Logo Interreg Slovakia-Austria European Regional Development Fund Faculty of Electrical Engineering and Information Technology, Slovak University of Technology Logo Robotika.SK Logo Faculty of Mathematics, Physics and Informatics, Comenius University    Centrum vedecko-technických informácií SR

Deadline of this assignment is set to: 2016-05-20 20:00:00

1. Task: Get the ball and uphill racing contest

1. We have measured various manifestations of weather last time. A common parameter to estimate the weather is the atmospheric pressure. We are curious to see if you could measure that too.

Air pressure is an interesting variable in general. For instance, take a wooden block and make a cylindrical hole where you can fit a light wooden cylinder as shown in the picture. When we are told to remove the cylinder from the block, we can do it in different ways: a) the block can be turned around and the cylinder will drop out; without turning: b) we can move the block in a fast movement upwards and stop - the cylinder will continue the movement and jump out due to its inertia, and without moving the block at all: c) place the block on the table, and blow some air above it - the cylinder will jump out due to underpressure!



If you have some time, try it on your own! (we learned about this experiment from Mr. Beňuška, a teacher from Center for popularization of Physics at secondary grammar school in Martin - worth your visit, if you are passing by). In the following task, we will also be removing a small object, but we do not need to use air pressure this time...
Task: Robot is located in an open area. A paper cup is placed at some unknown location in front of the robot. The cup contains a usual plastic LEGO ball inside. The task for the robot is to find the cup, remove the ball, return the cup to its original location, and return with the ball back to its start. It is not needed to unload the ball, only to come back with it.

2. Build a robot that can drive forward on a steep tilted surface (some simple car-like robot). Make sure you can change the steepness of the ramp. Place it at the beginning of this ramp and start with moderate angle. Try to find how fast it can go - which of the possible speeds 0-100 (the value POWER in the move block) it can handle while driving upwards. Measure the time needed to travel up for different POWER settings between 0 and 100. Compute the real velocity and draw a chart showing the dependence of the real speed on the POWER setting of the move block. Change the inclination of the tilted plane and repeat the measurements. Do you get a different graph? If yes, what has changed? Try several different inclinations. If you have a spirit of an experimenter, try all of this again, but place some heavy object on the car. How about the graphs this time? Could you build a car for which the difference in the graphs for different speeds will be less? After you have read this task specification, try to answer the questions in advance, before you try the experiments. Finally, compare your answers with your expectations.

Solutions