FIELD OF THE INVENTION 0001 The present invention is related to steering and scanning mechanisms. More specifically, the present invention is related to a scanning mechanism having an unobstructed view, operates continuously in one direction and can operate in any orientation.

BACKGROUND OF THE INVENTION 0002 The ability to measure surfaces and objects in 3-D is becoming increasingly important for many fields such as autonomous vehicle navigation and obstacle detection, quarry mapping, landfill surveying, and hazardous environment surveying. The current state of the art for scanning mechanisms is unable to meet the demand of many of these applications. Typical scanners are slow, unable to measure with an unobstructed view and inflexible in their ability to use different types of range sensors. The present invention overcomes these limitations and provides a system that will meet the existing demand for more advanced scanning mechanisms.

SUMMARY OF THE INVENTION 0003 The present invention pertains to a directing apparatus. The directing apparatus comprises a mechanism for producing steerable energy. The directing apparatus also comprises a mechanism for steering energy from the producing mechanism. The steering mechanism is in communication with the producing mechanism. 0004 The present invention pertains to a directing apparatus. The directing apparatus comprises a mechanism for producing steerable energy. The directing apparatus also comprises a mechanism for scanning steerable energy from the producing mechanism. The scanning mechanism is in communication with the producing mechanism and operable in any orientation. 0005 The present invention pertains to a directing apparatus. The directing apparatus comprises a mechanism for producing steerable energy. The directing apparatus also comprises a mechanism for scanning steerable energy from the producing mechanism. The scanning mechanism is in communication with the producing mechanism and performing a line scan at a given adjustable angle. 0006 The present invention pertains to a directing apparatus. The directing apparatus comprises a mechanism for producing steerable energy. The directing apparatus also comprises a mechanism for scanning steerable energy from the producing mechanism. The scanning mechanism is in communication with the producing mechanism and able to be stopped at a first location and at least a second location so the energy can be secured in a constant direction at each location for as long as desired. 0007 The present invention pertains to a directing apparatus. The directing apparatus comprises a mechanism for producing steerable energy. The directing apparatus also comprises a mechanism for scanning steerable energy from the producing mechanism. The scanning mechanism is in communication with the producing mechanism and rotatable 360 degrees without any obstructions from the apparatus itself to the steerable energy that is used to scan the surrounding. 0008 The present invention pertains to a directing apparatus. The directing apparatus comprises a mechanism for producing steerable energy. The directing apparatus also comprises a mechanism for scanning steerable energy from the producing mechanism. The scanning mechanism is in communication with the producing mechanism and having an adjustable nod angle between a first predetermined angle and a second predetermined angle. 0009 The present invention pertains to a directing method. The directing method comprises the steps of producing steerable energy. Next there is the step of scanning a surrounding continuously in a first direction with the steerable energy.

