Imaging (sensors)

 Hello,I am using the VL53L8CX ToF sensor (I2C) and have encountered an issue. Currently, I’m not using a coverglass, and I have set the sensor to an 8x8 resolution with a frequency of 15 Hz.The problem is that when I run the sensor in an infinite loop, it stops collecting data after a while, usually within 10 minutes, without displaying any error messages.Could you please help me identify the cause of this issue and suggest possible solutions?Thank you in advance!

I'm designing a custom LiDAR sensor for a project and I need a sensor to accurately measure the distance to a small point. I'm looking for an accuracy of +-5mm but the small the better, the maximum range it needs to measure is about 400mm and the minimum range is about 50mm. I would also like a ranging frequency of about 100Hz but that's not set in stone. I've been looking at the VL53 ToF sensors but they all have larger FoV's than I'd like so I have 2 questions:Which ToF sensor would be best for these specifications?Is there a way to reduce the FoV? (e.g. with a small aperture or a lens perhaps)Any help would be appreciated and I'm happy to answer any questions.

Hello everyone,    Recently I tried to use VL53L3CX to accomplish a distance calculating project. When referencing the document of VL53L3CX I found a little strange about the distance parameter.        For example, the note of ranging capabilities table in the datasheet DS13204, shows that "The ranging distances reported are the ones reported by the driver by the parameter called RangeMilliMeter". While in the application note AN5561, it shows that "The ranging distances in the table below are those reported by the driver by the parameter called RangeMeanMilliMeter."        What I confused is: inside the API(VL53L3CX_BareDriver_1.2.10), I could not find the driver parameter named "RangeMeanMilliMeter".While "RangeMilliMeter" could be found in the structure VL53L3_RangingMeasurementData_t. So if there has any difference between these two parameters? If yes, how to use the parameter RangeMilliMeter and what's its definition

I'm using the full API for the VL53L1 ToF sensor. The project is pretty simple as I'm using 4 sensor to measure distance connected on an I2C of an STM32F091.I'm optimizing the code and I'm come across the VL53L1X ULD API (Ultra Lite Driver Application Programming Interface) STSW-IMG009.From what I'm seeing most of the function I'm using:VL53L1_StartMeasurementVL53L1_GetMeasurementDataReadyVL53L1_GetRangingMeasurementDataVL53L1_ClearInterruptAndStartMeasurementXNUCLEO53L1A1_ResetIdVL53L1_SetDeviceAddressVL53L1_WaitDeviceBootedVL53L1_DataInitVL53L1_StaticInitVL53L1_SetDistanceModeVL53L1_SetMeasurementTimingBudgetMicroSecondsVL53L1_SetInterMeasurementPeriodMilliSecondsCould be replaced with the ones available in the ULD API.The only thing I can't understand is how to edit the Dev structure. I'm currently usingDev->I2cHandle = &hi2c2;Dev->comms_speed_khz = 100; //400Dev->comms_type = 1;Dev->I2cDevAddr = 0x52; // default ToF sensor I2C addressFrom what I'

Hi ST,Using the vl53l1x in our devices we are finding some cases of unexplained sensor distance changes.  Large changes. We use the sensor in a contained/controlled environment.  A bin -- the sensor is used to measure distance to items contained in the bin.We have seen some cases where the sensor behaves normally and then,  unexplained,  it spikes way up.  From 100mm to 2meters  measurements for instance. Powering off and powering on brings it back to normal.We are unsure where to start looking here so wanted to ask first here.  What might be possible causes of this?Thanks,Will  

The device does not output the data in a sudden. And it has no effect to press the RESET button. When I try to re-flash the board, the available memory of the flash only remains 8KB. Even the total memory is only shown as 32KB on PC, much less than the normal size which is 512KB. So I cannot copy the BIN to the flash according to the USER-MANUAL as usual. How to fix this?

Hi, We have a board featuring 5 VL6180X sensors and I noticed some oddities regarding the initial offset and scale in the latest production run:Some sensors are unable to measure any distance below 15mmThe ranging linearity between different sensors is +/- 10mm (taken as the delta between a 20mm and a 68mm measurement to a matte aluminium plate).Initial offset is varying +/- 10mm The initial offset appears to be roughly in spec with the datasheet (Table 18. Ranging specification), although we have quite a few sensors at the maximum offset (and in the datasheet this is after 3 reflow cycles, we only have 1).The linearity is far worse than what I see in "Figure 6. Typical ranging performance".The largest issue for us is the inability to measure below 15mm. Some sensors simply register 0mm (4 boards out of a batch of 30 had this issue).I was wondering if this is the expected behavior of the sensors, or if we're doing something wrong in our design/production?Regards,SytseFYI, our

Hi!I've since given up on utilizing VL53L1X for liquid level measurement. @John E KVAM had previously reccomended me to use instead the VL53L4CD sensor for this sort of application (small recipients with water), and I plan to ship it next week. But I've also read about VL53L5CX which has the advantage of reading liquid level even when angled at about 15° due to its wider FoV.Is there any other ToF sensor that should perform well for this kind of scenario that I'm not aware of? Even if being overall worse but having an specific advantage like VL53L5CX.Thanks in advance!Edit: I've noticed now that the VL53L4CD is out of stock on both stores I could ship from, but VL53L4CX is available. From this forum post, I gathered that I can run the ...CD software on the ...CX, but do they have any other difference besides processing power?

