Deadline of this assignment is set to: 2025-02-28 20:00:00
1. Task: Density
The current era could easily be considered a time of revolution in the field of materials. Slowly, with regular frequency, news about new materials appear in the popular scientific press, the properties of which surpass the previously known materials. Thanks to this, enormous progress has been made, for example, in the field of civil engineering, building and construction, electrical engineering, medicine and many other branches of human activity. One of the properties of materials is its density.
Figure: behavior of three objects with different densities.
Task for rabbits: Build a robot that will be able to measure the density of objects whose density is less than the density of the liquid by immersing them in a liquid. Try to estimate the accuracy of your measurement.
Task for the tigers: Build a robot that can measure the density of objects whose density is greater than the density of the liquid (really greater) by immersion in a liquid. Try to estimate the accuracy of your measurement.
Note: It is possible to use objects other than LEGO parts in the task, but the actual measurement, its control and evaluation should be controlled by the hub/control unit of the robotic kit.
Task for simulants: The density of the material will be expressed in the simulated environment by the density of vertical lines in the robot environment. The smaller the distance between the lines on average, the greater the density - be careful, all the lines will be vertical, but they don't have to be the same distance apart. In the simulation there will be no immersion. You can use for example the following background (or another one that you design on your own):
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2. Task: Waste Recycling Plant
One of the most serious problems today is the efficient processing of waste produced by human society. For example, quite a lot of metal waste ends up in municipal waste, which could be recycled and used. Of course, professional systems exist for this purpose - some are based, for example, on on the so-called rotating magnetic drums (https://www.puritanmagnetics.com/product/rotating-drum-magnets/). in this task we will try to separate waste in our model conditions.
Figure: Automatic sorting line for sorting municipal waste, plastic and paper, source: sollau.sk.
Task for rabbits: A waste mixture containing small metal objects and other waste enters a robotic waste processing plant. Small metal scraps can be, for example, paper clips and react to magnets (the magnet can attract them to itself). Build a plant that can "pull" these metal objects out of such waste using a magnet and move them to a separate container, where they will be separated from the rest of the waste, located in another container. What is important is that it is possible to automatically perform this separation repeatedly, without someone manually removing objects or the entire container from the magnets. The supply of unsorted waste and removal of separated waste can now be carried out manually by workers.
The task for tigers: It is the same as for rabbits, but in the mixed waste, in addition to objects that can be attracted by magnets, there are also conductive objects. For example, metal twisted paper clips are magnetic, aluminum chocolate wrappers crumpled into a ball are conductive, and paper crumpled into a ball is leftover waste. In this case, one batch of waste may contain one conductive or non-conductive object and several small magnetic objects. Even in this case, the plant must work automatically repeatedly.
Note: in addition to LEGO parts, you can also use some magnets in the solution - either permanent or electromagnets and some (non-LEGO) electrical circuit - e.g. for switching the electromagnet, or for detecting conductivity - it can also have its own (non-LEGO) power source - but pay attention to safety, always disconnect the source after testing the model and do not use a voltage above 12V. Please ask a leader or another adult to check your model and ideas before implementing them!
Task for simulants: There are two piles of waste in front of the robot, made up of several smaller objects/obstacles placed next to each other with small distances. In one pile (we don't know if they are on the left or right) there is waste made up of larger (we don't know how much larger or how big) objects, in the other pile there is waste from smaller objects. The task of the robot is to find which pile contains smaller objects and stand in front of this pile. You can use the same background image as in the first task, place some obstacles over the lines - smaller on one side, larger on another side.