Our IARC Mission 7 team this past year used an RPLIDAR A2 made by Slamtec for obstacle detection. For a little background information, the drone flies in an open gymnasium and must avoid four moving ground robots with tall PVC pipes on top.
The installation and setup process were fairly painless. We have used both the NVIDIA Jetson TX1 and TX2 with this sensor. The default configuration of Linux4Tegra does not include the kernel module for communicating with the CP210x usb-to-serial converter included with the RPLIDAR. To set up this kernel module, we followed the instructions here.
After that was done, everything worked flawlessly with the ROS packages provided by Slamtec here.
We had no problems with noisy or invalid data coming out of the sensor; we were easily able to cluster the data into individual obstacles that could then be fed into our obstacle avoidance code....
For our 5kg custom autonomous quadrotor built over the past year, we used KDE Direct ESCs, motors, and props. Specifically, we designed our propulsion system to provide approximately 10kg of thrust using the following combination:
- 515Kv, 535W Brushless Motors (KDE2814XF-515)
- 35A ESCs (KDEXF-UAS35)
- Triple-bladed 12.5x4.3 Carbon Fiber propellers (KDE-CF125-TP)
The ESCs were fantastic and incredibly responsive. The synchronous rectification and regenerative braking features do feed large transients back into the system, but the only problem this caused occured when we had a connection (external to KDE’s electronics) between our control electronics and our motor power system. We were able to diagnose the problem with KDE’s help, and adding an opto-isolation barrier completely solved any problems.
The motors were also very reliable and well-constructed. We had one extremely bad crash from approximately 15m which broke the bearings on one motor, but they have otherwise been good....
We are happy to announce that one of our teams competed at the American Venue of the International Aerial Robotics Competition last week, and won an award for Best System Design. Although no team was able to fully complete the mission, we did achieve the highest overall score out of all the teams at the American Venue.
A brief slide presentation summarizing our design can be found here. A more thorough description of the successes and flaws in our approach will be posted on this website shortly.