CA2111117C - Spatial measurement recovery system - Google Patents
Spatial measurement recovery systemInfo
- Publication number
- CA2111117C CA2111117C CA002111117A CA2111117A CA2111117C CA 2111117 C CA2111117 C CA 2111117C CA 002111117 A CA002111117 A CA 002111117A CA 2111117 A CA2111117 A CA 2111117A CA 2111117 C CA2111117 C CA 2111117C
- Authority
- CA
- Canada
- Prior art keywords
- data
- environment
- shape
- gathering
- sensor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
- G01S17/88—Lidar systems specially adapted for specific applications
- G01S17/89—Lidar systems specially adapted for specific applications for mapping or imaging
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C15/00—Surveying instruments or accessories not provided for in groups G01C1/00 - G01C13/00
- G01C15/002—Active optical surveying means
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
- G01S7/481—Constructional features, e.g. arrangements of optical elements
- G01S7/4811—Constructional features, e.g. arrangements of optical elements common to transmitter and receiver
- G01S7/4813—Housing arrangements
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S367/00—Communications, electrical: acoustic wave systems and devices
- Y10S367/907—Coordinate determination
Abstract
A spatial measurement recovery system and method which determines the position, orientation, shape and/or operational characteristics of an environment (300). The system includes a data gathering apparatus (100) and a model building apparatus (200). The data gathered may then be transformed into a CADD model or an as-built or as-is environment, or to otherwise map the environment in three dimensions.
Description
~92/22832 ~ Y PCT/VS92~0~132 ~P~TIAL ~BA~R~~N$ RECOV~Y ~Y~T~
FIELD OF THE INVENTION
The present invention relates to a spatial measurement recovery system which determines and xecords the positional, dimensional and/or operational information regarding an object and/or an en~ironment.
BACKGROUND OF THE INVENTION
lOComputer Aided Design and Drafting (CADD) ha~ b~come a stand2rd design ~ool for manipulating and recording design information in many industries, including the manufacturing and construction industries, In this way, design information, such as for a manufactured product or a construction project, is transformed into a computerized model. CA~D models are accurate depictions of the position, shape and orientation of the objects composing the design ! and their relationship to each other and the environment . in which they are contained.
: : Beliveau et al, U. S. Patent Application Serial No. 07/570,26~, filed August 1?, l~go, and Dornbusch et al, U. S. Patent ; Appli:cation No. 0~/636,459, filed December 31, l990, the contents of which are incorporated herein by reference, describes a system and method in which a CADD model is used in conjunction with a portable posl~ion~sensor:and a plurality of reference stations to position dis~inguished points in an enYironment. In the system and method~: disclosed ~by ~Beliveau ~t al., actual position and orientation informatiQn of a vehicle, for example, can be transmitted back ;to the ~computer and compared to the desired :posltion~o~ the~vehicle in thè CADD model, and the~ the pos~tion 30~ of~the vehicle oan~be automatically corrected if necessary.
Unfor~unately,~a :fi~ished environment often differs from its esi;gn, due to problems such as errors in design and tolerance :capa~ility. Thus, there is a difficulty that the CADD model no , longer accur~tely represents the environment constructed therefrom.
~:CADD~models could be used to record the "as-built" or 9'as-is"
position, shape:~and orientation data of the components of an environment, for example, an existing manufactured product or indust~ial ~acility, if these data could be determined.
;
$UBS~ I l'UTE SHEET
FIELD OF THE INVENTION
The present invention relates to a spatial measurement recovery system which determines and xecords the positional, dimensional and/or operational information regarding an object and/or an en~ironment.
BACKGROUND OF THE INVENTION
lOComputer Aided Design and Drafting (CADD) ha~ b~come a stand2rd design ~ool for manipulating and recording design information in many industries, including the manufacturing and construction industries, In this way, design information, such as for a manufactured product or a construction project, is transformed into a computerized model. CA~D models are accurate depictions of the position, shape and orientation of the objects composing the design ! and their relationship to each other and the environment . in which they are contained.
: : Beliveau et al, U. S. Patent Application Serial No. 07/570,26~, filed August 1?, l~go, and Dornbusch et al, U. S. Patent ; Appli:cation No. 0~/636,459, filed December 31, l990, the contents of which are incorporated herein by reference, describes a system and method in which a CADD model is used in conjunction with a portable posl~ion~sensor:and a plurality of reference stations to position dis~inguished points in an enYironment. In the system and method~: disclosed ~by ~Beliveau ~t al., actual position and orientation informatiQn of a vehicle, for example, can be transmitted back ;to the ~computer and compared to the desired :posltion~o~ the~vehicle in thè CADD model, and the~ the pos~tion 30~ of~the vehicle oan~be automatically corrected if necessary.
