MEMS (sensors)

Hello,I use the gyroscope of an LSM6DS3 to command the rotation of a robot. I read the different axis with a 50ms period and I use the gyro internal timestamp to get a precise timing of each sample and I integrate the angular speed using the trapezoidal rule (https://en.wikipedia.org/wiki/Trapezoidal_rule) to get my angle in degrees.The problem here is when I place the gyroscope on a test bench and drive two rotations of the same value in two directions, I experice a shift of about 10° per sequence.What can be the cause of the shift here? Am I missing something ?sincerelyps : I of course calculate an offset to make sure the data i read from the gyro ar centered in zero

Have you ever wondered how to build a working application that consumes little and costs little, but that guarantees high accuracy and meets your desiderata? If so, this series of posts will help you implement your own application with ST sensors, in particular motion sensors, by simply interfacing them with an mcu (STM32) of your choice and leaving all the data analysis and optimization work to existing libraries.To make the examples concrete, an expansion board of the standard X-Core family of ST as hardware reference design will be proposed as it already has a test GUI for a prototype test of your app!So... let's start!

Hi, i'm testing H3LIS331DL and the configuration is as below:Normal mode, 1000Hz sampling, +/-400gSensor data is read by MCU under 1ms timer. If sensor is placed upside or downside, the output value of is verified to be normal (+1/-1g value).However if apply a small click on the PCB, the output value can be over 100g. Refer to attached figure which captured by logic analyser, the output value for x/y/z axis are 0xFEC0, 0xF1E0, 0x7FF0 (decimal value would be -320, -3616, 32752). The resolution is 12.208mg. Hence the acceleration are -3.9g, -44.1g, 399.8g. I think 399.8g would be too high... I've tested some samples but same result. What's the possible cause? Thanks.

I Refered to Page 25 ,7.1 of the Document and Used of MEMS Library without sample applications for XNUCLEO-IKS01A2 with NUCLEO-L4R5ZI. in the platform setting there is no BSP_BUS_DRIVER ,i2c。another problem is that BSP_USART has no solution. Who knows how to solve this problem?thank you.my setting screen pdf doc screen

I have a problem with this sensor configured for 2g scale and interrupt on INT1 for click detection.If I set threshold register in a range 5 to 7 I receive a lot of interrupts as soon as the sensor is slightly inclined on X or Y axis.Please see below I2C dump of registers configured.NOTE: This question and answer originated from a customer support case which was handled by us. We regularly review support cases and add any helpful ones here for all to benefit from.        

Hi to all,I'm doing a Keil project using the MotionFX library contained in the xCube-mems1 v6.0.1, the project run a STM32F407ZG.I've enabled the CRC clock, I've added the library "MotionFX_CM4F_wc16_ot.a", I've enabled the FPU unit.I can build the project, I can Initialize the library and it gets me a valid lib version, but the sensor fusion algorithm doesn't work, it return 0.0 for any euler angles, and for any gyro bias valuesThe code works with Atollic, but I need to use Keil, any suggestion?

hello everyone,i am working with stm32f401re microcontroller and STEVAL-IDP005V1 industrial sensor. I follow the below link to program the STEVAL-IDP005V1 .when i copy the .bin file into STM32F401RE i got the error like "The application file format is unknown and cannot be parsed and/or processed",please help me to fix this.https://www.st.com/content/ccc/resource/sales_and_marketing/presentation/product_presentation/group0/47/a2/91/a0/fe/ca/42/89/steval-bfa001v1b_getting_started_guide/files/steval-bfa001v1b_quick_start_guide.pdf/jcr:content/translations/en.steval-bfa001v1b_quick_start_guide.pdf

I want to read a X,Y,Z values from the LIS3DH Accelerometer(SLAVE) and nrf52832 SOC(Master) using Mbed OS platform.Can anyone have a example program for this?Please share with me...Thanks & Regards, Yuvaraj

Hi everyone,I'm trying to use the machine states of the LIS3DSH (on a STEVAL_MK109V3 in the ST unico utility) to implement a mechanism to provide an interrupt when a series of movements happen in a defined time slot, to trigger a trip start event, and get the interruption of the movement after accelerations stops for another defined time slot.I've realized the attached state machines, but I've noticed, after some attempts, that after some movements, less than the requested for trigger trip start, and stops moving the sensor, the machine states stops execution changing the CTRL_REG1 and CTRL_REG2 value.I'm measuring movement in DIFF mode, and using the state machine 2 called from the state machine 1 by ssync command.Thanks for all the support, and suggestions

