Simulating Multiple Vehicles in PX4 SITL Gazebo

Jaeyoung Lim Previously, it was only possible to simulate multiple vehicles in SITL by extending ROS launchfiles. However, this is not scalable especially when you are trying simulate large number of vehicles or change the number of vehicles a lot. Now you can simulate multiple vehicles in PX4 SITL gazebo, without depending on ROS. Simply…

Offboard gimbal control using MAVROS for object tracking

Jaeyoung Lim Controlling a gimbal for object tracking is one of the essential functionalities for flying camera applications. A mount plugin was implemented in mavros to enable continuous control of gimbals from the companion computer. The following video shows the gimbal controlled in order to look at a single ROI while following around a trajectory…

Aggressive trajectory tracking controller for MAVROS using geometric control in SE(3)

Jaeyoung Lim As PX4 doesn’t support aggressive trajectory tracking capabilities just yet, a trajectory tracking controller is needed to run aggressive flights. MAVROS enables you to control a drone offboard, supporting low level commands such as actuator control / bodyrate control. This gives you the safety of having a fail-safe flight controller and the flexibility…

Using mavlink-router to route MAVLink streams over the network

Jaeyoung Lim MAVLink is a standard protocol which is used for drones both for internal communications and external communications. It is a popular interface for flight controllers such as PX4, Ardupilot, Betaflight and more. This was mainly used for GCS such as Qgroundcontrol, Mission Planner for the command control link. However, this is also useful…

Exercises of Programming for Robotics – ROS

Programming for Robotics – ROS is an open lecture by Prof. Marco Hutter of ETH Zürich Robotic System Laboratory. The course materials and online video lectures are avilable on the website. The source code for exercises from Dongho is on the Github. The repository was made public with Prof. Hutter’s permission. Please use it for…

Virtual Reality Flight Simulator: ICARUS

Jaeryoung Choi, Soomin Lee, Dongho Kang, Jaeyoung Lim This project was done during Virtual Reality 1 course held in spring 2017 ETH Zurich Overview Project ICARUS is a virtual reality flight simulator which the user stays in the air by pedaling the bike. For more information, you can visit the ICARUS Project Github Demo day…

ROSPPM: ROS Package for Accessing RC Transmitters

Jaeyoung Lim Introduction RC Transmitters are used to control miniature cars and planes for a long time. Although the technology has evolved quite a long way, RC transmitters are still the most reliable way to gain control of a UAV for long distances. RC Transmitters are very simple to use and works in very long…

PX4 Software-In-The-Loop(SITL) Simulation on Gazebo

Jaeyoung Lim Introduction PX4 is a great platform to implement a UAV system based on a opensource autopilot. One of the great features of PX4 is that you can run a SITL simulation(Software in the loop simulation) to simulate your flight on simulation. This is useful as you can check new mission or control algorithms…

External Position Control of a Quadrotor Using USB2PPM

Jaeyoung Lim Overview A USB2PPM interface was developed which enables a PC to interact directly with the RC transmitter trainer port. External Position Control was successfully demonstrated to show that the computer can successfully control real-time applications using the USB2PPM controller. This can be used for sending simple data in long distances (~2km) in a…