Elevation motor design and mirror placement
A scanner for a lidar system configured to direct emitted light to scan a field of regard of the lidar system includes a mirror and an actuator assembly. The mirror includes a first end, a second end, and a reflective surface and is pivotable along a mirror axle. The actuator assembly is disposed at the first end of the mirror and includes an asymmetric motor configured to exert a torque on the mirror to cause the mirror to pivot about the mirror axle.
1 . A scanner for a lidar system, the scanner comprising:
a mirror including a first end, a second end, and a reflective surface and being pivotable along a mirror axle, wherein the mirror is configured to direct emitted light of the lidar system; and
an actuator assembly disposed at the first end of the mirror, the actuator assembly including an asymmetric motor configured to exert a torque on the mirror to cause the mirror to pivot about the mirror axle, wherein the asymmetric motor comprises:
a body having a core and a coil; and
a rotor assembly positioned asymmetrically relative to the body, the rotor assembly including a rotor housing and a rotor at least partially disposed within the rotor housing to rotatably couple with the mirror along the mirror axle.
2 . The scanner of claim 1 , wherein the actuator assembly comprises:
the core having a base portion and a plurality of legs extending therefrom, the base portion defining a coil opening;
the coil operably coupled with the core; and
the rotor assembly at least partially disposed between the plurality of legs of the core, the rotor assembly including the rotor housing and the rotor at least partially disposed within the housing to rotatably couple with the mirror along the mirror axle.
3 . The scanner of claim 2 , wherein the rotor assembly includes at least one curved magnet operably disposed on an outer surface of the housing, the at least one curved magnet being positioned between the plurality of legs of the core.
4 . The scanner of claim 1 , wherein the rotor assembly includes at least one bearing disposed within the rotor housing.
5 . The scanner of claim 4 , wherein the at least one bearing includes a needle bearing.
6 . The scanner of claim 1 , wherein the mirror includes a support structure positioned on an opposite side of the reflective surface, the support structure extending a length between the first and second ends of the mirror.
7 . The scanner of claim 6 , wherein the support structure includes a honeycomb support structure.
8 . The scanner of claim 1 , wherein an overall height of the scanner is approximately 2″.
9 . The scanner of claim 1 , wherein the actuator assembly comprises:
the core having a plurality of legs;
the rotor assembly at least partially disposed between the plurality of legs of the core, the rotor assembly including the rotor housing and the rotor at least partially disposed within the housing to rotatably couple with the mirror along the mirror axle.
10 . The scanner of claim 1 , further comprising:
a rotatable polygon mirror having a block including a first wall, a second wall, and a plurality of reflective surfaces extending between the first and second walls, the reflective surfaces being angularly offset from one another along a periphery of the block; and
a polygon mirror axle extending into the block through at least one of the first wall or the second wall, about which the block rotates.
11 . The scanner of claim 10 , wherein the polygon mirror axle is orthogonal to the mirror axle.
12 . The scanner of claim 10 , wherein:
the polygon mirror is configured to receive the emitted light from a light source of the lidar system, and the reflective surfaces of the polygon mirror are configured to sequentially reflect the emitted light toward the reflective surface of the mirror; and
the reflective surface of the mirror is configured to receive the emitted light from the polygon mirror and reflect the emitted light into a field of regard of the lidar system.
13 . The scanner of claim 12 , further comprising a stationary mirror configured to receive the emitted light from the polygon mirror and reflect the emitted light toward the reflective surface of the mirror.
14 . The scanner of claim 1 , wherein the scanner is contained within a housing comprising a window through which the emitted light is transmitted, wherein the mirror is positioned adjacent to the window.
15 . A lidar system comprising:
a light source configured to emit light;
a scanner configured to direct the emitted light to scan a field of regard of the lidar system in accordance with a scan pattern, the scanner including:
a mirror including a first end, a second end, and a reflective surface and being pivotable along a mirror axle; and
an actuator assembly disposed at the first end of the mirror, the actuator assembly including an asymmetric motor configured to exert a torque on the mirror to cause the mirror to pivot about the mirror axle, wherein the asymmetric motor comprises:
a body having a core and a coil; and
a rotor assembly positioned asymmetrically relative to the body, the rotor assembly including a rotor housing and a rotor at least partially disposed within the rotor housing to rotatably couple with the mirror along the mirror axle;
a receiver configured to detect at least a portion of the emitted light scattered by one or more remote targets; and
a controller configured to control motion of at least the mirror to scan the emitted light along the scan pattern.
16 . The lidar system of claim 15 , wherein the actuator assembly comprises:
the core having a base portion and a plurality of legs extending therefrom, the base portion defining a coil opening;
the coil operably coupled with the core; and
the rotor assembly at least partially disposed between the plurality of legs of the core, the rotor assembly including the rotor housing and the rotor at least partially disposed within the housing to rotatably couple with the mirror along the mirror axle.
17 . The lidar system of claim 16 , wherein the rotor assembly includes at least one curved magnet operably disposed on an outer surface of the housing, the at least one curved magnet being positioned between the plurality of legs of the core.
18 . The lidar system of claim 15 , wherein the rotor assembly includes at least one bearing disposed within the rotor housing.
19 . The lidar system of claim 18 , wherein the at least one bearing includes a needle bearing.
20 . The lidar system of claim 15 , wherein the mirror includes a support structure positioned on an opposite side of the reflective surface, the support structure extending a length between the first and second ends of the mirror.