Systems and methods for multi-criteria alarming
Systems and methods for using multi-criteria state machines to manage alarming states and pre-alarming states of a hazard detection system are described herein. The multi-criteria state machines can include one or more sensor state machines that can control the alarming states and one or more system state machines that can control the pre-alarming states. Each state machine can transition among any one of its states based on sensor data values, hush events, and transition conditions. The transition conditions can define how a state machine transitions from one state to another. The hazard detection system can use a dual processor arrangement to execute the multi-criteria state machines according to various embodiments. The dual processor arrangement can enable the hazard detection system to manage the alarming and pre-alarming states in a manner that promotes minimal power usage while simultaneously promoting reliability in hazard detection and alarming functionality.
1. A hazard detection system, comprising:
a plurality of sensors comprising a smoke sensor, a carbon monoxide sensor, and a heat sensor;
a radio; and
a state machine operative to:
manage placement of the state machine into a plurality of states of the system, one state at a time, based on sensor values obtained by the plurality of sensors, the plurality of states comprising an alarm state and a pre-alarm state;
transition to the pre-alarm state, wherein when in the pre-alarm state:
the radio is monitored for a hush command; and
if the hush command is received while in the pre-alarm state, transition to a first other one of the plurality of states; and
transition to the alarm state, wherein when in the alarm state:
the radio is monitored for the hush command; and
if the hush command is received while in the alarm state, transition to a second other one of the plurality of states.
2. The hazard detection system of claim 1 , wherein the first other one of the plurality of states is a hushed pre-alarm state, and wherein the second other one of the plurality of states is a hushed alarm state if the sensor values meet a first set of criteria.
3. The hazard detection system of claim 2 , wherein the state machine is operative to:
ignore the hush command while in the alarm state if the sensor values meet a second set of criteria; and
remain in the alarm state.
4. The hazard detection system of claim 2 , wherein when in the hushed alarm state, the state machine is operative to:
revert to the alarm state if the sensor values meet a second set of criteria.
5. The hazard detection system 1 , wherein the plurality of states comprises an idle state and a monitor state, wherein the state machine is operative to:
transition to the idle state, wherein when in the idle state, the plurality of sensors are polled at a first rate;
transition to the monitor state, wherein when in the monitor state, the plurality of sensors are polled at a second rate, wherein the second rate is faster than the first rate.
6. A method for operating a hazard detection system comprising a plurality of sensors, a radio, and a state machine, the method comprising:
managing placement of the state machine into a plurality of states of the system, one state at a time, based on sensor values obtained by the plurality of sensors, the plurality of states comprising an alarm state and a pre-alarm state;
transitioning to the pre-alarm state, wherein when in the pre-alarm state:
monitoring the radio for a hush command; and
if the hush command is received while in the pre-alarm state, transitioning to a first other one of the plurality of states; and
transitioning to the alarm state, wherein when in the alarm state:
monitoring the radio for the hush command; and
if the hush command is received while in the alarm state, transitioning to a second other one of the plurality of states.
7. The method claim 6 , wherein the first other one of the plurality of states is a hushed pre-alarm state, and wherein the second other one of the plurality of states is a hushed alarm state if the sensor values meet a first set of criteria.
8. The method of claim 7 , further comprising:
ignoring the hush command while in the alarm state if the sensor values meet a second set of criteria; and
remaining in the alarm state.
9. The method of claim 7 , wherein when in the hushed alarm state, the method further comprising:
reverting to the alarm state if the sensor values meet a second set of criteria.
10. The hazard detection system 6 , wherein the plurality of states comprises an idle state and a monitor state, the method further comprising:
transitioning to the idle state, wherein when in the idle state, the plurality of sensors are polled at a first rate; and
transitioning to the monitor state, wherein when in the monitor state, the plurality of sensors are polled at a second rate, wherein the second rate is faster than the first rate.
11. The method of claim 6 , wherein the plurality of sensors comprises a smoke sensor, a carbon monoxide sensor, and a heat sensor.