Robot with big cardboard wheels
If you want to make a robot with big wheels from the LEGO Mindstorms EV3 (45544) educational set, but you don’t have such wheels, don’t be discouraged. You can make them yourself from thick corrugated cardboard. How to make a robot with large cardboard wheels so that the wheels spin normally and do not fall off, I suggest you read in this article.
The robot, after you collect it, will move like this:
As you can see, he will be able to make quite sharp movements, and if you get used to it, you can do these somersaults:
So, where to start making such a robot? Let’s make the wheels first. You need to find corrugated cardboard with a thickness of 6-7 mm. You can glue several sheets of cardboard to achieve the required thickness. I made wheels with a radius of 123mm (diameter 246mm). So, take a piece of cardboard and use a compass to draw two circles for each wheel. Then cut out the future wheels with a paper knife.
Now stick the LEGO axle in the place where the compass needle was stuck to mark the center of the circle.
Now make a template for making holes from LEGO parts, as shown in the diagram below (a large gear with 4 rails fixed to it with 7 and 9 holes).
Put the template on top of the axis (which we have stuck in the center of the cardboard circle) and circle the outline with a pencil. Please note that the slats must be set at an angle of approximately 45 degrees with respect to the waves of the corrugated board. So the cardboard will better support the weight of the robot.
Here is what you should get:
Now, with a paper cutter, cut holes along the marked lines.
Check if the template fits snugly into the hole. He shouldn’t talk.
Make the second cardboard wheel in the same way. By the way, after the wheels are ready, you can paint them with paints by drawing fancy patterns, lines, dots, etc. etc. Send links to your photos with ready-made robots below in the comments.
Now, so that the cardboard does not sag or tear at the edges, we will protect it with a food-grade PVC hose with a diameter of 8×11 mm, see the photo below. Such a hose can be found in hardware or construction stores.
Here is a larger photo of the hose:
Cut a piece of hose about a little longer than the circumference of the wheel and cut it lengthwise with scissors. So insert the scissors inside the hose and start cutting it:
The hose is twisted, and it is better to cut it on the inside.
After that, put the hose on the wheel, you get a kind of tire fitting :).
And so on until you put on the entire hose.
After that, the excess can be cut off. Here’s what the joint looks like:
Now glue the joint with transparent tape.
Cut off excess tape. This is what the finished joint will look like:
Do the same for the second wheel.
Now that the wheels are ready, you can assemble the robot according to the scheme:
For the finished robot, you can write your own program. You can attach any sensors to it. We limited ourselves to simple control from a smartphone using the RoboCam application.
You can download the settings for the RoboCam application from the link below:
How to import settings into the RoboCam application and how to configure it yourself, read in my series of articles.
Questions, suggestions, comments, and, most importantly, photos of what you have done, you can leave in the comments to this article below.