Just one of the most practical factors about having cats is their independent lifestyle: most are content to love them selves outside all day, only coming back property when it’s time for evening meal and a nap. What your cat will get up to for the duration of the working day stays a thriller, unless you in shape it with a GPS collar. When [Sahas Chitlange] went looking for a GPS tracker for his beloved Pumpkin, he identified that none were being particularly to his liking: far too slow, as well huge, or merely unreliable. This led him to style and develop his individual, known as Find My Cat.
The heart of the device is an A9G GSM/GPS board, based on the RDA8955 system-on-chip. [Sahas] merged this with a knowledge SIM card, a 2600 mAh lithium battery and a charger module to make a fully self-contained GPS tracker capable of transmitting place data in actual time. The method is housed in a hand-manufactured brass box made to be attached to a cat harness, where by it sits securely on Pumpkin’s back.
It took a little bit of experimentation to come across a workable antenna setup for this program, because the brass box works as a Faraday cage. [Sahas] as a result made the lid of the enclosure out of wooden, and embedded two slim strips of brass inside it to make a dipole antenna. Checks in his car verified that it acquired a responsible resolve and was ready to connect as a result of the GSM network.
On the software package facet, The A9G module arrived with a C/C++ based mostly SDK that [Sahas] discovered so inconvenient to use that he made a decision to replace the complete point with a MicroPython set up. He then programmed it with a uncomplicated schedule that waits for an MQTT concept to commence tracking, and in any other case stays in rest mode. Spot knowledge is sent to a Raspberry Pi functioning Traccar, an open up-supply GPS monitoring server that supplies a all set-to-use web interface. Getting Pumpkin’s locale is now as basic as opening a internet browser, navigating to the Pi’s IP tackle and wanting at the map.
As in a lot of wearables, the largest portion of the method is the battery, which in this situation delivers a very good twelve times of usage amongst recharge classes. We’d assume that to be loads, unless Pumpkin is one of those cats that like to go on multi-week expeditions. Constrained battery lifestyle is a popular dilemma for GPS pet trackers probably switching to an extremely-very low-ability LoRa-centered technique may assistance.