Measuring Altitude using BMP280 sensor

[Ravi]

Hi,

    My application requires measuring the altitude with 0.5m to 1m accuracy. So, I am using the BMP280 sensor to calculate the altitude. The sensor is connected to the NODEMCU(ESP8266) and data read using the I2C interface in Arduino IDE. But while testing the altitude varies to 20m even though the sensor is kept at someplace over a period of time(around 6hrs). PFA for the code and image which shows the variation in altitude (MIN and MAX). Please suggest some solution in order to get the required functionality.

[kgoveas]

Hi Ravi,

The barometric pressure measured changes  depending on time of day and the weather itself. 

For what kind of product/project are looking to include the pressure sensor into? The BMP388 is better pressure sensor that the BMP280 for measuring smaller pressure changes. Note that, it will still be affected by the change in weather.

Regards,
kgoveas

[Ravi]

Hi kgoveas,

        Thanks for the reply. My application requires to measure the height of the product placed in a warehouse(to track or locate products in warehouse) which means over a period of time(for example, If I place the sensor at 930meters from sea level for 3 days or more) it should show the same height in order to track it but with current scenario, the height is changing over a period of time even though we place the sensor at the constant position. Using pressure and temperature data we are able to calculate the height but the issue was as you said it will be varied depending on the time of day and the weather itself. So, We can't get the constant height if we place the sensor in the same position over a period of time? Is this sensor serves for my application? or Can you suggest any other sensor which will work for my application?

[o_o]

Long-term altitude tracking requires compensation for weather effect, either with a data connection to weather services, or with a reference device in the same building placed at a known altitude.

Can you suggest any other sensor which will work for my application?
I could suggest 2 solutions:
1) Add a single BMP388 (BMP280 is an older part) base station in each warehouse. I imagine these devices have some sort of wireless connection together.
2) Add an accelerometer, such as the BMA253 (if cost is crucial) or BMA400 (if low-power is crucial) and use the accelerometer to determine in software if the device is moving, or if the pressure change comes from the weather.

o_o

[Bgeof]

Hello everybody,

I want to use a BMP280 to install it in a small aircraft as an altimeter. This sensor is supposed to give the absolute and relative pressure I think.
All the applications found on the web do not talk about the compensation that must be done when the temperature is not standard, i.e. 15°C at sea level, so pressure of 1013.25HPa. Indeed, it seems to me that at each altitude, it is necessary to check that we have the right temperature, this one decreasing by 2° per 1000 feet. If this is not the case, you have to recalculate the altitude with the temperature correction. I didn't find that algorithm. Does anyone know where to find it... or how to find it?

Many thanks in advance,

Bgeof