Let us lay the foundation first. The expectation with any headless (device without a screen/button for feedback, relying on machine I/O/codes for troubleshooting) hardware is simple: It should just work, reliably and without manual intervention (assuming proper configuration, installation and maintenance). Once that is met, I personally couldn’t care less where it is designed, manufactured, assembled or divined.
These post(s) will serve to detail lessons learnt as we set about integrating hardware GPS devices and conduct numerous rounds of experiments with multiple vendors, products and firmware variations to identify one that matched our requirement (without explicitly recommending any one brand).
For electronic hardware, there are 3 factors: power, power and power. This can’t be stressed enough. If the power supply provided is not stabilized to the device, you’ll be seeing unexplained system crashes, device hangups and worst case bad data (though this is very rare).
- Make sure you’ve checked the output voltage from the ‘running’ vehicle and confirmed that the DC output is steady.
- The supplied voltage should ideally be midway in the supported range of the device. Never operate at the extreme end of the devices’ tolerance, you’ll likely be pushing some component to the limit and increasing the chances of an early failure. For instance if your device works from 8 – 24V, run at 12-16V not at 24V itself.
When you’re sending data continuously, every packet counts! So make them count!
- Avoid overheads associated with data expensive protocols like HTTP. Preferably use binary TCP or UDP if your device supports it. This could be an important factor in your selection of a device if your software stack can support it.
Network is everything:
- Make sure that your GSM provider has adequate signal strength in the area that you are planning to cover. Engage multiple cellular operators and work the best deal in terms of network, availability and features they’re offering. If you can find a CDMA device coupled with a good network in your area, take advantage of it by selecting a device which works with CDMA networks (keep in mind the frequencies and protocol variations involved)
Coming up: Data storage, Battery Backup, External Antenna and other factors