Building a better robot builder...

Jedi Mind Trick
Jedi Mind Trick's picture

Its after Christmas, presents are unwrapped, everyone has seen and enjoyed their holiday loot…and the novelty of some of the new stuff has started to wear off. The truly cool stuff…though…keeps people coming back for more.

What does this have to do with Science Fiction? Easy. I’m going to talk about Lego Mindstorms. The EV3 to be specific. It is one of those things that you just can not put down.

EV3 is the evolution of the Mindstorm system that we used to dream about when we were playing with our Capsela kits, Lego Technics, Erector sets and even the earlier Mindstorm Robotic Invention Kits. If you thought the RCX or NXT models were great, wait till you get a load of EV3. It truly is the sort of thing that would be right at home in classrooms on Battlestar Galactica or teaching robotic fundamentals to farmboys on Tattooine.

It comes in two flavors, The Retail Kit and the Education Kit. While there are equipment differences between the two kits (software, parts, etc.) the real differences are in the focus – the Retail Kit is souped up a bit…from sensors to the sporty look because it is targeting a male dominated commercial market of people that want to have gee whiz robots doing golly gee sorts of things with minimal time to result out of the box. The Education Kit, while not a svelte and sexy, is really the workhorse. It is fully expandable, supports the full software, and is targeted at those that want to study robotics and learn the mechanics vs having a cool toy.

I picked up the Education version for my daughter. It was not really an easy decision to go for EV3 Educuation. First, the damned thing was difficult to get. It just released in October and you have to SPECIAL ORDER it from distributors vs just swinging through a Toys R Us where the retail kit sits in all its “Hey Daddy, look at this!’ glory. Second, the kit that my daughter has been using in Robotics Clubs/Challenges/Camps/STEM programs is the NXT. Third, there are real differences between the kits and back when I was looking into it, the real puts and takes were a bit obfuscated (More on the real differences below in Geek Stuff).

Ultimately, I settled on the EV3 because the programming GUI is much more intuitive and easy to manage than the NXT. (I figured my daughter could fire up her Macbook, switch on the Mindstorms IDE and start learning the fundamentals that she will apply to building her legion of robotic zombie minions when she makes her run and taking control of the worl…oh. Um. Yeah.)

The Intelligent Brick

As with all Mindstorm kits, from the early RCX to the more recent NXT, the brain of the thing is the Intelligent Brick. The EV3 iteration features a good array of connection features. It has eight connection cable ports (modified RJ12 ports so you retain a good bit of backward compatibility with existing NXT kits), a mini-USB port for direct computer connection, a microSD card slot for expanding the memory, and a full-size USB port for an optional Wi-Fi dongle or daisy-chaining up to three additional Mindstorms Intelligent Bricks (enterprising members of the population would use this feature to increase the connection ports – to go off the script and chain bricks to build bigger, more complicated robots than the single brick would support) The EV3 Intelligent Brick also has built-in Bluetooth 2.1 for directly controlling creations via mobile device. It also has embedded compatibility with iOS for Applites and Android for the Droidheads among us.

Geek Stuff (You have been warned)

The core of the EV3 Intelligent Brick is a 300MHz ARM9-based processor with 64MB of RAM and an embedded 16MB of flash memory. (This memory is expandable exponentially via the aforementioned microSD card slot). This configuration is a leap above the ARM7-based NXT 2.0 (For comparison, it sported 256KB of memory and no microSD card slot). The processor is Linux based (so open source for development), and out of the box, it supports all the functions mentioned above. It should be noted, however, that despite efforts to ensure backward compatibility with previous kits, the rechargeable battery from the NXT can not be used with EV3 (advances in battery technology, I assume).

Like the processor, the sensors also got a power boost and are now capable of relaying to values to the EV3 Intelligent Brick 1,000 times per second, a 3x improvement over the NXT 2.0 sensors. (The Education kit has an optional software program for data logging and the like for experiments. A must, I felt, for really understanding what you can do with a robot and how the robot interacts with its environment). There is also a color sensor that has a Reflected Light mode that removes background light and detects seven colors instead of six.