BRIEF DESCRIPTION OF THE DRAWINGS 0010 In the accompanying drawings, the preferred embodiment of the invention and preferred methods of practicing the invention are illustrated in which: 0011 FIG. 1 is a functional block diagram showing the major device components and their interactions of the present invention. 0012 FIG. 2 is a system process flow diagram showing the invention according to its first embodiment. 0013 FIG. 3 is a second level system process flow diagram showing the invention according to its first embodiment. 0014 FIG. 4 is an isometric view of the mechanism showing the direction of rotation and translations of the components in the invention according to its first embodiment. 0015 FIG. 5 is a schematic representation of a cam mechanism. 0016 FIG. 6 is a schematic representation of a side cut-away view of the speed differential ring mechanism. 0017 FIG. 7 is a schematic representation of a yoke assembly. 0018 FIG. 8 is a schematic representation of a mirror assembly. 0019 FIG. 9 is a graph associated with the movement of the mirror assembly during operation of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT 0020 Referring now to the drawings wherein like reference numerals refer to similar or identical parts throughout the several views, and more specifically to FIG. 4 thereof, there is shown a directing apparatus 10. The directing apparatus 10 comprises a mechanism 12 for producing steerable energy. The directing apparatus 10 also comprises a mechanism for steering energy from the producing mechanism 12. The steering mechanism 14 is in communication with the producing mechanism 12. 0021 The mechanism for producing steerable energy preferably includes a mechanism 16 for producing electromagnetic radiation. The electromagnetic radiation producing mechanism 16 preferably includes a mechanism 18 for producing laser energy. 0022 The steering mechanism 14 preferably includes a scanning mechanism 20 which continuously scans a surrounding in a first direction. Preferably the scanning mechanism 20 continually scans in the first direction at a speed which is adjustable. Preferably the scanning mechanism 20 continually scans in the first direction at a speed which is adjustable between 10-4000 rpm. The scanning mechanism 20 preferably includes a sensor mechanism 58 which receives electromagnetic radiation, such as the laser energy, back from the surrounding and determines how the surrounding looks from the energy. 0023 The scanning mechanism 20 preferably includes a guide mechanism 22 which guides the radiation. The guide mechanism 22 preferably has a nod rate which is adjustable. The guide mechanism 22 preferably has a nod rate which is adjustable from 0.01-8 Hz. 0024 The scanning mechanism 20 preferably includes a yoke assembly 24 which holds the guide mechanism 22. Preferably the scanning mechanism 20 includes a spindle assembly 26 upon which the yoke assembly 24 is mounted and which rotates continuously in the first direction. The scanning mechanism 20 preferably includes a controller 28 which regulates the spindle assembly 26. Additionally, the scanning mechanism 20 preferably includes an encoder mechanism 30 which measures the angular position of the spindle assembly 26. Preferably the scanning mechanism 20 includes a cam mechanism 32 connected to the guide mechanism 22 and the spindle mechanism which moves the guide mechanism 22 in a second direction perpendicular to the first direction. 0025 The guide mechanism 22 preferably includes a mirror assembly 36, as shown in FIG. 8. The yoke assembly 24 preferably includes a yoke 34 having a top 40 and a bottom 42 and an optical bore 38 for the electromagnetic radiation, such as the laser energy, to travel through the yoke 34, as shown in FIG. 7. The optical bore 38 is in alignment with the mirror assembly 36. Furthermore, the mirror assembly 36 preferably includes an axle 44 which connects the mirror assembly 36 to the yoke 34 and which is housed at the top 40 of the yoke 34. The laser energy producing mechanism 18 is preferably disposed at the bottom 42 of the yoke 34 and in alignment with the optical bore 38 so laser energy from the laser energy producing mechanism 18 can transmit along the optical bore 38 and be reflected by the mirror assembly 36. 0026 The scanning mechanism 20 preferably includes a speed differential ring mechanism 46 bearinged coaxially with the yoke 34 and which rotates. The cam mechanism 32 moves along the speed differential ring mechanism 46 which causes the mirror assembly 36 to rotate in the second direction as a function of the relative difference in rotational speed between the speed differential ring mechanism 46 and the spindle assembly 26. Preferably the speed differential ring mechanism 46 has a vertical surface having a shape of a triangular wave pattern. 0027 The cam mechanism 32, as shown in FIG. 5, is preferably comprised of a cam follower wheel 50 which moves along and tracks the vertical surface of the speed differential ring mechanism 46. The cam mechanism 32 is also comprised of the toothed rack 48 which is attached to the cam follower wheel 50. The cam mechanism 32 is comprised of a linear bearing 54 which houses the toothed rack 48. Preferably the guide mechanism 22 includes a spur gear 52 mounted coaxially on each end of the axle 44. The spur gear 52 meshes with the toothed rack 48 which actuates the axle 44 to move the mirror assembly 36 in the second direction as a function also of the gear tooth ratio between the toothed rack 48 and the spur gear 52. The cam mechanism 32 preferably also comprises a spring mechanism 56 disposed between and connected with the cam wheel 50 follower and the toothed rack 48 which allows the mirror assembly 36 to reduce backlash of the mirror assembly 36 and maintain the mirror assembly 36 in a stable configuration during rotation. The mirror assembly 36 preferably has a weight distribution which is loaded to tip it backwards to keep the cam wheel 50 follower on the speed differential ring mechanism 46 as the mirror assembly 36 rotates by centrifugal force which is a function of the rotational speed of the mirror assembly 36. 0028 The present invention pertains to a directing apparatus 10. The directing apparatus 10 comprises a mechanism for producing steerable energy. The directing apparatus 10 also comprises a mechanism for scanning steerable energy from the producing mechanism 12. The scanning mechanism 20 is in communication with is the producing mechanism 12 and operable in any orientation. 