Unfor~unately,~a :fi~ished environment often differs from its esi;gn, due to problems such as errors in design and tolerance :capa~ility. Thus, there is a difficulty that the CADD model no , longer accur~tely represents the environment constructed therefrom.
~:CADD~models could be used to record the "as-built" or 9'as-is"
position, shape:~and orientation data of the components of an environment, for example, an existing manufactured product or indust~ial ~acility, if these data could be determined.
;
$UBS~ I l'UTE SHEET
2 1 1 1 1 1 7 PCr/11~92/0~
SUMMARY OF THE I~V~;N~1~10N
The present inventisn overcomes the above difficulty by pro~iding a system and method which recovers ~he position and orientation (spatial data) and the shape and operational characteristics (descriptive data) of objects forming an environment. This data may then be transformed into a CADD model of the as-built or as-is environment.
The invention includes a data gathering apparatus and may also include a model building apparatus. The data ~athering apparatus determines and records th~ position, orientation, shape and, if applicable, operational characteristics of objects. The model building apparatus transforms th~se spatial/descriptive data into a CADD model. When complete, this CADD model is an accurate depiction of the spatial relationships and descriptions of all objects within an environment. The modeled environment can then be viewed via a computer monitor or other output device.
The data gathering apparatus incorporates a position and measurement system, such as that disclosed in Beliveau et al. and Dornbusch et al. described above. The data gathering apparatus may : 20 also include a shape sensor which is capable of sensing the shape of objects. A separate operational characteristic sensor may also ~: ~ be included to measure any distinguishing operational chaxacteristics, such as temperature or material composition, which aids in identifying a specific object from neighboxing objects of 2S similar shape. The data gathering apparatus collects any or all of the shape, position, orientation and operational data for any or all objects in:an environment.
: The:spatial/descriptive data may be tran~ferred to a model ,~ , building~ apparatus either in real time through an on-line 30 : communication device, or at a later time from stored memory.
The ~hape and opera~ional characteristics data permit the model building apparatus to identify objects. This identification may ibè achieved through comparison of the recovered descripti~e data with detailed descriptive data of objects contained within software 35 : object li~xaries. Software o~ject libraries would contain the de~criptive data for some or all of the obiects which are expected ;: within a particular environment. For exampl~, for an environment including a chemical processing plant, the software libraries would : likely contain descriptive data for pipes, valves, pumps and the :: 2 SIJ~ JTE SHEET
~ 092t22%32 2 1 1 1 1 1 7 PCT/US92/~S132 lik~, of many sizes and shapes. Once an object identification is made t the de~ailed descriptive data is placed in the CADD model using the corresponding spatial data provided by the data gathering apparatus. This reduces the amount of data collection required in the field ~o provide a detailed CADD model of that particular environment, and henoe will reduce the time required to construct such models.
One pr~ferred embodiment of the data ~athering apparatus includes a hand-held rod. A touch sensor is attached to one end of the rod and senses when proper contact is made with an object.
A shape sensor and an operational sensor are also attached to the rod. The shape sensor may include, for example, a sonar, while the operational sensor may include, for example, a thermometer. These sensors provide the descripti~e data necessary for identification of objects. It is also necessary to know the azimuth and angle of inclination of the rod in order to properly determine the spatial data of objects. To this end, tilt sen~ors may be provided on the rod to dete~mine th~ angle of inclination of the rod. Further, a~ial rotation data can be useful in determining orientation. The 0 tilt sensors may also determine the axial rotation of the rod.
: Multiple positioning receivers allow the determination of both the :azimuth and angle of inclination of the rod. A combination of tilt sensors and posi~ioning receivers on the rod can be used~
: Acc~rding to a pr~ferr~d embodiment of the method of the invention, the operator~carries the data gathering apparatus, e.g., rsd,~ and systematically places the touch sensor on the objects forming the~ ~nvironment. The spa~ial/descriptiYe data of each object i~ deter~ined and stored. The data then may be transferred to a model building:apparatus. The received shape and operational data are used to identify objects. Once an object is identified, its position and orienta~ion are used to place the descriptive data ~ fqr th~ ob;ject in the CADD model. These steps are repeated until : all relevant obje~ts of the real environment have been placed in t~e CAD~ model.
