Updated: Feb 21
The short answer is very.
Safety, without fail, has been our number one priority when designing the LitterPod™. Our philosophy is if it's good enough for Kuba and Leia to use, it's good enough for fellow cat lovers cats to use too.
The LitterPod™ has three forms of cat 'detection'. The sensors that detect the presence of your cat are:
Weight Sensors - The load cells on each of the four legs allows for the weight to be continuously monitored. This is triggered when the measured weight exceeds 500g, a detection level significantly less than the even the lightest of kittens!
Motion Sensor - A highly sensitive infra-red / proximity sensor is housed within the top of the door entrance. This reliably detects the presence of a nearby object without any physical contact and can help distinguish when your cat is entering or leaving the Litterpod.
Lid Sensor - A hall effect sensor is built into the lid and can detect whether the lid is attached or not. In the case that it is removed, the lockdown feature kicks in, meaning operation can only occur in manual mode.
Another safety feature is the Litterpod's ability to detect when there is too much strain on the rake. If excess weight is applied to the rake (in either direction), the motor switches off and the Litterpod™ will enter a fault state.
This can be recovered by pressing the home button but will continue to trigger if the strain on the rake remains. While we don't envision this ever being something you'll encounter we we've built it in as an extra fail-safe. This video shows how this works. Please note in order to film this video we have had to disable the Active IR sensor!
Along with the sensors above, there are a number of physical micro-switches built into the mechanics of the LitterPod™. Because these are mechanical switches they're extremely reliable and have the role of detecting various conditions such as when the bin lid or waste compartment is open or closed. They also monitor the location of the rake during its cycle.
An important example of how this works is the bin lid automatically opens as the rake approaches it, but if the micro switch does not trigger, the system will detect this and put the LitterPod™ into lockdown. This might happen if something gets left on the waste compartment preventing it from opening properly as an example.
The software has been programmed so that the LitterPod is in a perpetual state of self-diagnosis. It consistently checks the sensors are working and that the micro-switches are being activated in the correct sequence during cleaning cycles. If a problem is detected the LitterPod's LED's will flash red signalling there's a problem and shut down. Unplugging from the mains will hard reset the LitterPod should it be required.
Our view has always been that we'd rather the LitterPod™ stopped working altogether than pose any risk to our furry friends and their human families.
We've been careful to not cut any corners with the electronics, software and firmware. We have been working closely with our colleagues at XED based in Bristol, UK who have spent the last year working specifically on the LitterPod™.
If you have any questions on this, please contact us any time at firstname.lastname@example.org.