0029 The present invention pertains to a directing apparatus 10. The directing apparatus 10 comprises a mechanism for producing steerable energy. The directing apparatus 10 also comprises a mechanism for scanning steerable energy from the producing mechanism 12. The scanning mechanism 20 is in communication with the producing mechanism 12 and performs a line scan at a given adjustable angle. The line scan can be accomplished, for instance, by having the motor mechanism move the mirror mechanism to a desired location, or using windowing techniques, as is well known in the art. 0030 The present invention pertains to a directing apparatus 10. The directing apparatus 10 comprises a mechanism for producing steerable energy. The directing apparatus 10 also comprises a mechanism for scanning steerable energy from the producing mechanism 12. The scanning mechanism 20 is in communication with the producing mechanism 12 and able to be stopped at a first location and at least a second location so the energy can be secured in a constant direction at each location for as long as desired. This can be accomplished, for instance, by controlling the motor mechanism so the mirror mechanism is held at the desired locations. 0031 The present invention pertains to a directing apparatus 10. The directing apparatus 10 comprises a mechanism for producing steerable energy. The directing apparatus 10 also comprises a mechanism for scanning steerable energy from the producing mechanism 12. The scanning mechanism 20 is in communication with the producing mechanism 12 and rotatable 360 degrees without any obstructions from the apparatus itself to the steerable energy that is used to scan the surrounding. 0032 The present invention pertains to a directing apparatus 10. The directing apparatus 10 comprises a mechanism for producing steerable energy. The directing apparatus 10 also comprises a mechanism 14 for scanning steerable energy from the producing mechanism 12. The scanning mechanism 20 is in communication with the producing mechanism 12 and having an adjustable nod angle between a first predetermined angle and a second predetermined angle. 0033 The present invention pertains to a directing method. The directing method comprises the steps of producing steerable energy. Next there is the step of scanning a surrounding continuously in a first direction with the steerable energy. 0034 Preferably, the scanning step includes the step of rotating a guide mechanism 22 from a mirror assembly 36 continuously in the first direction. Next there is the step of reflecting the energy into the surrounding with the mirror assembly 36 as the mirror assembly 36 rotates. Then there is the step of receiving the energy back at the mirror assembly 36 from the surrounding. Then there is the step of reflecting the energy with the mirror assembly 36 to a sensor mechanism 58. Next there is the step of determining how the surrounding looks from the energy received at the sensor mechanism 58. 0035 The rotating step preferably includes the steps of rotating a spindle assembly 26 in the first direction upon which a yoke assembly 24 that holds the mirror assembly 36 is mounted. Then there is the step of rotating a speed differential mechanism bearing coaxially with the yoke assembly 24 and along which a cam mechanism 32 connected to the guide mechanism 22 moves to cause the mirror assembly 36 to rotate in a second direction as a function of the relative difference in rotational speed between the speed differential ring mechanism 46 and the spindle assembly 26. 0036 In the operation of the preferred embodiment, there is shown in FIGS. 4, 5, 6, 7 and 8, a two-dimensional scanning mechanism 20 which is used to steer energy from lasers of a laser producing mechanism 18 to range detection sensors of a sensor mechanism 58 in order to generate range data from the entire surroundings of the scanning mechanism 20. The scanning mechanism 20 is comprised of a guide mechanism 22 having a gold coated aluminum mirror of mirror assembly 36, a yoke assembly 24 which allows the mirror assembly 36 to pivot vertically, a spindle assembly 26 which rotates the yoke assembly 24 horizontally, a speed differential ring mechanism 36 which generates the vertical scan motion, two brushless DC motors 60, two incremental encoders of an encoder mechanism 30, two optical switches 62, electronic circuits to control the motor velocities, electronic circuits to establish the position of the mirror assembly 36 in space, electronic circuits to collect and store range data, a mechanical housing used to mount a range detection sensor of sensor mechanism 58, and a commercially available range detection device, currently a Riegl laser spot sensor and an Amplitude Modulated Continuous Wave (AMCW) laser range finder from Z&F Inc. of sensor mechanism 58. Essentially, any laser range finder which produces energy which fits through the optical bore can be used. 0037 The Riegl laser spot sensor uses a laser diode and a set of lenses to generate a collimated pulse of infrared laser energy. This beam of energy travels away from the sensor until it comes in contact with a surface or object. The energy reflects off of the object and a receiver in the sensor detects the reflected energy. By measuring the time elapsed between the beginning of the pulse and the return of the reflected energy to the receiver, the distance to the object can be calculated by using the speed of light as a constant. 0038 The Z&F AMCW laser sensor modulates the amplitude of a two continuous beams of laser light generated by two laser diodes. There are two diodes used to improve the performance of the system over the large range of operation. The receiver in the sensor detects the light reflected from the environment and calculates the time of flight by matching the return wave form to the output modulation. This is then used to calculate the distance to the object. 0039 In order to generate range from many discrete points in a volume surrounding the sensor, the laser energy must be steered to each point in the volume of interest. 0040 A gold plated aluminum mirror is used to direct the energy pulse/beam. The laser reflects off of the mirror surface at the same angle it hits the mirror. Even though the mirror assembly 36 having the mirror is continuously moving, the reflected light is still received by the mirror due to the fact that the laser energy travels at the speed of light. This makes the change in mirror position negligible and allows the sensor's receiver to collect the reflected energy. The limit on a range finders speed is generally derived by processing time as apposed to time of flight of the laser energy. 0041 The mirror is attached to an axle 44 which is then housed in a yoke 34 on bearings so that the mirror can rotate in the vertical axis. The mirror assembly 36 includes precisely machined counterweights 64 to dynamically balance the mirror vertical axis. 0042 The yoke 34 is connected to a bearinged spindle assembly 26 which rotates in the horizontal axis. The spindle assembly 26 contains a spindle pulley which is connected to a brushless DC spindle motor 60 with a belt. 0043 The spindle motor 60 speed is regulated using a commercially available motor control electronic circuit which implements a feedback loop using a hall-effect sensor mounted internally to the motor. 0044 An incremental encoder of the encoder mechanism 30 is attached to the spindle motor 60 to measure the angular position of the spindle assembly 26 with respect to an index point. The index point is determined by using an optical switch 62 as is well known in the art. The absolute azithumis angle of the scanning mechanism 20 is determined by the following equation: 1