35Simpler versions of the system and method of the invention are ~ nvisioned. For example, it is contemplated that an operator may ; input the shape and/or operational characteristics of the object being position, for ~xample, 10" pipe, hot, directly into the model buildi~g apparatus. Then the position and orientation would be ~: 3 5U135~ ITE SHIEET
WOQ2/2~32 ~ PCT/US92/05~
determined by the data collection apparatus. Once the corresponding position and orientation data are transmitted to the model buildin~ apparatus, the object can be included in the CADD
model.
BRIEF DESCRIPTTON OF THE DRAWINGS
The above aspects of the present invention can be seen from the attached dr~wings, in which:
Figure 1 is a schematic drawing of a data gathering apparatus in accordance with a preferred embodiment of thP invention co~lecting data of an object:
Figure 2 is a schematic view illustrating the data gathering apparatus shown in Figure 1:
Figure 3 is a schematic view illustrating a model building apparatus in accordance with a preferred embodiment of the invention;
Figure 4 is a schematic view illustrating the data gathering ap~aratus shown in Figure 2 fitted with a wheel attachment for mea~urement of co~tour~d surfaces in accordance with the invention;
2~ Figure S is a CC-h~r'tiC view illustrating the calculation of the position of the:data gathering appaxatus in accordan~e with the , : in~ention; and Figur~ 6 is a schematic view illustrating a po~ition and measurement syst~m in con~unction with the data gathering apparatus shown in Figure 2.
:.DETAILED ~ESCRIPTION OF THE ~k~P~K~;v EMBODIMENTS
:: A~spatial measure~ent~and recovery system in accordance with ; a~preferred e~bodiDent~of the invention is shown in Fi~ure l~
:30 Thxoughout the figuresr~like:numerals are used to designate like eleme~ts.~
The data gathering apparatus 100~gathers spatial~descriptive data of objects ~o~ming an environment for creating a "three-;~?~ional map" of the environment~ A real time position35 ~ determination system is inte~rated into the data gathering apparatus 100,~as will be~explained in mor~ detail belowO To this end, the;data gathering apparatus includes one or more position sensors 110 ~shown in Fi~ure 2).
~:~ 4 SUBSTITUTE SHEET
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'~'D92/22~32 21 1111 7 PffCT/US9f2J05132 One preferred embodiment of the data gathering apparatus as showr~ff in Figure 2 includes a rod 108 which is adapted to be hand held by an operator. It is contemplated that the rod may include flexible joints if the angular rotation of the joints is accounted for when determining position and orientation data~ The operator places the tip of the rod 108 on an object for which data is to be gatherffPd. Upon beinfg placed on the object 300, the touch sensor 112 is triggered, which activates the compuker/data storage device 120.
The computer/data storage device 120 is preferably connected to the rod via a commffunications link, such as via the cable shown in Fiff~ure 2. Alternatively, the computer/data storage device 120 may be mountfff~d on the rod itself. The co~u~u~er/data storage device 1~0 serves as an interface for the operator tOf enter data and to calibrate the positioning system and sensors~ The operator may also communicate descr~ptive data ~i.e,, shape and operational characteristic data~ and spatial data (iOe., position and orif~ntation data) via a communications link, for example, by voice over a "walkie-talkie" system ~not shown) ~ to another operator who ZO inputs the data into another apparatus for storage and/or data manipulation. It i5 contemp7ated that the cf~mputer/data storage ~ device 120 may also have the capability to store spatial data :~ ~ a~d~or df~scriptive data of objects itself.
The computer/data storage device lZO selectiv~ly activates a shape sensfDr 114 and an operational senf~tor ll~~ The shape sen~or 114 can be o~ any suitable type which provide~ data which will distinf~uish thfe surface~features of the object 300. The shape ensor 114 may al80 be capable of providing data rfefgarding interior feature~. In one preferred embodiment, a sonar device may be usfeffd ; 30 as the shape senso~ . Such a sonar de~iff~e could i~clude one or ~ :more direct:ional audio tr~fffn~dllc~rs~ and receivers (not shown).
!~ f ~Difrectional aufdio signals would be aimed at different pointsff~n the O~ff; ect ts determine the relative distance to the points. Thfe distance to the points would give an inffi~ication of the shape of the ~: 35 object. In addition, a soundinq devire (not shown) in physical : contact with the object 300 would transmit sound into the o~ject and rereive the resultant reflected sound. The sounding device may ~: thus determine the thickness of materials composing the obje~t at :
~ 5 SUBSTIT~ITE~: 5~EET
W~ 92/22832 2 1 ~ 1 1 1 7 PCT~U~g2/0~
the point of contact. It is also envisioned that such a sounding device may be incorporated into the touch sensor 112.