Hello ST team.I am operating the VL53L1CB sensor with zephyrRTOS, I reach distances to four meters without problems, in addition to measure distance above them (eight meters top in ideal conditions), all this in ROI.I am working with the manual UM2133 and I have doubts about the calibration, I have a crystal covers (bought by aliexpress) and I did the calibration proposed by the manual, it has some crosstalk interference, it works with intermediate accuracy and precision.Do you have any manual that explains in more detail about the calibration (refSPAD, crosstalk, offset)? especially the point “6.2.6 Setting crosstalk calibration data” that makes in detail the parameters and how it affects the sensor.The purpose is to improve accuracy and precisionBest regardsThanks!

Hello, I'm currently working on a project with a VL53L8X sensor.When I installed this product on the ceiling, the data of adults passing by is well observed, but the data of children passing by is not. I understand that this is a physical limitation that comes from the 8by8 array.Is there a software solution to this?Thank you

I have 5 VL53L8CX on the same I2C bus.I need to set the LPn pin HIGH of the sensor I want to change address.But the problem is that I can also change the address when LPn pin is low as well.Also I also don't know how to scan I2C addresses in only one sensor when all other also reply as well even though only one sensor has LPn pin set to HIGH.Can I not disable I2C with the LPn pin or am I missing something?LPn pin datasheet:Enables communication. Drive this pin to logic 0to disable the I²C communication. Drive this pinto logic 1 to enable the I²C communication. Thispin is typically used when you need to changethe I²C address in multidevice systems. 

I am trying to use Satel VL53L8 Cx over Arduino due . The library I am using is stm32duino VL53l8cx but I never get any result .Connections were as per the expamples but it did not work.Is there a library I can use for this . I have earlier used VL53l5 but that never created an issue

I hope someone can help me with the accuracy of my VL53L1 sensor. I can’t get the sensor working accurately above 40cm. I am working on a hobby project and want to use the sensor to avoid obstacles. The board I use is not an VL53L1-SATEL. It’s from an other manufacturer. I tried different api’s. The most recent full api and the ULD from ST. I even tried the Adafruit api for this sensor. All the api’s are producing more or less the same results. Is there something I could test to figure out what’s going on? 

I am looking into the VL53L4CD TOF sensor but find the specifications on distance accuracy at 10 cm (or perhaps in range 5 - 20 cm) to be murky at best.  I need to be able to determine distance to object with accuracy of 0.02 mm (0.001 inches) at this distance and be able to determine if object has moved in or out by that amount or more.  Can this device produce that kind of accuracy? Other posts here make me think not, that all it can do is about 1 mm.Also, the ST introductory webinar mentioned higher resolution project 55H2 if I heard it right. Can you provide any insights on that? Or suggest another product that can provide the accuracy / precision that I need, please.Initially planning to use Arduino for the CPU processing.Thank you.

Hi,I have an X-NUCLEO-53L1A2 and a NODE_F401RE.The VL53L1.exe GUI is unstable and frequently freezes, but I could at least perform most of my experimental measurements (including MultiZone Ranging 4x4).However, when using MultiZone 10x10 Ranging, the GUI constantly crashes. During calibration, the following message appears:  Is this a known issue? What could be the problem?What do I have to do to be able to use the devkit?Thank you very much for your supportRegardsStefan@John E KVAM 

We have two VL53L1X sensors side by side. Both have gilizmo cover glass and are placed 140mm from a 8.5x11 sheet of mat grey paper. Running the calibrate offset function returns 2mm for sensor one and 6mm for sensor two. Following this the Xtalk calibration function is called this returns 37333cps for sensor1 and 52562cps for sensor2. Measuring distance after calibration shows the sensors are now way off and differ 2-3 inches from each other.  My question is what could be going on to get such high values for Xtalk when we have ideal cover glass and placement?Do we want the SPAD ROI to be 16x16 when we run the calibration? currently we have it at 4x4, 200ms of timing budget, and 200ms of intermeasurement period. The sensors are in a dark room away from an external sources of IR light.  

