The SF11/C laser altimeter - awesome performance for $249

With a range in excess of 100m and able to measure over water, the SF11/C is the most cost effective laser altimeter for drones on the market today. Compatibility with Pixhawk and derivative flight controllers and its multiple interfaces including serial, I2C, analog and USB make the SF11/C the easiest plug-and-play solution for altitude holding, terrain following and safe landing.

The SF11/C was developed to handle the unpredictable real-world conditions that sensors face when attached to a drone. Environmental factors including vibration, wind, noise, temperature fluctuations and extreme contrasts in lighting from brilliant sunshine to pitch dark are all managed by the SF11/C, and whilst all this is going on, the SF11/C measures to rapidly changing terrain, giving stable results over wet and dry surfaces without producing false readings.

Tests conducted by the Center for Research into Ecological and Environmental Modeling at the University of St Andrews in Scotland demonstrated the abilities of the SF11/C over wetlands and open water. Their requirement for consistent results under these difficult conditions were easily met by the SF11/C, contributing to important conservation work.

An important characteristic of the SF11/C is its long measuring range. This is especially useful during changes of roll or pitch angle. Data from the IMU is used to correct for geometric effects during such maneuvers, but this only works correctly when there is valid measurement data from the laser. The long measuring range of the SF11/C makes this possible as you can see from the graph below.

The green line is the roll angle, the purple line is the barometric height referenced to sea level and the red line is the uncorrected, AGL altitude from the SF11/C. During tight turns the measured distance increases significantly but the long range capability of the SF11/C keeps the ground clearly in view. 

 

More details about the SF11/C can be downloaded from the website. The SF11/C is manufactured by LightWare Optoelectronics (Pty) Ltd based in South Africa. LightWare has been designing and manufacturing laser altimeters for the drone market for 5 years and is committed to providing high quality products to the industry. The official distributors in the USA are Parallax and Acroname.

Special thanks go to the dev team for their contributions to the driver software and Tridge for his tireless and occasionally incendiary flight testing ;). 

Views: 11668

Comment by Laser Developer on March 12, 2018 at 10:21pm

At the moment the SF11/C has no firmware update capability unless it is returned to the factory. The changes from Version 1.1 to 1.21 are minor and probably will not affect the performance in any noticeable way. 

Comment by Tom in NOVA on March 12, 2018 at 11:30pm

Version 1.1 of the firmware does not have the "long range" option available and I will be using this as a rangefinder for an airrifle scope setup from 40-100m. .  Also it does not have the signal strength showing in the terminal mode,

I found the Version 1.21 update files for the MS Visual Studio project, but it's been a while since I did any Github:

https://github.com/LightWare-Optoelectronics/LightWareDotNET

Comment

You need to be a member of DIY Drones to add comments!

Join DIY Drones

© 2019   Created by Chris Anderson.   Powered by

Badges  |  Report an Issue  |  Terms of Service