Can you apply an equation to a device "parameter" and show the result?

AnthonyBarone

I am trying to get a nice and “user-friendly” battery level indicator shown for my dog’s tracker in Petovik.

My device does not output battery percentage directly, but does output battery voltage via a parameter called “pwr_int”. I have this currently shown on the main Petovik screen, but would much rather have the actual battery percentage.

The manufacturer says that 4.2V is full charge, 3.3V is empty, and in between there is a linear relationship between battery voltage and % battery remaining, so I can convert battery voltage to % battery remaining via a simple transformation:

<% battery remaining> = ( <battery voltage> - 3.3 ) * 111.111

Is it possible to have Petovik run “pwr_int” parameter through the above equation and display the output instead of displaying the raw battery voltage?

kula

Dear AnthonyBarone,

Thank you for your suggestion, we will analyze and discuss it with the team.

Could you also please specify the model of your device (device type)?

AnthonyBarone

Thank you for the reply and for taking the time to consider adding support for this!

The device is a Mictrack MT710. In Petovik it is unit 5068653.

NOTE: the device is quite new (started shipping ₁ month ago) and your system does not have a “mictrack MT710” device profile, so in Petovik I am using the “mictrack mt700 (legacy)” device profile.

Here is a link to the main page for the product from its manufacturer.

Here is a link to the mictrack support article that shows which battery percentage corresponds to each possible battery voltage.

kula

Dear AnthonyBarone,

Thank you for the information provided.
We will try to contact the manufacturer for more information to implement your request.

If you have been in contact with the manufacturer and have their contact information, we would appreciate it if you could share it with us.
You can provide this information to us by email support@gps-trace.com

Thank you in advance!

TomD

You can actually do this in flespi. Sign up for a free flespi account and add your device to flespi. Create a channel in flespi with the protocol of your device to receive the data and point your tracker to this flespi channel. Create a PVM plugin in flespi to modify the data and add your device to it. Create a stream in flespi with “ruhavik protocol” to stream the modified data to petovik (or ruhavik) and add your device to it. In petovik (or ruhavik) select the flespi gateway option for your tracker. Here is the PVM plugin code I use to convert voltage to battery % (assuming 4.2V is 100% and 3.3V is 0%):

// % = sum(voltage to 3.3v) / sum(4.2v max charge to 3.3v) * 100
(.battery.voltage - 3.3) * (.battery.voltage + 3.3) / (4.2 - 3.3) / (4.2 + 3.3) * 100 ==> math.round ==> #battery.level

The “correct” formula probably depends on the chemistry of your battery. Alternate formula here: https://electronics.stackexchange.com/questions/435837/calculate-battery-percentage-on-lipo-battery

You can also do lots of other cool stuff in flespi with a pvm plugin, as well as use the proxy server option in flespi to send data to multiple targets. That way you can still use the native tracking app, while also sending data to other targets like ruhavik or petovik.