Method and apparatus for self-powered vehicular sensor node using magnetic sensor and radio transceiver
View Patent ↗The invention includes a vehicular sensor node, circuit apparatus and their operations. Power from power source is controlled for delivery to radio transceiver and magnetic sensor, based upon a task trigger and task identifier. The radio transceiver and the magnetic sensor are operated based upon the task identifier, when the task trigger is active. The power source, radio transceiver, magnetic sensor, and circuit apparatus are enclosed in vehicular sensor node, placed upon pavement and operating for at least five years without replacing the power source components. Magnetic sensor preferably uses the magnetic resistive effect to create magnetic sensor state. Radio transceiver preferably implements version of a wireless communications protocol. The circuit apparatus may further include light emitting structure to visibly communicate during installation and/or testing, and second light emitting structure used to visibly communicate with vehicle operators. Making filled shell and vehicular sensor node from circuit apparatus.
1. A circuit apparatus comprising
a vehicle sensor node configured to sense a presence of a vehicle, comprising:
a clock timer configured to maintain a clock count to create a task trigger and a task identifier;
a radio transceiver and a magnetic sensor, both configured to operate based upon said task identifier, when said task trigger is active.
2. The circuit apparatus of claim 1 ,
wherein said magnetic sensor has a primary sensing axis for sensing said presence of said vehicle used to create said magnetic sensor state;
wherein said radio transceiver and said magnetic sensor both configured to operate comprises:
said magnetic sensor responding to said presence of said vehicle to create a sensed vehicle state, when said task identifier indicates a sensor reading;
said radio transceiver sending said vehicle sensed state, when said task identifier indicates a sensor report; and
said radio transceiver receiving a global clock count to confirm-update said clock count, when said task identifier indicates a clock-alignment.
3. The circuit apparatus of claim 2 , wherein said radio transceiver sending, comprises:
said radio transceiver sending said vehicle sensed state to create a received vehicle state at an access point; and
wherein said radio transceiver receiving, comprises:
said radio transceiver receiving said global clock count from said access point.
4. The circuit apparatus of claim 1 ,
wherein said magnetic sensor uses a form of a magnetic resistive effect to create said magnetic sensor state; and
wherein said radio transceiver uses a version of at least one wireless communications protocol.
5. The circuit apparatus of claim 4 ,
wherein said magnetic sensor uses an at least two axis magneto-resistive sensor to create said magnetic sensor state; and
wherein said wireless communications protocol includes an IEEE 802.15 communications standard.
6. The circuit apparatus of claim 5 ,
wherein said magnetic sensor includes a two axis magneto-resistive sensor to create said magnetic sensor state; and
wherein said version of said wireless communications protocol includes an IEEE 802.15.4 communications standard.
7. The circuit apparatus of claim 6 , wherein said radio transceiver uses at least one channel of said version of said at least one wireless communications protocol.
8. The circuit apparatus of claim 7 ,
wherein said magnetic sensor includes a three axis magneto-resistive sensor to create said magnetic sensor state and
wherein said radio transceiver uses a second of said channels of said wireless communications protocol to communicate with a vehicle radio transceiver associated-attached to said vehicle.
9. The circuit apparatus of claim 1 , further comprising:
a computer accessibly coupled with a memory containing a program system;
wherein said clock timer configured, comprises: a clock timer controllably coupled to a said computer to deliver said task trigger and said task identifier, and communicatively coupled with said computer to communicate said clock count;
wherein said radio transceiver and said magnetic sensor, both configured, comprises:
said computer controllably coupled to said radio transceiver and said magnetic sensor; and
program system including the program step of:
operating said radio transceiver and said magnetic sensor based upon said task identifier, when said task trigger is active.
10. The circuit apparatus of claim 9 , wherein the program step of operating comprises the program steps of:
using said magnetic sensor responding to said presence of said vehicle to create a sensed vehicle state, when said task identifier indicates a sensor reading;
sending said vehicle sensed state by said radio transceiver, when said task identifier indicates a sensor report; and
receiving a global clock count from said radio transceiver to confirm-update said clock count, when said task identifier indicates a clock-alignment.
11. The circuit apparatus of claim 1 , further comprising at least one of:
a light emitting structure visibly arranged perpendicular to a primary sensing axis of said magnetic sensor;
a second of said light emitting structures visibly arranged parallel to said primary sensing axis for communicating with a vehicle operator; and
an antenna coupled with said radio transceiver.
12. The circuit apparatus of claim 1 , wherein said radio transceiver and said magnetic sensor both configured to operate, comprises at least one of a finite state machine, a field programmable logic device, and a computer.
13. The circuit apparatus of claim 1 , wherein said clock timer configured to maintain comprises means for maintaining said clock count to create said task trigger and said task identifier.
14. The circuit apparatus of claim 1 , wherein said radio transceiver and said magnetic sensor, both configured to operate further comprises means for operating said radio transceiver and said magnetic sensor based upon said task identifier, when said task trigger is active.
15. The circuit apparatus of claim 13 , wherein said radio transceiver and said magnetic sensor, both configured to operate further comprises means for operating said radio transceiver and said magnetic sensor based upon said task identifier, when said task trigger is active.
16. The circuit apparatus of claim 15 , wherein at least one of said means for maintaining and said means for operating, comprises at least one of a finite state machine, a field programmable logic device, and a computer.
17. The circuit apparatus of claim 1 , wherein said clock timer configured to maintain, comprises at least one of a finite state machine, a field programmable logic device, and a computer.
18. A vehicular sensor node for sensing a presence of a vehicle, comprising:
a radio transceiver;
a magnetic sensor;
a computer coupled with a clock timer to maintain
a clock count to create a task trigger and a task identifier; and
said computer coupled to a radio transceiver and a magnetic sensor to operate
said radio transceiver and said magnetic sensor based upon said task trigger and said task identifier.
19. The vehicular sensor node of claim 18 , further comprising a shell enclosing said radio transceiver, said magnetic sensor, said computer and said clock timer.
20. The vehicular sensor node of claim 18 , further comprising said radio transceiver coupled to an antenna.