Low cost, medium range LIDAR testing - LidarLite vs TF02-Pro

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A lot of good info, thanks for the link. Seems that LIDAR is great for alt hold and obstacle avoidance but a PX4 flow sensor is required for position hold. From what I’ve read, this flow sensor works independent of GPS but some work was
underway to combine the data from the flow sensor and GPS so that both systems work together to achieve a positive and stable position hold. Do you know if this has now been incorporated in Mission Planner or is it still in the works?

Will

Mail](https://go.microsoft.com/fwlink/?LinkId=550986) for Windows 10

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Hello,

PX4Flow works as a velocity estimator and it can serve as a GPS backup in case you loose the signal for a short time. But the switching mechanism is not fully functional and there is some work being done ATM th optimize the switching , look for Lsne Switching in the forum.

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I see a “FLOW HOLD” mode has been added in Mission Planner. I’m a little confused as it indicates that it does not require a rangefinder. Based on your experience, what optical flow unit would you recommend for use today and would you combine it with a LIDAR?

Will

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PX4FLOW is still the best as it is completely integrated within EKF estimator using the rangefinder distance (altitude) for precise measurement of velocity at various altitudes

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Would you recommend using a PX4 with a sonar rangefinder or without and utilize the LIDAR for altitude?

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Sonar signals get washed out by airflow
Lidar are best

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Thanks for your patience and insight, very much appreciated. Weather is looking good here in Toronto, time to dust off the gear.

Will

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I use TF02 on serial port 4 (GPS 2) of Pixhawk cube black. when turn on the vehicle, both GPS 1 and GPS 2 port power is shut down, other parts works.

What is problem?
Thank you

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We generally power the LIDAR on a dedicated UBEC (3-5 Amps) and Lidar Lite recommendation is to add a 470 uF capacitor on the Vcc.

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Thanks, Yes, the reason is my Cube supply is only 0.5A. I fixed this issue. use extra power supply 5V for TF02.

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Hello ppoirier,
I need your advice for my copter that can not arm after installing Benewake TF mini. The reason is because RTL Altitude above Range Finder max. range.
RTL Altitude is 15m and Range finder max. is 5.5m.

Thank you.
I created a new post here:

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Thanks for this blog- I had previously read the that the Lidar lite v3 required 680 uf and I wired accordingly (actually 690) and powered via mauch pc for 5.3 volts and could confirm power out through to lidar. bit I get no varification in status menu of functionality. I will try 470 and hopefully this will work … my other question i2c address do I need to add one for ising only a single i2c device?

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Hello
It all depend on the Ubec capacity , you may need cspacitor on low regulated devices.
As for I2C address , the default adress is just fine just plug it in FC and enable rangefinder on Mission Planner, reboot and check on rangefinder values

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Ok thankyou, If I go to rangefinder setup in MP I cannot change values-- I can change them fine in MP parameters so this is fine. Also are you suggesting that Capacitor may not be required at all with stable 5.3 volts from Mauch PC. The default I2c address where do I find this? - If not required for now It could be useful for future reference like adding additional Lidar.

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Capacitors are highly recommended, I generally use them on this lidar as it help stabilizing the distance estimate

As for changing the garmin I2C address you can use an arduino with the example code available on garmin github

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Thankyou, so with my testing to date I get range finder values of zero - Latest MP and Copter 4.1.stable (2?). Cube orange Is there another way to determine if lidar is being recognised I can see through small gap at connection on lidar that I have a pulsing red light (led / laser). Now with 470uf capacitor. To confirm Sonar also 0 output

RNGFND_FILT 0.5
RNGFND1_ADDR 0
RNGFND1_FUNCTION 0
RNGFND1_GNDCLEAR 20
RNGFND1_MAX_CM 3500
RNGFND1_MIN_CM 20
RNGFND1_OFFSET 0
RNGFND1_ORIENT 25
RNGFND1_PIN -1
RNGFND1_POS_X 0
RNGFND1_POS_Y 0
RNGFND1_POS_Z 0
RNGFND1_PWRRNG 0
RNGFND1_RMETRIC 1
RNGFND1_SCALING 1
RNGFND1_STOP_PIN -1
RNGFND1_TYPE 15

Thankyou for your support on this topic

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Hello,
I would like to know would you recommend the TF02PRO for making models of buildings? I want to create a model of our school, but I’m not sure which LiDAR sensor would be appropriate for this purpose. We kinda have high buildings up to 13 floor and a lot of windows. I’m not sure that TF02PRO can handle so much sun reflection. Thank you in advance!

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Hello,

I don’t think that these cheap basic Lidars can do the job as they are not working well with high reflectivity like glass or water. You can give it a try but I guess You will need a much more advanced device for this task

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I see. What if I try the TF02Pro on an ordinary building with less reflectivity? Because I don’t think I can afford a more expensive sensor…

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I am setting up a high-precision landing system and intend to use the range finder a barometer over-check for the altitude reading.

I have followed the setup instructions for the TF02 found here.

However, I am using a TF02-Pro for my setup. I noticed, among other things, that you set RNGFND2_TYPE to 8 (instead of 19 as per the instructions in the link). RNGFND2_TYPE 8 is given as LightWareSerial in Complete Parameter List — Copter documentation.

Furthermore, on Mission Planner, which is how I am setting these parameters, I don’t see RNGFND1_MIN_CM,
RNGFND1_MAX_CM,
RNGFND1_GNDCLEAR

I do not for a minute exclude the possibility that I am being thick and missing something obvious here.

Would you care to explain my observations please?

(As an aside some bench-testing has shown the range finder to work fine for a ~2m range. I have not been able to test any further than that, I expect the max range to be limited to that of the TF02, but cannot yet confirm this).