y p h = N y x S y - o f f s e t

S y = \frac{360}{1000 4 G R y}

0045 Where: 0046 Thetayphazimuth of the Yoke 0047 NyYoke encoder reading in counts 0048 Sydegrees/count 0049 GRyGear Ratio on Yoke 0050 OffsetOffset of optical switch 0051 The mirror axle 44 is actuated by a spur gear 52 mounted coaxially on the axle 44. The spur gear 52 meshes with a toothed rack 48 which is housed in a linear bearing 54 attached to the spindle assembly 26. The lower end of the rack 48 is attached to a cam follower wheel 50 which runs along the edge of the speed differential ring mechanism 46. 0052 The speed differential ring mechanism 46 is bearinged coaxially with the Yoke 34 and is driven by the speed differential pulley which is connected to a brushless DC motor 60 with a timing belt. The speed differential ring mechanism 46 has a vertical surface which has been machined in a triangular wave pattern. As the ring mechanism 46 rotates, the cam follower wheel 50 tracks the shape of the triangular wave which pushes the rack 48 up and down and drives the spur gear 52 which rotates the mirror in the vertical axis. 0053 The rack bearing assembly is attached to the spindle assembly housing so that the rate of the vertical mirror rotation is a function of the relative difference in rotational speed between the speed differential ring mechanism 46 and the spindle assembly 26. 2

NodRate = 4 (YokeRPM - SdrRPM) (\frac{1}{60})

0054 The amount of vertical travel of the mirror is a function of the gear tooth ratio between the rack 48 and the spur gear 52, and as a function of the amplitude of the triangular wave pattern machined on the speed differential ring mechanism 46. 3

