I get asked all the time, “which is the better system?”, so I thought I would put together my thoughts.
I am very lucky to have had both LEGO and VEX send me complimentary kits. I have also been a guest of LEGO at the 2010 LEGO World Expo in Zwolle and a guest of VEX at the 2014 VEX World Championships in California. Both companies have been very generous to me for which I’m extremely grateful!
This is not a review about which is best as a birthday present or which would be most competitive at a robot competition. This review is aimed squarely at the use of robotics in an educational setting to teach STEM concepts. This is a review based around the use of these systems in a Classroom. My focus has always been an educational one, and while both sets do have a strong retail presence, I prefer to look at them through the eyes of a Teacher. In this review, I’ll also be taking the view of a fairly novice teacher, new to the area of Robotics in Education. While there is an already huge community of experienced teachers in this field, these people typically have the resources and knowledge required to use whatever resources they have available to them.
Both kits come with a controller, motors, sensors and building pieces. They both employ the same building philosophy of being a modular, toolless construction system. You use pins and specialty connectors to assemble together various beams and plates to make your robot designs.
The EV3 system ‘feels’ a bit stiffer and things generally tend to click together firmly without too much thought. The VEX IQ plastic beams are a little thinner than the EV3 ones, and as such have a bit more flex to them. This requires a little more bracing to make sturdy robots, but it also allows you to bend the longer beams without damage, allowing for some ‘interesting’ shapes that wouldn’t otherwise be possible. The VEX IQ system however has a greater assortment of larger plates and beams which makes building larger contraptions a lot easier. The EV3 has more ‘pretty’ pieces, that functionally don’t do a huge amount, but do allow nicer looking robots. VEX have recently created a large array of coloured beams and connectors and the VEX Hexbug line has some cool looking ‘pretty’ parts that are compatible if you want to go down that path.
The EV3 is compatible with every other LEGO kit and the VEX IQ is compatible with all the other VEX EDR Metal products. Both kits have a great assortment of parts and come in a sturdy plastic box with a divider tray to keep things organised.
Winner: It’s a Tie.
In a classroom environment I’m most interested in a quick build of a simple robot base so that I can get stuck into programming. Even after we explore simple programming, I’m looking for a system that can then expand to simple mechanical extensions eg. grippers, levers etc.
Both systems provide enough basic parts to build a simple robot and some additional attachments for a STEM based classroom course. While the additional LEGO connector types would allow more complex and intricate building, in my classes (which sometimes number 30+ kids), I prefer to do the simple things really well, rather than try anything fancy.
The standard LEGO EV3 Core set (45544) comes with the following
EV3 Brick (the brain), 2 Large Motors, 1 Medium motor, Gyroscope Sensor, Ultrasonic Sensor, 2 Touch Sensors and a Colour Sensor
The EV3 brain allows 4 inputs (sensors) and 4 outputs (motors) and you can use the on-brick buttons as additional sensors. The EV3 Core set comes with a rechargeable battery that can be charged while it is stil in the controller (providing you don’t build over the charging port. The EV3 can also be run with 6xAA batteries should you need to.
The VEX IQ Starter Kit comes with the following;
VEX IQ Robot Brain, 4 Smart Motors, 2 Touch LED Sensors, 2 Bumper Switches, Distance Sensor, Gyro Sensor, Colour Sensor.
The VEX IQ Brain can take up to 12 inputs / outputs which you configure in the software. This means that it doesn’t matter what type of thing you plug in (sensor or motor) as long as you don’t do more than 12. The VEX IQ is powered by a rechargeable battery only. Unfortunately this means that if someone forgets to put it on charge, you’re out of luck for the lesson.
Both kits have Touch/Bumper sensors, Ultrasonic/Distance Sensors and a Colour Sensor. Both also come with a rechargeable battery which is crucial in a classroom environment. The EV3 has 2 larger power motors and a medium motor which allows for some flexibility, whereas the VEX IQ has 4 of their Smart Motors. All motors have enough torque to perform the tasks you’d expect from classroom activities. All sensors work as you’d expect in a classroom, and while there may be some subtle discrepancies in range / accuracy, you won’t see it when doing your typical education based activities.
Winner: VEX IQ.
The 12 input/outputs are a big plus for me and a total of 4 motors in the standard kit allows for things like grab-and-lift mechanical attachments to be added with ease. While I know it’s possible to do that with just a single motor, that’s not a challenge I’d give to novice students. The Touch LED sensors are pretty cool as well and the ability to switch it’s output colour is a useful tool for students to help debug. Special mention to the EV3 Display which allows things like images, but the lack of a backlight and small text makes it difficult to read (especially amongst some ‘older’ teachers without the visual sharpness of vision their younger colleagues have).
Both systems can be programmed with RobotC, an excellent text based programming language from Robomatter that is also exploring graphical interfaces. However, they both have their own Graphical Programming Interface that they recommend.
EV3-G. This graphical software is extremely easy to use and is very intuitive. Robot commands are easy to find and the on-block configuration makes it easy to modify and experiment with. Constructing simple programs is a breeze and as a teacher it is easy to read the programs to help kids debug and problem solve. The education version of the software has a powerful Datalogging component that allows the EV3 kit to branch well beyond robotics and into some fantastic Science and Math opportunities. EV3-G has a full-featured content editor which allows students to document their projects as they go. The LEGO software has also be translated / localised into 15 different languages, making it a truly global product.
