Recently, I found an interesting website to learn about ROS and Gazebo. This website is provided by Robotic System Lab – ETH Zurich. Even though I’ve made several ROS project, including the one for my internship at ProtoSpace Toulouse – Airbus, the online course has a lot to offer about ROS.
The first lecture is an introduction to ROS, such as masters, nodes, topics, and launch files. The lecture file can be found in this link. At the end of the lecture, an exercise is given which require students to control a simulation in gazebo using keyboard input as well as to make a launch file.
The video above is a simulation of the exercise, controlled by keyboard using teleop_twist_keyboard.
In 2017, I made an obstacle avoidance for quadcopter using an ultrasonic sensor as my undergraduate thesis project. The goal is to do proof of concept of an ellipsoid based guidance proposed in the following paper. The paper take a fixed-wing aircraft as the model. However, since implementing it on a fixed-wing model is an extremely laborious work, the implementation is done on a quadcopter.
To mimic the radar sensing, in this project, I used an rotating ultrasonic. The ultrasonic is rotated by using a servo that is commanded through a microcontroller, Arduino. The sensing result is estimated as an ellipsoid geometry, considering the size and orientation of the obstacle as well as aircraft velocity vector. A contact point is set as a guidance.
Recently I had an interview for an internship position with Volocopter. It is an Urban Air Mobility (UAM) company based in Germany. As far as I know, this company is one of the most advance in UAM competition.
One part of the interview was an online coding. The interviewer asked me to “provide a list of all prime number up to 1000”. I found this question interesting as a there’s only one characteristic of a prime number.