Tenergy is a company that you know well even if you don’t know them. They make a lot of the replacement batteries for everything, external power supplies, other electronic items. But recently they’ve added a few items to their line of products that reach out in an entirely different direction.
So far Tomo is my favorite out of the box Robot Build, and I highly recommend it. It is also very reasonably priced (see note on that below).
Tomo the robot has the usual sensors that come with such a device, including a line tracker and a distance sensor that resembles a pair of eyes. The yellow color of the framework and the overall configuration give Tomo a sort of Wall-E look, which is cute.
The makeblock robot is an arduino technology robot. It can be controlled with a supplied controller, or operated from any of several different kinds of computing devices (such as your cell phone) using an app. It can be programmed using the Arduino interface (from a Mac, Windows or Linux computer), but the robot comes with built in capabilities so you won’t need to do that to operate it. Note that the app-based controls provide more functionality than the hand held IR control.
But here we are talking about making that robot into a six legged insect with an add on package.
The add on package consists of the leggy parts of the photograph above. With this add on installed, the robot walks instead of rolls on wheels.
I love the Makeblock Robot and this is a great add on, but before you start investing in this system you need to know a couple of things.
Makeblock itself makes well designed and interesting robots and add ons, but they also produce several slightly different versions of everything they do. They all seem to work fine but there are many differences you will want to track. For instance, when buying a robot make sure you get one with bluetooth, because you will enjoy controlling the robot with your phone, where you will have more options than with the supplied IR controller. When choosing a leg upgrade, there are several options, though I think they all have the same basic parts. Each expansion pack allows you to make a six legged robot (the beetle robot) or a mantis robot, or a crazy frog robot. The kits I know of are:
I would go for the cheapest one, which at the moment, is this one. Whatever you do, don’t spend more than about 30 bucks.
The basic idea is this: The main back wheels of the mBot robot serve as cams for a set of levers. To get a six legged robot, the first lever is attached off center to the wheel, and thus acts like a piston as the wheel rotates. This then drives all the other levers in a series of crude step like movements. The other variants use a similar principle.
Tips and hints for building the mBot legged robot extensions:
This is a DIY kit. Therefore, the manufacturers have less than the usual interest in keeping their product exactly the same for every iteration. This probably contributes to the plethora of seemingly similar but maybe slightly different versions. So, the first hint is to look at the pictures and descriptions closely to see if you can figure out exactly what you are getting, and then, don’t expect the instructions to necessarily exactly match the product. They usually do, but beware.
If something doesn’t seem quite right, check the instructions to see if you screwed up. Whether or not you screwed up, remember: DIY project. Fish some additional bits out of your box of extra parts, figure it out.
The biggest limitation of the robots, especially the six-legged version, is the surface on which they are walking. I have two suggestions that may allow them to be able to turn on a carpet and to keep traction on slipper tile. First, maybe add length to the legs so the thing rides up higher. Second, add feet. Feet that provided a bit more traction would help on tile. Perhaps a simple wrap of electric tape will do this. Feet that are flat attached to the bottom of the legs, like little snow shoes, should both increase traction and allow better turning on shag carpets. If you are going to have this robot chase around your cat, you are going to have to handle a variety of surfaces. We are playing around with some of these ideas.
The kit comes with what are called “lock nuts.” But really, they are “hard to screw on nuts.” They are designed to not unwind themselves to fall off this highly energetic device. Two hints will make their use more effective.
<li>use a socket from a socket wrench kit to hold the nuts when you are screwing in the bolt. This will work better then the little wrench the kit supplies, or your fingers.</li>
<li>there may be some places where the instructions don't tell you to use a lock nut, but you will want to anyway. You will discover these when the nuts start falling off as you use the robot.</li>
In the six legged build, shown at the top of the post, notice that the wheels do not have their tires. Take the tires off. In our kit, the instructions did not say to do that.
Instructions for making the Mantis, and Crazy Frog configurations
The six legged adapter kit allows you to make three configurations. The most complex one is the Beetle, which uses six legs. The other two, Crazy Frog and Mantis, are much simpler.
Instructions are provided to make the Beetle. To make the other two, look at the back of the box and, well, DIY!
If the pictures on the back of the box are not clear, the following images may help:
Notice that with the Mantis, I think you keep the tires on the back wheels. With the crazy frog, you take the tire off.