Modkit for VEX. This graphical language is built on the SCRATCH framework and uses a similar idea of dragging and snapping together blocks. MODKIT runs in the browser which means there is no need to install software. There is an offline version of the software in the works for those schools with bandwidth / firewall issues. The software is split into two sections;
Robot Setup: This is where you define which Ports the various motors and sensors are plugged into as well as the dimensions of your robot, wheelbase length, wheel sizes etc.
Programming: This is where the instructions are assembled. Each electronic component of the kit has it’s own processor, which means that you can have say a motor running it’s own set of instructions at the same time as a sensor or the main brain itself. If your students have used Scratch before, they pick this language up immediately.
Winner: LEGO EV3.
The EV3-G software is very easy to use and very intuitive. I spend very little time showing the students what to do as they figure it out very quickly. The Content Editor is extremely useful for students as they can document their projects as they go. While this could be done in another program, having it right in front of the students eyes is very valuable. Modkit is certainly making improvements with their software and their latest release improves on the block click-and-drag experience from previous versions. Modkit requires a little more reading than EV3-G, and as such younger kids without as well developed literacy skills struggle to put together programs. While the parallel processing of the VEX IQ system can be extremely powerful, in a classroom situation, it would not be used to its full potential.
The LEGO MINDSTORMS system is a very mature system with plenty of 3rd parties making sensors that can plug directly into the EV3 brain. HiTechnic and Mindsensors have a dizzying array of sensors you can plug straight in. The VEX IQ Controller is a nice addition to the IQ kit, as it allows you to remotely control your robot. Handy if you’re looking at a more mechanically based challenge and don’t want to fiddle around with the programming too much. I can’t find any 3rd party sensors for the VEX IQ, however, that doesn’t mean they don’t exist!
Winner: LEGO EV3.
The range of add-ons is pretty impressive, but I will caveat this with a few points. The MINDSTORMS system has been around for quite a while, allowing 3rd party suppliers time to develop these sensors. I’m under the impression that VEX are keen for the same thing to happen, and will be encouraging and supporting anyone who wants to make compatible sensors. The sensors that come in a standard kit for both the EV3 and IQ however are more than enough for a classroom application, and as I’ve mentioned previously, in a novice classroom,I prefer to do the simple things well and thoroughly, rather than trying anything fancy.
(disclaimer, I have a very popular teacher resource book for the EV3 and will shortly have one for the IQ)
There is a huge range of educationally specific material that is available for the EV3. The EV3 Design Engineering Projects (US$299) is an official product from LEGO with a full curriculum laid out in an easy to access manner. LEGO also have an EV3 Space Challenge (US$329) and EV3 Science pack (US$199) which are filled with excellent and relevant activities. All these resources are translated into 12 different languages.
Robomatter also has an extremely good curriculum guide and there are a number of excellent free online courses you can take as well.
There are quite a few books based around EV3, and while the majority are focussed on the Retail version of the kit, there are a few good ones for the Educational version.
The official VEX education offerings are a little on the lean side. They have a nice Curriculum set out, but it is fairly broad and instead highlights a lot of the overarching principles of STEM. This is all provided free on their website. It would have been nice to have seen exactly how to solve at least some of the activities from a specific Modkit or RobotC point of view, especially for novice teachers who need some hand-holding to get started. Robomatter have an equivalent VEX IQ curriculum set which looks really nice.
Winner: LEGO EV3.
There are currently far more resources out there for the EV3 than the VEX IQ. They are extremely high quality and very comprehensive. Many of the LEGO offerings are complete classroom solutions meaning teachers just need to follow the instructions for a very thorough, educational rigorous, unit of work. While you don’t have to purchase additional materials in order to use either of these kits in class, I know that a novice teacher certainly appreciates a little guidance when starting out.
Prices are taken from the US sites of each company. Prices may vary in your region!
EV3 Core Set: $339.95
EV3-G Software Site Licence: $399.95 (N.B. The retail version which does not have tutorials / datalogging is free, although it use in classrooms on multiple machines is questionable)
VEX IQ Starter Kit: $249.99
Modkit for VEX: Free
Winner: VEX IQ.
The Starter Kit has more motors and sensors and is about 30% cheaper than the EV3. In addition, you don’t need to purchase any software to get started. LEGO offer a 12 robot deal, (good for a class of between 24 and 36 kids) and so I’ve made a comparison with an equivalent number of VEX IQ sets. VEX have a deal with 12 of their Super Kits (Starter Kit + Controller) but do not have an equivalent deal with the Starter Kit on their website
Prices are again taken from the US websites:
VEX IQ: 12 x Starter Kits = $2999.88
LEGO EV3: 12 x Core Sets + Site Licence = $4366.95
I know you’re going to hate me for this, but I can’t pick a standout winner.
The EV3 software is fantastic to use, especially at younger age groups and the robots certainly can be made to look really nice. This is not to be underestimated when engagement of a class of students is at stake. The supporting curriculum material is excellent and there are plenty of classroom ideas and activities readily available.
The VEX IQ’s cheaper price as well as its ability to take 12 inputs / outputs is very appealing, especially for the budget conscious school. Cheaper robots mean I can work with more students. The Modkit team are really receptive with feedback about their software, and given it is browser based, they are rapidly improving the stability and features of the software.
I’d love to hear your thoughts!