Dear All: I have a project to read LIS3DH data and use STM32F745 MCU to access 3 Axis of LIS3DH data. After initial LIS3DH control register(CTRL1_REG=0x47 /*set ODR as 50 Hz and enable Ax Ay Az....*/ and CTRL4_REG=0x88 /*enable block data update(BDU) and High resolution Mode ..... */), we can get the correct Y and Z Axis of data. Nevertheless, we can't get the correct data of the X axis ,always in 0x8090, when the status_reg (0x27) is 0xff. What is wrong with the X axis of LIS3DH? Can we do next step. 

Hello All,Good day!I got three boards placed close to each other but the humidity readings on three boards varies. Say, 1 board has a humidity reading of ~50 %, the other has ~60% and the last one has ~70 %. I'm not testing it on a closed environment but still it seems the readings are incorrect since the sensors are placed close to each other.I'm using FLUKE 971 Temperature and Humidity Meter as reference and has a value of ~50 %.Attached herewith is the file that contains the calibration and actual raw values.Also attached is my source code. Please let me know if you've found errors on it. :)If this is a bug on the chip itself, can this be solved via CTRL registers?Regards,Elton

I have instaled the "ST BLE Sensor" on my smartphone and made some data collecting using accelerometer sensor. I have seen on the APP presentation that is possible to choose the frequency but I didn't find this option in the APP. I am seding a image of the APP section that show the option. If somemone could help to find this option, it will help me a lot on my researches.Thank you.

I use a LSM303C magnetometer sensor on an Android platform.Sensor works fine, however automatic calibration (hard and soft iron) does not work. I checked it using an Android app displaying magnetic field vector in 2D, for both calibrated and uncalibrated data. With my platform (Android 5.0 and ST MEMS driver + Android framework), calibrated and uncalibrated data are the same (red and blue text boxes), so it seems that there is no calibration algorithm running :The same app tested on a Samsung S7 show calibrated and uncalibrated data after a full 360° rotation on Z axis, uncalibrated circle (red) is correctly shifted to calibrated circle (blue) :

I want to program the mcu STM32 STEVAL-STLCS01V1. I have the STEVAL-STLKT01V1 Sensor development kit and i've read that i can mount the STLCX01V1 on the Arduino Uno board, mount the STEVAL-STLCS01V1 on the STLCX01V1 board. and then use the Arduino sketch IDE to program the STEVAL-STLCS01V1 micro-controller.I have some follow-up questions:1. Am i correct? can i do that (program the STEVAL-STLCS01V1 using the Arduino Uno and the Arduino IDE, when i connect the board as i explained above)?2. If i can program the STEVAL-STLCS01V1 using the Arduino Uno IDE, do i need to add some libraries to my sketch? or do something else before i write my code (like i write any other code for Arduino)?3. Do you have more instruction that i need to know when i program the micro-controller with the Arduino IDE?Thank you very much for your help,Reshef Finkelstein

Hello,I'm actually work with sensorTile for vibration analysis. I'm using defaut demo library ALLMEMS1 V340 and communicate by Bluetooth. My first data collection are very well but now i want to change my sampling periode from 52Hz (defaut Acc sampling time 50ms) to higher. I know possibilities of the sensor and found the table, but i dont found the setting value for change it. I turn around for couple of hour...I use AC6 to read library, and programming sensor with an nucleo board L476RG and STM32 cube.Thanks for you help

 P4SEL |= 0x06;              // Assign I2C pins P4.1, P4.2 to USCI_B1 UCB1CTL1 |= UCSWRST;           // Enable SW reset UCB1CTL0 = UCMST + UCMODE_3 + UCSYNC;   // I2C Master, synchronous mode UCB1CTL1 = UCSSEL_2 + UCSWRST;      // Use SMCLK UCB1BR0 = 12;               // fSCL = SMCLK/12 = ~100kHz UCB1BR1 = 0; UCB1CTL1 &= ~UCSWRST;           // Clear SW reset, resume operationret = lsm303agr_read_reg(ctx, LSM303AGR_WHO_AM_I_A, &ACC_Data_Raw[0], 1); How do I define ctx?

