like cardboard, toothpicks, pencils, plastic spoons, and rubber bands.
  1. Spaghetti Box Kids – another great site with a wealth of fun ideas – offers up ten more catapult designs that can be made using mostly common household items. A couple of these do-it-yourself siege engines are slightly more involved than those found on the Kids Activities Blog. But the extra effort will produce a sturdier catapult, and sturdier catapults can, of course, launch heavier objects greater distances. (I’m trying to tell you that it might be extra fun . . . )

Spaghetti Box Kids also provides a handy chart to help determine which catapult design might be best for your kid and/or you to tackle, as well as some great ideas for games that can be played once the catapult is up and running (or, I guess, built and launching).

Over the course of the next few weeks, leading up to the publication of EngiNerds, I’ll be constructing some of my own catapults using these and other designs I’ve found. I doubt any of my catapults will be very useful should I need to defend my town against a horde of hungry robots. But still, it ought to be a good time.

. . .

Psst. If you’re still feeling desperate for more siege engine-related fun, check this out. It’s the music video for the one-of-a-kind band Zammuto’s song “Io.” In it, you’ll see band members, along with their families and friends, build – and then put to thrilling use – an enormous trebuchet (another type of siege engine popular throughout history).


“A boisterous balance of potty humor and geek pride in this rollicking adventure…”

With less than two months to go until the first book of the EngiNerds series hits shelves, reviews are starting to roll in. Here’s one from Kirkus Reviews:


A gang of science nerds unwittingly unleashes a squadron of destructive robots and must engineer a way to save the town in Lerner’s debut novel.

When a mysterious box appears outside Kennedy’s house, he enlists the help of best friend and fellow EngiNerd Dan to sift through the metal parts and hardware. Together, they piece together a polite but ravenous robot named Greeeg. The robot eats all the food in the house—refusing only radishes—and Kennedy discovers that Greeeg is both insatiable and unmanageable. The potential for catastrophe is fully realized when Greeeg propulsively “disposes” (that’s robot defecation) tiny, window-shattering, brown-black cubes. Is the robot from Grandpa K., Kennedy’s hero and a former engineer? Is it coincidence that his best friend also hates radishes? Unfortunately, Kennedy isn’t the only one with a robot problem. Eighteen bullet-farting robots storm town, and the EngiNerds must band together and use ingenuity to prevent the robots from consuming and destroying everything in their wake. Sci-fi readers will enjoy the science and tinkering, but dangerous excreta is pure schoolboy horseplay. The story includes clever duct-tape solutions, the construction of catapults from disposable chopsticks, and a good, old-fashioned water fight in this action-packed celebration of nerd culture. The absence of ethnic markers implies that Kennedy is white, but the surnames of the EngiNerds suggest a diverse assemblage.

A boisterous balance of potty humor and geek pride in this rollicking young engineer’s adventure, the first of two. (Science fiction. 8-12)

Visit the Kirkus website for more great kid lit reviews and recommendations, and keep an eye out for more EngiNerds-related information as the pub date approaches!

Sketchbook (06/01/17)

I’m about to embark on a revision of a manuscript, and in an effort to better sink back down into the world of the story, I’ve been looking through the drawings I did while writing the first draft. Here’s a look at some of them. Below you’ll meet a handful of the story’s main characters, and also find a few hints about what they get up to as events unfold.

. . .

Uncle Carl
FullSizeRender copy
A suspicious Mr. Worrest.
An exhausted Mr. Worrest.
Barnaby St. James (not to be confused with Rich Uncle Pennybags, a.k.a. “The Monopoly Man”)
The cockatrice — a supposedly mythical creature…
A few selections from Uncle Carl’s library.
A few selections from Mr. Worrest’s library (the cover story of GOSSIP was, sadly, pulled directly from an actual tabloid).
MENTAL Magazine — the only thing our narrator is interested in reading.
The curious contents of Mr. Worrest’s fanny pack.
The search for Mr. Worrest.