Robotics Unit 2: September 13 Reflection

Today we were introduced to Carnegie Mellon Robotic Academy, a website that gives tutorial on how to use and program robots, such as the Vex Squarebots we are using in class. We were given the task to watch the videos on the shaft encoders and learn how to use them. From the videos I learned that they measure rotations in degrees akin to the traditional 360 degree measurements. However, an important factor to remember is that intertia and momentum area factor, and thus if we program to have the robot stop after the wheels move 720 degrees, it ends up around 780 degrees due to the momentum and inertia the robot have when moving forward. Andrew and I taped the wheels on the robot to observe this occur, and use the sensor debugger to find the exact degrees the wheels rotate.

WhatsApp Image 2016-09-13 at 3.08.33 PM

Then, as we had extra time in class, Andrew and I began to program a function that turns a robot depending on how many degrees we want it to turn. We do this by setting the variable we enter in the function as the degrees we would like it to turn, and then multiply it by a constant, which we had to do multiple trials for, to determine the number of degrees one of the wheels should turn for the robot to turn the correct degree. Then we would have the motors rotate, one forward one backward, until one of the encoders reaches the designated degrees. We only managed to make it to turn right currently. However, we could use “if” and “else” statements next class to make the robot turn left or right depending if we set the degree as negative or positive.

WhatsApp Image 2016-09-13 at 3.07.25 PM