Want to make your own robot? You can do this the easy way, or you can do this the hard way. Or, both, if you like.
The basic home made robot is a robot because it moves around, and the way that is usually achieved is with two independently powered wheels, a third wheel (or something) to balance the thing, an energy source, some logic circuitry, some sensors, and some sort of remote control.
You can learn how all these technologies work, buy the various parts, put them together, program it, and have your own robot.
The Makeblock DIY mBot V1.1 Robot Kit is just under a hundred bucks, and is a fairly high functioning robot. You have to build it after you get it, but that takes something like 10 minutes. My brother Joe kindly sent one to Huxley, and Amanda and Huxley built it together in short order while I waited and watched, ready to jump in if needed. I was not needed. (Amanda is a scientist and Huxley is a gear head, so of course this was easy for them.)
One of the important features of the Makeblock Robot is that some of the key assembly needed to make a robot of this kind is either obviated by design (I’ll ‘splain in a minute) or made very easy with the use of handy dandy cables.
Normally, to make a robot like this, you’d start with a controller board such as the Arduino Uno . These boards have little thingies to which you attach wires, but they are lined up and organized in such a way that you can also attach a “shield” which consists of pre-fab circuitry to do a specific thing. One kind of shield is a motor control shield. Others facilitate infrared communication, or blue-ray communication.
The core of the the Makeblock Robot is Arduino circuitry already married to, and on the same board as, a motor control and an IR communication circuit. To this are added (by you) a couple of sensor boards and a blue-tooth board. The sensor and blue tooth boards are separate because you may want to swap out the sensors or comm devices that come with the robot, later, when you figure out how it all works and want to do more.
The motor control parts of the board attach to the motors with simple cables. All of it screws together to a chassis, which holds the controller, the brain, some of the sensors, and the wheels.
There is also programming built into the device, so it can do stuff right out of the box.
The robot comes with a small remote, which can be used to send motion commands, and some other fun commands, to the robot via an IR system (just like a TV remote). (If you build one, point your other remotes at the robot and see if you can get a rise out of it by trying different buttons!)
A second mode is “object avoidance mode.” This can be initiated with an on board button, or via the remote. The robot has a sensor on the front that sends out an ultrasonic signal, and then receives it, using time to estimate, bat-like, how far the nearest object in front of it is.
As the robot approaches an object, it stops, and changes course.
This sensor system does not detect when the robot is at the top of the stairs. Repeat. This sensor system does not detect when the robot is at the top of the stairs.
A third mode is “line follow mode.” This involves a pair of sensors at the front of the robot, facing downwards. These detect certain color contrasts, and in so doing, can determine if the robot is over a line, and if so, using some fairly simple (built in) programming, the robot follows the line. The kit comes with a big piece of paper with a black figure eight on it.
You can try to make your own lines, but you will find that your human senses are not the same as the robot senses, so what you think is a contrasting line may not be what the robot thinks is a contrasting line. So, experiment.
And, if you don’t find the line following to be good enough as it is, buy a more sensitive sensor, and program the robot to follow lines using programming mode.
Or buy two robots, attach a ballon to each, on the other end, a balloon popper, and have robot wars in your house. Like this:
Or set the robot up to count time (an hour or two) and then drive around the house holding a giant feather for a while. The cat will like that. I’m pretty sure you can also get an IR sensor more sensitive than the one on board, or a motion sensor, so the robot can actually go and find the cat using body heat or motion. And so on and so forth.
The mechanics of connecting together parts are said to interface or interact with Lego Technic.
Since this is an Arduino based device, the programming can be done in the native Arduino Language (called Sketch, a form of C). But MakeBlock provides MBlock, which is a form of Scratch. (I have two reviews of Scratch books here.) This form of scratch lets you use scratch like programming blocks, and the drag and drop elements, etc. but then translates the scratch program in to sketch. You can use this system in a cloud based form on any platform, and the offline editor currently works only in Windows and on a Mac. (It is possible to run it on Linux, according to what I’ve read, but I’ve not tried it yet.)
You don’t have to know programming to build this robot and have fun with it, but a little bit of programming is easy to do, and this is perhaps one of the best ways for a kid to learn some hardware and some software skills.