A lp h a Me c h a n i c a l = \frac{(57.296 Z s)}{R g}

0055 Where: 0056 AlphaMechanicalthe change in the mechanical angle of the mirror axle 0057 ZsThe change in position of the rack 0058 RgThe radius of the Spur Gear 0059 The vertical angular position of the mirror is determined by calculating the angular position of the cam follower wheel on the speed differential ring. This is accomplished by using an incremental encoder on the speed differential motor and an optical switch mounted in the scanner ground housing which is activated by a switch pin 72 inserted in the side of the speed differential ring mechanism 46. 0060 With reference to FIG. 9, 4

S s = \frac{360}{1000 4 G R s}

s p h = N s S s

c s = y p h - s p h

0061 Where: 0062 GRsGear Ratio on SDR 0063 NsSDR encoder reading in counts 0064 SsDegrees/Count 0065 ThetasphAzimuth of SDR 0066 ThetacsRelative Position of SDR to Yoke 0067 If: 5

c s > \frac{}{2} s = c s -

c s < \frac{}{2} s = c s +

Z s = A m p l i t u d e - \frac{4}{} fabs (s)

0068 Where: 0069 ZsThe change in rack position 0070 An electronic circuit is used to allow a user of the scanning mechanism 20 to specify the horizontal and vertical scan speeds, as is well known in the art. The speed control circuit regulates the speed of each motor 60 and monitors the difference in the speeds so that the resulting scanning motions are very accurate. 0071 A second version of the scanning mechanism 20 uses a single brushless DC motor with two output pulleys to actuate both the spindle assembly 26 and the speed differential ring mechanism 46. This version relies on the gear ratio between the output pulleys to set the vertical scan speed. This version of the scanning mechanism 20 requires less control circuitry and one less motor but does not allow a user to have as much flexibility with speed controls. 0072 A one motor version can be used to create a scanner that has a fixed scan pattern at a given rpm. This is done by belting both the yoke 34 and the speed differential ring mechanism 46 to the same drive motor with different gear ratios. 0073 The scanning mechanism 20 must be balanced in order to allow for proper operation. Specifically, the mirror assembly 36 is balanced so that the center of mass is located at the center of the mirror substrate on the mirror surface. The mirror assembly 36 is also balanced with respect to inertia. As the mirror position changes, the inertia of the scanning mechanism 20 remains constant. This allows the scanning mechanism 20 to be under a constant load even though the system is changing dynamically. 0074 The mirror is also loaded slightly to tip it backwards to keep the cam follower wheel 50 on the speed differential ring mechanism 46. This loading increases as the revolution speed is increased. This enables the scanning mechanism 20 to operate in any orientation and even in environments that have high levels of vibration. The mirror assembly 36 is loaded in two ways. The first is by providing a spring mechanism 56 on the cam mechanism 32. This takes out any backlash in the scanning mechanism 20 and provides a preloading force on the mirror assembly 36. The second way is by moving the center of mass of the mirror assembly 36 to the back by 0.0025. This makes the lower part of the mirror want to hang below the center the mirror axle 44. The force is also a function of scanning speed based on the centrifugal force generated during rotation. Autocad 3-D models are used to balance the scanning mechanism 20. The process is straightforward to one skilled in the art. First all of the components are modeled and assembled. The density of each component is then entered into the system and autocad calculates the center of the mass and inertias. The designer then adjusts the components dimensions and locations to receive the desired balanced and inertia results. The force of the spring mechanism 56 is the main factor that allows the scanning mechanism 20 to operate upside down. However, the loading of the mirror assembly 36 backwards is caused not so much by gravity but by the centrifugal force generated by the motion of the scanning mechanism 20. Therefore, the mirror assembly 36 tries to rotate in the direction that will load the mirror assembly 36 when it spins regardless of orientation. This explains why the scanning mechanism 20 can also operate upside down without a spring mechanism 56 in the scanning mechanism 20. 