The EV3 programming interface is upgraded as well. Although the software is different than the NXT programming software, existing NXT users will recognize many of the features of the new programming environment. Programming in the environment is still drag and drop programming blocks, but it has been simplified and cleaned up a good bit. (Never fear, it is still based on LabView platform!) It is also possible to use the EV3 software to program NXT bricks. If you have both NXT and EV3 bricks, this allows you to program both using just one application. It should be noted that this does not impart additional features on to the NXT brick. (i.e. you cannot use EV3 sensors on the NXT brick.) This really just helps keep all your programs in one environment. The EV3 software (home edition) is a free download from the LEGO MINDSTORMS websites. You can use it even if you do not have an EV3 set. A limited functionality version of the software comes with the Retail kit (it supports the five robots that are buildable with Retail Kit elements) and the fully functional, uber cool, build your own robots, log data, and be the master of your own fate EV3 software, however, is a purchasable item for the EDUCATION kit.

The 3D builder app deserves a mention as well. This thing is like a Lego instruction on steroids. You can ‘play’ it to watch a 3D animation of how parts are to be assembled and/or you can rotate the parts in 3D space to view from various angles. There are zoom/pan options as well so you can make sure you have the angle you desire. Being a long time Lego constructor and very accustomed to the 2D instructions, this app was a bit disorienting at first. After a while, though, it became a natural tool and I now even enjoy the idea of rotating and zooming in to on small pieces assemblies to see exactly how they are intended to connect. (This reduces the number of times you realize later that you’ve misseated a block and have to pull things apart to correct.). Once accustomed to how it worked, it has become an amazing, interactive addition to the building experience.

On Brick Programming and On Brick Data Logging is also added as a new function for the Education version of EV3 Intelligent Brick. With these functions, you can take programs or data from the EV3 Intelligent Brick into your PC and, of course, you don’t need worry about the memory capacity because if you need extra storage you can save your data to a micro SD card.

There is also an Auto-ID function embedded in the EV3 Intelligent Brick that allows it to automatically detect what is connected to which port when sensors or motors are connected to the brick. This is a neat troubleshooting measure that allows you to quickly find mistakes in connecting sensors and motors. (Side note, it also tells you when connections are seated properly, albeit indirectly. At some point in the process, handling had unseated one of the cables to a servo. The result was that you could download the program to the brick from the PC and it would start…and then abort. This was puzzling until I thought about the auto detect and checked reseated all the connections in the ports. After doing this, the program ran perfectly from tethered-to-laptop test and untethered execution straight from the Intelligent Brick. This really is a cool feature since it aborts execution when all elements are not effectively ‘ready’. This will save unnecessary or improper wear on parts or unintentional damage from having one portion of the bot operating when another isn't.

As you can imagine, these upgrades mean your robots can be much more complex than with Mindstorms NXT 2.0.

There are a few key differences between the Retail and Educational kits. My quick compare is as follows:

EV3 Education Building Elements vs EV3 Retail Building Elements –

There are a number of elements that are different between the two kits. These differences are driven mainly by the Retail Kit’s focus on building its five robots. It probably wouldn't do to list every element bar and element connector that is different between the two kits, but in aggregate, the differences net out to the Retail Kit being equipped with comes 541 components/elements and the Educational Kit weighing in with with 550+ components/elements.

The real differences come in how the two kits ship with software and hardware. Differences I can tell are:

Software in the EV3 Education Kit vs EV3 Retail Kit -

EV3 Education Kit EV3 Retail Kit
Programming: EV3-G EV3-G
Data Logging Software: YES NO
Content Editor: YES NO

Note: It is worth mentioning again that the data logging and content editing software do not come with the stock Education Kit. They must be purchased separately. These things are, however, available as an extension of the Education Kit. Conversely, all you can get/use (exclusive of some hackerly work on free downloads and Intelligent Bricks) with the Retail Kit is the retail software that covers the five or so models in the Retail Kit

