Non-linear springs to unify the dynamic motion of individual elements in a micro-mirror array

1. A device for beam steering in a Light Detection and Ranging (LiDAR) system of an autonomous vehicle, the device comprising:

a first mirror, wherein the first mirror is part of an array of mirrors;

a spring mechanically coupled with the first mirror;

a comb drive configured to move the first mirror, the spring, or both the first mirror and the spring, the comb drive comprising:

a rotor; and

a stator;

a sensor configured to monitor a rotation of the first mirror; and

electronics configured to:

provide a drive signal, wherein the drive signal determines how the rotor is electromagnetically attracted and/or repulsed by the stator;

determine the first mirror is oscillating out of sync with a second mirror of the array of mirrors, based on data from the sensor, wherein:

the first mirror and the second mirror are operable to oscillate in a first steady state and in a second stead state;

the second mirror oscillates in the first steady state; and

the first mirror oscillates in the second steady state; and

alter the drive signal so that a phase difference between the rotation of the first mirror and the drive signal changes, such that the first mirror changes from oscillating in the second steady state to oscillating in the first steady state.

2. The device of claim 1 , wherein the first mirror is formed as part of a microelectromechanical system.

3. The device of claim 1 , wherein the electronics are further configured to verify that the first mirror is operating in sync with the second mirror based on the data from the sensor.

4. The device of claim 1 , further comprising a limiter, wherein the limiter is configured limit a range of motion of the first mirror, the spring, or both the first mirror and the spring.

5. The device of claim 1 , wherein the array of mirrors is configured as a scanning mirror in a LiDAR system.

6. The device of claim 1 , further comprising a plurality of drivers configured to move the plurality of mirrors, wherein the plurality of drivers are configured to drive mirrors of the plurality of mirrors at the same driving frequency.

7. The device of claim 1 , wherein the first mirror is rectangular.

8. A method of using a non-linear system to synchronize motion of a plurality of mirrors, the method comprising:

identifying a first steady state of operation of a mirror-spring system and a second steady state of operation of the mirror-spring system, wherein the mirror-spring system comprises a first mirror that is part of a mirror array and a spring coupled with the first mirror;

determining to use the first steady state based on there being more variance with other mirrors that are part of the array while operating in the second steady state;

identifying an initial phase, or set of initial phases, between a rotation of the first mirror and a first drive signal, wherein:

a first comb drive is used to rotate the mirror-spring system;

the first comb drive comprises a rotor and a stator; and

the first drive signal determines how the rotor is electromagnetically attracted and/or repulsed by the stator; and

starting to rotate the mirror-spring system at the initial phase, or phases of the set of initial phases, will cause the mirror-spring system to operate at the first steady state of operation in relation to the first drive signal;

applying the first drive signal to the first comb drive at the initial phase, or one of the phases from the set of initial phases;

operating the first comb drive so that the mirror-spring system is rotating at the first steady state of operation; and

applying a second drive signal to a second comb drive; and

operating the second comb drive so that a second mirror of the mirror array is rotating at the first steady state of operation in sync with the first mirror.

9. The method of claim 8 , further comprising applying the second drive signal to the second comb drive at one of the phases from the set of initial phases, concurrently with applying the first drive signal to the first comb drive.

10. The method of claim 8 , further comprising:

determining that the first mirror and the second mirror are out of sync;

turning off the first drive signal and the second drive signal based on determining that the first mirror and the second mirror are out of sync;

waiting for the first mirror and the second mirror to return to starting parameters; and

applying the first drive signal to the first comb drive at the initial phase, or one of the phases from the set of initial phases, after waiting.

11. The method of claim 8 , further comprising:

determining that the first mirror is not operating in the first steady state of operation, based on data from a sensor; and

altering the first drive signal, based on determining that the first mirror is not operating in the first steady state of operation, so that a phase difference between the rotation of the first mirror and the first drive signal changes, so that the first mirror will operate in the first steady state.

12. The method of claim 8 , further comprising rotating the first mirror and the second mirror to steer a beam in a LiDAR system.

13. The method of claim 8 , wherein the first mirror is formed as part of a microelectromechanical system.

14. The method of claim 13 , wherein the first mirror is rectangular.

15. The method of claim 8 , wherein:

the first drive signal has a first frequency,

the second drive signal has a second frequency, and

the first frequency is equal to the second frequency.

16. The method of claim 8 , further comprising using a sensor to sense rotation of the first mirror.

17. A method of using a non-linear system to synchronize motion of a plurality of mirrors, the method comprising:

using a first combdrive actuator to move a first mirror at an amplitude and a frequency;

using a second combdrive actuator to move a second mirror at the amplitude and at the frequency of the first mirror so that the first mirror and the second mirror move in a synchronized motion, wherein the motion is non-linear having a first steady state of operation and a second steady state of operation; and

configuring the first mirror and the second mirror to have starting parameters so that the first mirror and the second mirror will both operate at the first steady state of operation.

18. The method of claim 17 , further comprising:

determining that the first mirror and the second mirror are out of sync;

turning off the first combdrive actuator and the second combdrive actuator;

allowing the first mirror and the second mirror to return to starting parameters; and

turning on the first combdrive actuator and the second combdrive actuator so that the first mirror and the second mirror move in the synchronized motion.

19. The method of claim 17 , further comprising rotating the first mirror and the second mirror to steer a beam in a LiDAR system.