0075 FIG. 1 is a schematic of the physical components and their connection with each other in the scanning mechanism 20. The scanning mechanism 20 contains the energy device and scanning head. There are the laser or energy producing devices' electronics 2, which are well known in the art. There is a digital input/output device 3 for interfacing with the electronics, which is well known in the art. There is an encoder card 4 which allows the encoders to be read which determines the scanning mechanism position. The motor controller 5 regulates the drive mechanism's velocity, position and acceleration based on commands from the CPU, which is well known in the art. The CPU 6 is the main processor of the scanning mechanism 20. The communication controller 7 can be anything from a serial port to a SCSI-2 port or any device for communicating between the device and the host machine. The host machine 8 is where the user enters all commands and views the data. 0076 FIG. 2 is a diagram that lays out the general flow diagram of the current user software. FIG. 3 is the detailed control software flow chart, and FIG. 2 is one level higher since it is at the user level. 0077 FIG. 3 is a flow chart showing the interactions of the different software control modules. This demonstrates one possible implementation method for controlling the scanning mechanism 20 and calculating the 3-D data from the raw position feedback signals. 0078 There are three main control levels of the apparatus 10: high level control, motor control, and data control. The high level 20 control handles all of the user interface commands, timing (laser firing), and high level control of the motor and data control modules. The high level control is used for setting up the scanning mechanism 20 based on user inputs, downloading the required motor speeds to the motor control module and setting the fire rate to get the desired data rate. The motor control module is an off the shelf motor controller that regulates the motors acceleration and velocity with respect to the speeds requested by the high level control. The data control module calculates the spherical coordinates based on the scanner physical position and combines this data with the range and amplitude value return by the distance measurement system. All of this data is then passed into a FIFO (First In First Out) where it is sent back to the host machine. The circles are software modules that perform the tasks stated with the circle. The arrows are data paths within the control software of the scanning mechanism. For example, Motor Setpoint Generator; this module simply sets the motor setpoints for velocity, acceleration and position based on the output of the Motor Supervisory control module and sends its information to the motor controllers. 0079 A description of the components of the scanning mechanism 20 now follows: 0080 32. Cam Mechanism (FIG. 5) 0081 50. Cam Follower WheelAllows smooth motion of mechanism along the top of the SDR. The wheel follows the curve on the top of the SDR. 0082 56. Spring MechanismThe spring preloads the mechanism to reduce backlash and the dynamics effects of spinning at high rpm's. 0083 48. Linear Toothed RackThe rack gear meshes with the spur gear on the mirror axle to turn linear motion into rotary motion. 0084 54. Linear BearingThe bearing surface for the rack gear. 0085 66. Cam MountThe mount assembly provides mounting of the cam mechanism components to the Yoke. 0086 46. Speed Differential Ring (SDR) MechanismThe SDR provides mounting for the assembly components and the curve that provides the motion for the cam mechanism. (FIG. 6) 0087 68. SDR PulleyProvides pulley surface for SDR to connect to the drive motor with a timing belt. 0088 70. Bearing SurfacesMounting location for the high speed bearings that mount to the Yoke assembly. 0089 72. Pin MountsLocation of the mechanical pins that activate the optical switches. 0090 62. Optical SwitchDetects pins to determine position of scanning mechanism. 0091 76. Exterior BearingsExterior high speed bearings that connect the scanning assembly to housing ground. 0092 78. Mounting for scanning assembly to the housing ground. 0093 24. Yoke Assembly (FIG. 7) 0094 34. Yokeprovides mounting for assembly components and optical bore for energy to travel through mechanism to mirror. 0095 80. BearingsYoke high speed bearings that connect assembly to the SDR. 0096 82. Mounting location for the mirror assembly. 0097 84. Yoke PulleyProvides pulley surface for Yoke to connect to the drive motor with a timing belt. 0098 36. Mirror Assembly (FIG. 8) 0099 64. Counter WeightsProvide balancing of the assembly mass and inertias. 0100 52. Spur gearThe spur gear meshed with the linear rack of the cam mechanism and turns the linear motion of the cam into rotational movement. 0101 44. Mirror AxleProvides the mounting for the assembly parts and provides alignment for mirror substrate. 0102 86. Mirror SubstrateThe aluminum substrate has a gold covered face to provide the mirror surface to reflect the energy beam. 0103 88. Yoke CounterweightProvides balancing for the cam mechanism mass. 0104 Although the invention has been described in detail in the foregoing embodiments for the purpose of illustration, it is to be understood that such detail is solely for that purpose and that variations can be made therein by those skilled in the art without departing from the spirit and scope of the invention except as it may be described by the following claims.