Hardware in the EV3 Education Kit vs EV3 Retail Kit –

EV3 Education Kit EV3 Retail Kit
Rechargeable Battery: YES NO
Intelligent Brick: 1 1
IR Beacon (Infrared Remote): 0 1
Infrared Sensor: 0 1
Ultrasonic Sensor: 1 0
Touch Sensor: 2 1
Color Sensor: 1 1
Gyro Sensor: 1 0
Large Motor: 2 2
Middle Motor: 1 1

After you've assembled a few robots and are accustomed to looking at their programming files, you can program from scratch. The Mindstorms EV3 programming language is a modified version of National Instruments' LabVIEW software used for programming measurement and control systems and every servo motor, sensor, and logic operation is represented by a colored icon. The entire operating process is presented as, what amounts to one large, complex if-then chart. It’s surprisingly intuitive and extremely powerful. The tie to LabVIEW is a good one, since this is the software that would likely be used as basis of real world jobs with elements of programming of robots and robotic devices.

Servos/Motors

EV3 Servo Motors are comparable to NXT motors in terms of speed and torque, although their shape is slightly different to make building easier. The kits come with Large and Medium motors, in different variations. The Medium Motor is comparable to the Power Functions Medium version of the same. As is the case for NXT, all three motors have rotation sensors for position and speed control.

Sensors

NXT kit owners will recognize some of the new sensors. The EV3 Touch sensor, EV3 Color Sensor, EV3 Ultrasonic Sensor (Education set only), closely resemble their NXT counterparts. New sensors for the EV3 system include a gyroscope (Education set only) and an Infrared Proximity Sensor with Remote Control (Home edition only). [Note: I DID SAY GYROSCOPE! You can actually build a robot that balances on two wheels called Gyro Boy. Not sure, but I think my excitement at this is a Geek Cred item all by itself.]

Difficulty

The only limits to what you can do with the EV3 is your imagination and the set of sensors, servos and building elements that you have available (The Education Kit is immediately expandable with a separate kit that adds additional elements and the IR/Remote Control sensors from the Retail Kit can be purchased if you want/need them). It is worth noting that it took my nine year old daughter about 20 seconds to get aligned to the programming environment and begin programming. Her first program was to have a basic education robot (called a rover) navigate in a perfect square. She programmed this by figuring out the number of wheel rotations needed for the desired distance and then programming the turns (which teaches angles, BTW since the turns are declared in degrees of shift from forward angle). Immediately after the square she programmed a figure eight navigation (she chose to solve it as two nearly identical, reflected mirror image squares vs circles or triangles). So, far from becoming overwhelmed with the elements, the program, etc, she just hopped in and started being a Maker.

Conclusion

All in all, the upgrades to processor, sensors and overall kit create a sense of unlimited possibility as you look at the potential of the kit. You’d have to be fairly advanced in robotics to surpass the capability of the set. I’d expect that an investment in EV3 will support a younger child’s robotic development ambitions at all levels of education…elementary, middle, high school and college. The EV3 will replace the existing NXT kits that are currently the staple of school robotics curricula, so until there is a new evolution of the Mindstorms that replace the entire EV3 platform, the set will be useful. (Of course there will be additional sensors and the usual suspects pneumatics, magnetics, gear sets, etc that will be added – but these are supplements and should be natural extensions to the kit.) For adults that just like Legos and robots, the applications are endless as our interests. For me, I have my old RCX and NXT sets that I use to make prototypes for my Halloween animatronics…and I’m pretty sure, at some point, the sets will all get mingled. LOL.

In summary, this new EV3 set is just insanely cool. You can program snakes that strike when IR beam is crossed with Retail Kit or program a gyroscopically balanced wheeled droid with the Education Kit. Of course, there are lots of designs/ideas up and down the range around these in both kits that will help teach real application of math principles like area, circumference, distance measures and, of course, addition, subtraction, multiplication and division. It is also a problem solving workshop with infinite use and configuration.

Truly, this is a product where you will get out of it whatever energy and effort you put into it – whether it is just having fun building standard kits, solving for new designs or using it as a way to share and bond with your children over a passion or interest. I’d think that a set like this could produce lots of memories, learning opportunities and serve as a solid foundation for late.

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