An anonymous customer was trying to get the best possible range accuracy with a VL53L5 sensor.  His temperature range was from 25degrees C to 50 degrees. This was his plot with no temp cal.  After calibrating between the ranges he got: These plots have different temperature ranges and scales. But between 25 and 35 degrees, the top shows a drift of 10mm whereas the bottom shows a drift of 1mm.  He tells me the calibration takes a while which is a reason to skip it, but if you really need the accuracy, it's worth trying.   He did not show me what he was doing, but I'm betting it's:   /** * @brief This function is used to set a periodic temperature compensation. By * setting a repeat count different to 0 the firmware automatically runs a * temperature calibration every N frames. * default the repeat count is set to 0 * @PAram (VL53L5CX_Configuration) *p_dev : VL53L5CX configuration structure. * @PAram (uint32_t) repeat_count : Number of frames between

Dear forum,I try to understand the bin shape of the VL53L8CX / CH sensor calibration buffer while evaluating different sensor cover and their influence on ranging. Using the example8 file from the ULD driver the shape looks more or less always the same (as eg. shown by @John E KVAM ) for most cover glasses I used. Nevertheless doing the math with a bin size of 3.75 cm the light path must be in range of ~40 cm, which seems to me highly unlikely with a 1 mm cover glass placed in 0.5 mm distance. Moreover I realized that the calibration buffer yields 144 bins whereas I read somewhere here that there are only 128 bins for ranging.Perhaps someone can elaborate on that a little bit.Thanks!

I am currently working with the VL6180X proximity sensor and would like to inquire about its long-term performance characteristics:      1. What is the expected Light/Luminous Depreciation time frame for the VL6180X's VCSEL source? Could you                provide any data regarding its lumen maintenance curve or L70/L50 specifications?     2.How does Light/Luminous Depreciation affect the sensor's performance over time?        Specifically:                 1. Does it primarily manifest as a reduction in return signal rate?                 2. Are there any observable changes in measurement accuracy?                 3. What are the typical indicators that Light/Luminous Depreciation has occurred?      3. Are there any recommended compensation strategi

I’m using a VL53L5CXV0DH/1 sensor in my current setup (see pictures). The goal is to detect a ball rolling between the sensor and the background. The red box is about 12cm apart.The settings is 4x4 for speed, i also noticed that 60 is not the highest scan frequency in code : status = vl53l5cx_set_ranging_frequency_hz(&dev,60);if i set 120 this works too, while scanning seems to be lot faster and just as accurate, why is 60 defined as maximum in the datasheet?However (even at 60), I often see target_status = 255 for 3-4 pads, without the ball passing and wonder why this happens. When this occurs, the distance information is apparently correct but the datasheets states that the distance readings become unreliable, and I want to ensure I get the most accurate and dependable measurements.When the ball passes i see 255 in even more status records.What could be causing this issue?Additionally, I’d appreciate any advice on settings or adjustments to improve detection, especially

I need to calibrate a VL53L4CX and have been reading UM2923. The functions described do not seem to bear any obvious relationship to the functions in the STM32Cube middleware which was generated for my project, which I find confusing. I it is not clear which functions I should be calling in order to satisfy the flow charts in UM2923. I have found essentially no other useful information about this device or its specific set of registers. I'm usually a huge fan of ST devices and documentation... The first sticking point is how to properly understand what to do with calibration settings. Am I supposed to store them in my own flash somewhere? That seems to be implied by UM2923. I can do this, but imagined the device would have its own NVM storage on board, since it is calibrated in the factory anyway. Is this the case? I thought so because the wrapper function VL53L4A2_RANGING_SENSOR_OffsetCalibration() ends by writing a data structure over the I2C interface from a function called VL53LX_s

Hi everyone,I know there are 25 and 35 degree detection angles of VL53L3. I am aware that this situation is a mechanical situation. But I want to make a timing gate and find people's speeds. We have submitted our product to reliability and validity tests, but the detection situation at 25 and 35 degree angles prevents us from getting this reliability and validity tests. We want it to detect when the target is right in front of (linear detection) the sensor. Is there a software solution for this?  

Hello again!I've been trying to measure water level using the VL53L1 sensor and reading forum posts on it, and I've gathered that RefSPAD calibration isn't really recommended anymore.From my research on the topic, I know that water reflects only 2% of perpendicular incident light, with the rest getting transmitted and also that the transmitted rays will be fully absorbed at a minimum water level of 10cm.I was wondering if doing the RefSPAD calibration utilizing the VL53L1 (with a cover glass) leveled parallel to a water suface from a body deep enough to absorb all transmitted laser could end up improving the sensor's results by giving more weight to SPADs more likely to detect those perfectly reflected photons.Thanks in advance!

Hello,For the vd55g0, you provide a kernel driver and device tree as source here: https://www.st.com/en/embedded-software/stsw-img505.htmlYou also provide a libcamera integration stack (STSW-IMG505_LCAM), but this is closed source, and only the libcamera-base.so and libcamera.so files are provided via the .deb package. This makes it such that we cannot work with the libcamera source or custom applications, unless we use your pre-compiled libcamera libraries.Could we please get source code for the changes, per LGPL 2.1, which libcamera uses? Or, for now, if this takes some time for you to do, please just the camera helper file would be massively helpful. This is likely called "camera_helper_vd55g0.cpp" inside of "src/ipa/rpi/cam_helper/". Of course we can write our own but we chose this path for ease of integration and speed.This would greatly assist us in integrating your sensor to our product.Thank you! We would greatly appreciate it.

I bought a STEVAL-55G0MBI1, which is the VD55G0 S-Board eval kit. Trying to output the image to my PC, nothing is coming out.  What could be the issue with my setup?