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New MOSS Robots Satisfying to Build, but Too Easy to Crush

Rafe Needleman
Editorial Director, Yahoo Tech
July 9, 2014

Since I am the father of an 8-year-old nerd, and since I am a nerd myself, for the past three years I have been buying toy robot kits. For the kid, of course. Each birthday the kits are a little more advanced — more programmable, more intricate. But a few days ago I received a new robot construction system from Modular Robotics that I don’t think I’d consider for my son.

MOSS scooper robot
MOSS scooper robot

A magnetic MOSS scooper robot, from the big ($480) kit. Its Bluetooth module makes it steerable from a smartphone. (Photos by Rafe Needleman/Yahoo Tech)

There are three reasons for this: First, these kits make fragile robots, and when they fall apart, pieces roll under the furniture. Second, they are very expensive. And, third, I think I’d have more fun with them than he would.

The kits are called MOSS robots. The core pieces are small cubes that have powerful magnets in their corners. Small steel spheres fit into indents in the corners and serve as mechanical connectors between blocks, as well as providing the electrical ground for the power and data signals that are sent between the faces of connected blocks.

The blocks are functional: There’s a battery block in each kit, and depending on the kit you get there are also various moving pieces (motors and pivots), a variety of sensors (light, sound, distance), a Bluetooth module (for smartphone-controlled robots), and various mechanical bits like wheels, braces, and inert connector blocks.

MOSS robot under construction
MOSS robot under construction

The scooper robot under construction. The metal balls are held on with magnets embedded in the blocks.

Working with MOSS is tactilely pleasing. The pieces snap together nicely. Following the instructions with each kit reminds one, somewhat, of a good Lego Technic kit, in which you can see the designer’s mechanical creativity revealed a bit at a time as you put the kit together, and then at the end you marvel at the way it all fits so elegantly.

Almost all MOSS pieces have a dual purpose: They’re both structure and software, or at the very least you’re using them to carry signals from one place (like the Bluetooth module) to another. That means you have to think on two levels when designing your robots: how the construction will hold together, and how the data and power will flow through the blocks.

While this is a rewarding intellectual exercise, I was not sure it was illustrative of real-world robot building. When engineering a mechanical system, at least at the start of a design, the structure, power, action, sensing, and data needs each present different challenges and call for different solutions and materials. In a MOSS robot, everything is cubes. The solutions you come up with to make a MOSS robot would not appear to translate well to typical building materials, even if the discipline of multilevel thinking might.

I asked Modular Robotics CEO Eric Schweikardt about this, and he gave me a fascinating answer: “For the last 100 years,” he said, “we’ve been building things along this Cartesian mind-body divide. We have to think more about shape and behavior. I am convinced that mind and body are closely coupled. To become smarter about artificial intelligence, we need to think about mind and body together.”

But nature isn’t made up of cubes, I said. “We’re playing with amorphous robots and soft shapes,” he replied.

And now I’m looking at the philosophy behind these cube robots in a whole new way. And I’m definitely looking forward to future releases of MOSS kits.

Partly disassmbled MOSS robot
Partly disassmbled MOSS robot

First the scooper mechanism fell off when the pivot motor over-extended, and then the rear wheel assembly collapsed when I tried to pick up the robot.

No amount of philosophizing will change the fact that the current MOSS robots are delicate, however. The magnets that seem so strong when you’re snapping your first two cubes together aren’t as impressive when your robot grows to several blocks long and starts to get heavy. If you’re building a robot with lifting capability, it’s difficult to get it to move its own weight without fracturing, to say nothing of picking up other objects. If your robot is on wheels, and you drive into a wall or lift it wrong, it will come apart and possibly magnetically reform into a new mutant construction, meanwhile ejecting steel connector balls into your heater vents. If you’re used to how Lego models break when you drop one, this isn’t that. Lego pieces just snap off, they don’t reattach themselves or run away from you.

Schweikardt is aware of this issue and hopes to eventually use hollow spheres as connectors instead of ball bearings. Up to 75 percent of the weight of a robot right now can be the little round connectors, and that’s the big problem. Unfortunately, the cost of hollow spheres is prohibitive compared with ball bearings.

And price is already an issue. I tried two MOSS kits. The $150 starter kit, called the Zombonitron 1600, has 16 blocks, including two motors and two sensors. It is a truly excellent executive desktop toy. I also tried the mega kit, the Exofabulatronixx 5200, which is a staggering $480. It has two motors, two powered pivots, five sensor blocks, two flashlight blocks, and a Bluetooth brain with eight connections (for sensor input or motor control output). The Bluetooth module can be controlled with a smartphone app, so you can make remote-controlled MOSS bots, or it can be programmed with a computer.

Available for sale for the first time this week, the MOSS kits are flawed, but they make for fun and interesting robots. Their building concepts will stretch your mechanical and software creativity. Just be sure to do your building in a kiddie pool or something, so when you drop those little ball bearings they don’t get away from you.

Rafe Needleman can be reached at rafeneedleman@yahoo.com. You can follow him on Twitter at @rafe.