The data gathering apparatus 100 may include an operational characteristic sensor 116. The operational characteristic sensor 116 determines one or more operational characteristics of the object 300. Such operational characteristics may be used to distinguish an objec~ from neighboring objects of similar shape.
Operational characteristics which could be used as distin~l;~hing traits may include, for example, temperature, material composition, electrical current and/or color or the like. In one preferred embodiment in accordance with the present invention, a ther~ometer is used as operational characteristic sensor 116 to distinguish objec~s having unique operational temperatures or temperature ranges. In another preferred embodiment, a hardness testing device I5 could be use~ as the operational characteristic sensor 116 to distinguish objects composed of outer materials having unique material hardness or material hardness range~. In a further preferred embodiment, a magnetic flux detector could be used as the operational characteristic sensor 116 to distinguish objects carrying differ2nt electrical currents. In another preferred :~ embodiment, a camara m~y be used as the operational characteristic sensor 116 to disti~guish objects differing in color. It is to be ~;~ ;; understood that any desired operational characteristic and any corre~ponding op~rational char~cteristic sensor 116 may be used in connection with the system an~ method of the present invention.
The data qathering apparatus 10~ may be fitted with various specialized at~achments suitabl for specialized data gathering.
For examplet~as shown~in Figure 4,:a wheel attachment may be u~ed to enhance the gathering o~ data over contoured surfaces.
As~shown in:Fi~ure 5~, two position sensors 110 may be attached along the axis of the rod. Two position sensors used in this manner will proyide the minimum information necessary to determine the position of the tip 130 of the data gathering apparatus 100.
In accordance wi~h the in~ention, the position of the position sensors 110 along ~he rod 108 are determined in reference to at : ; : lea t two fixed station~ 50~, a~ shown in Figure 6. EaGh fixed '~ : stati~on preferably prQduces a set or multiple sets of counter-rotating beams which rotate at a constant angular velocity. Such :~ counter-rotating beams can be produced using multiple rotating ~:~; 6 Sll~ JTE SHEET
'''~92/22832 2 1 1 1 1 1 ~ PcT/us92/o5l32 heads and strategically placed reflective surfaces, as shown in the Dornbusch ~t al. application referred to above.
~ ach fix~d station 500 preferably includes a la~er which produces at least one primary laser beam and at least one secondary beam w~ich are counter-rotated about an axis. The primary laser beam has a predetermined ang~e of di~ergence (i.e., spread) which is inclined at a predetermined angle from the rotational axis~ The secondary beam has the same divergence and may have the same inclination as the primary beam, but rotatas in the opposite direction.
When the position sensor 110 is crossed by the two laser beams, a horizontal angle can be determined from the time dif~erence between the time of crossing of the primary and secondary beams.
Once these horizontal angles are known for three fixed stations 500, the point of intersection of three plan~s, and thus the three-dimensional po ition of the position sensor 110 can b~ determined.
~ lternatively, if the fixed stations 500 each produce two primAry laser beams a~d one or mor~, secondary beams, only two fixed 20 stations are required to determine the position of the po ition sen~or~ 110 of the data gathering apparatus 100.
As shown in Figure 5, once the position of the positi~ning ~:~ senssrs 110 ha~e been dete~mined, the position of the tip of the rod can be determined as follows:
X = L/D(X2 - X1) + ~2 y = L/D(Y2 - Y,) ~ Y-Z = L/D ( 2~2 - ~1 ) + Zl ~: The orientat;ion of an object can be determined if the position of three non-colinea~ points on the object are known. When the 3~ data collection de~ice touches an object, the location of a single point i8 determined by the positioning system employed in the data ;j gal~hering apparatus 100. The position of additional points can be ; generated through analy~is of the shape da~a determined by the shape ~ensor 114:. The accuracy of the determined orientation will increase as the number of positions on the object from which the ~; position data and shape data are tak~n increases.
Once the positio~, orientation, shape and operational characteristic data are determined, they are preferably immediately stored in the computer/data storage device 120, or sent to the :
$UE~S~lTa)TE 5HEE~;T
W092/2~32 2 ~ 1~1 1 1 l PCTlVS92/05 L
model building apparatus 200 via the communication links 120 and 220, as shown in Figure 3. The model ~uilding apparatus 200 stores the incoming spa~ial/descriptive data for the current object 300.
The descriptive data is used ~o identify the object fro~ a li~t of detailed descriptive data (e.g., actual design data) of previously recorded objects.
This list of detailed descriptive data is preferably in the form of software object libraries contained within the model building apparatus 200. Small distances can ~enerally be accurately mea~ured and precisely reproduced using commonly available instrumentation and tools, such as calipers, computer numerical controlled "CNCI' machining e~uipment and the like.