Hello everyone,I am conducting some tests with the STEVAL-BFA001V1B and STEVAL-IDP004V1 evaluation kit together with the STEVAL-IDP005V1 GUI software available on STSW-BFA001V1.But I need to make some changes in the STEVAL-IDP005V1-GUI software, the source files for this softaware are made available and open for changes?I am very grateful for any help or advice.

I don't do it betterhttps://community.st.com/s/group/0F90X000000AXrvSAG/share-your-activities

All values on the axis Z are multiples of 256. If you rotate the gyroscope(lsm6ds3) on an axis with angular velocity <256, the value will be 0. I do not observe this on other axes. The values from the gyroscope are shown in the attach figure. I read using the standard library: link. Code that reads data:lsm6ds3_gy_flag_data_ready_get(dev_ctx, &reg);   if(!reg)   return 1;     memset(data_raw_angular_rate.u8bit, 0x00, 3 * sizeof(int16_t));   lsm6ds3_angular_rate_raw_get(dev_ctx, data_raw_angular_rate.u8bit);   for(int x = 0; x < number_axis; x++)   angular_rate[x] =   data_raw_angular_rate.i16bit[x]What is the reason for this beh

Hello, I installed the latest driver version Unico 8.0.0. Now my board is shown in the decive manager.Ready to use.. Everything looks good.Now I am trying to update the FW in the STEVAL-MKI109V3 board. First I pressed the BT2 Button and pluged the USB into the Laptop(Win7 and Win10). The blue LED (D6) is on, but there is no available DFU Device in the DfuSe Demo (v3.0.5). I noticed that, when I unplug the device and replug it without pressing the BT2 button, the LED (D1) no longer blinking as it did before. As if I was stuck in DFU mode.If I press the BT3 vor reset the LED (D1) is on for half a second. does anyone have any idea what this could be or how I can update the FW?Best regards,Chris

Hi,I have a jar lid which is equipped with LIS3DH accelerometer. The accelerometer is placed in the PCB such that the top layer of LIS3DH will face the sky in normal position. The jar has a groove for holding the lid and we need to put the lid in the groove and rotate it horizontally to lock it in. I want to use the LIS3DH to detect if some one is trying to open the lid. He/She will have to turn the lid horizontally in groove in the opposite direction to unlock it. Basically I need an interrupt to be triggered when the lid is rotated horizontally. Can anyone suggest the I2C register settings for detecting this?I tried many combinations but most of them are generating interrupt when there is a tilt in vertical position. If I keep the device horizontally and keep rotating it without tilting no interrupt is getting generated.I tired the following settings:CTRL_Reg1 - 0x57 - 100HZ with All Axes EnabledCTRL_Reg2 - 0CTR

STM32L476LSM6DSMEXTERNAL INTERRUPTACCELEROMETER TIMESTAMP

Hi,I have couple of question on LIS2DH12TR .I'm trying to interface with CC1310 Custom Board.1. As per the data sheet it says it doesn't need any manual calibration since factory calibration already done.( Previously have used MPU6050 didn't know much about calibration and got to know this MPU6050 has to be calibrated before use) So this LIS2DH12TR need to be calibrated before first time use?2. I have read this sensor has an exceptional feature that sleep to wake-up and vice versa.In my case sensor there'll be some threshold value set for vibration if there's any change in threshold value it will be sent to main controller and data will be sent over the RF.As i assume this sensor has to be in wake-up mode all the time.But in case of sleep mode, how will it(sensor) come back to the wake-up mode are there any external timer required to do so?3. Since I'm not good at coding, Are there any example code for interfacing LIS

The actual sampling rates deviate from the published. For example and ODR of 25Hz is actually ~30Hz. Is this typical? We did not notice this on the IIS2DH part. I expected some variance from the desired rate, but is every device going to vary this much?

I'm seeing some very odd behavior on the LSM6DS3. It works "most" of the time, but seems to randomly change its own settings from time to time. Before we get into that, though, I'd like to ask about the timing of INT1 when driven by the DRDY signal.In section 4.3, page 37, the appnote says:That's pretty explicit: DRDY should be deasserted when register 0x29 is read. At the bottom of this figure you can see that it illustrates the trailing edge of DRDY at the *end* of the X axis data transfer, which makes sense because X's data is in registers 0x28 and 0x29.Now look at what the LSM6DS3 actually does on a scope: