Designing a 3G Foaling Alarm and GPS tracker


The design requirements : 

Originally this device was intended to be a foaling alarm prototype with a GPS tracking option to be used in Australia. Foaling alarm is a device used to detect and alert the horse owner when the horse is about to give birth to a baby so that the owner can take proper care and precautions to keep the horse (called mare) and the baby(called foal) safe.


Foaling Alarm : Most of the foaling alarms today use either of the two techniques to detecting foaling,

1) The Surgical method,  where the alerting device is surgically attached to the mare to detect the baby (foal) coming out. The movement during the foal coming out activates the device and it in turn sends the alert message to the owner informing that the delivery is about to occur.
2) The Non Intrusive method of detecting whether the mare is about to give birth by using the position and orientation of the device attached to the horse’s body. This method is safer and uses orientation and motion sensors to detect whether the mare is sleeping or standing etc. Because, When the birth is about to happen, the mares tend to lie down and this can be used as a signal to detect and alert about the foaling. 

So, to detect the orientation of the horse/mare we introduced a 9-axis motion sensor into the design which uses sensor fusion and gives out the absolute orientation of the device with respect to earth. By attaching the device at appropriate place and using the orientation values given by the MEMS sensor, we can find out if the horse is about to give birth and alert the owner by a SMS, Call, Siren or a Push notification etc.

GPS Tracking : The device should also have a GPS tracking feature where we can see where the current location of the device is. We wanted to keep the device design to be as versatile as possible so that it can be used to track animals, people or assets including vehicles. That’s why we added a external GPS antenna interface for SIM5320 and a internal antenna GPS module SIM39EA also. 


The challenge : 
Australia has a strange set of operating frequencies. I thought they followed whatever USA did, But here they are using something very different. The bands are not among the standard bands of Europe, Asia and America. So most of the modules which work in USA (like SIM5320A) will not work in Australia because i found that the Australian biggest network provider Telestra uses a 3G frequency band that is xx MHz which is not supported by A or E series modules of SIMCOM. The modules which work in Australia are having J series for SIMCOM like the SIM5320J or SIM5360J and for Quectel , its UC15-T. 


This is how the first version of the board looks : 


My obervations so far about the SIM5320 module :

The SIM5320 netlight LED blinking pattern is very unlike of other SIMCOM modules. it stays stable when searching for network and starts blinking when it acquires network.

The  SIM5320 modules power consumption is higher compared to SIM800 module. It definitely is power hungry, as it drained a 400mAH battery in no time on continuous update.


The GPS functionality : 
We tested the GPS functionality of the device using MQTT over TCP update mode, The device was updating to the server at 5 second intervals and here is a ping capture on Google maps when we took it out for a ride on my motorcycle. 

 

This tracking view is using the onboard SIM39EA standalone GPS module.
The SIM5320 internal GPS also gives accurate results. I tested it with a active antenna and it works fine. 

GPS tracking demo : 
For more details and a closer peek at the board, have a look at this video (Coming soon). 

I will keep you guys posted on the design progress. Stay tuned 🙂

 

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