~owever, ~raditionally as the size of objects and the distance between objects increases, the ability to quickly and accurately measure these larger distances decreases. Th~ object libraries of the model building apparatus 200 may contain the small dimensional information, such as the design shape data or production shape data, which is known to be accurate or which can be presumed to be aGcurate to the minimum accuracy required ~or the work at hand.
~20 I~ this way, the model building apparatus 200 can use the shape :data provided by the data gathering apparatus to identify the data file in the object libra~y which correspond to the object 300.
Alternatively, the operator performiny the data gathering can ente~r an identification code for the object into the compu~er/data~; 25 s~orage device or directly into the model building appar,atus 200.
This code would ide~tify the appropriate descriptive data file without the need ~or analysis of the shape data of the object 300.
The identification code could be a manufacturer's part number, a desi~n component~number or any code which uniguely identified the object 300.
Once the descriptive:data for the object is determined, the ~:~ mod~l building~apparatus 200 links the descriptive data to the position and orientation data generated by the data gathering apparatus 100.
In operation, an operator systematically places the data gàthering apparatus 100 on the objects composing the environment in the spatial/descriptive data is desired. The : spatial/descripti~e date for each object is stored by the computer/data storage device 120. Alternatively, the : 8 SlJB~ aJTE: 51~ ;ET
~92~2~32 ~ 7 PCT/USg2/05132 spatial/descriptive data is directly transmitted to the model building apparatus 200. The model buildi~g apparatus 200 recor~s the spatial/descriptive data~ matches the descriptive data to the reference data contained within the object libraries and places the S CADD image of the object in the CADD model of the environment.
The above is for illustrative purposes only. Modification can be made, particularly with regard to size, shape and arrangement of parts, within the scope of the invention as de~ined by the appended claims. For example, it i5 envisioned that position-reflectors or position-transponders could be used in place of the position sensors 110, wherein a position and measurement system would be employed in the data gathering apparatus 100 which gathers radiation emissions such as laser or radio beams at the transmitter.
Further, ~he invention is not limited to creating CADD models.
It is also en~isioned that the system and method of the invention can be used in navigational systems, for example, to allow robotic vehicles to navigate within their environments.
.
~ ~, ' ~ 1' ' 1 ! ' ~, :: ' '~
~:
SUB~ UTE SHEEl~
SUMMARY OF THE I~V~;N~1~10N
The present inventisn overcomes the above difficulty by pro~iding a system and method which recovers ~he position and orientation (spatial data) and the shape and operational characteristics (descriptive data) of objects forming an environment. This data may then be transformed into a CADD model of the as-built or as-is environment.
The invention includes a data gathering apparatus and may also include a model building apparatus. The data ~athering apparatus determines and records th~ position, orientation, shape and, if applicable, operational characteristics of objects. The model building apparatus transforms th~se spatial/descriptive data into a CADD model. When complete, this CADD model is an accurate depiction of the spatial relationships and descriptions of all objects within an environment. The modeled environment can then be viewed via a computer monitor or other output device.
The data gathering apparatus incorporates a position and measurement system, such as that disclosed in Beliveau et al. and Dornbusch et al. described above. The data gathering apparatus may : 20 also include a shape sensor which is capable of sensing the shape of objects. A separate operational characteristic sensor may also ~: ~ be included to measure any distinguishing operational chaxacteristics, such as temperature or material composition, which aids in identifying a specific object from neighboxing objects of 2S similar shape. The data gathering apparatus collects any or all of the shape, position, orientation and operational data for any or all objects in:an environment.
: The:spatial/descriptive data may be tran~ferred to a model ,~ , building~ apparatus either in real time through an on-line 30 : communication device, or at a later time from stored memory.
The ~hape and opera~ional characteristics data permit the model building apparatus to identify objects. This identification may ibè achieved through comparison of the recovered descripti~e data with detailed descriptive data of objects contained within software 35 : object li~xaries. Software o~ject libraries would contain the de~criptive data for some or all of the obiects which are expected ;: within a particular environment. For exampl~, for an environment including a chemical processing plant, the software libraries would : likely contain descriptive data for pipes, valves, pumps and the :: 2 SIJ~ JTE SHEET
~ 092t22%32 2 1 1 1 1 1 7 PCT/US92/~S132 lik~, of many sizes and shapes. Once an object identification is made t the de~ailed descriptive data is placed in the CADD model using the corresponding spatial data provided by the data gathering apparatus. This reduces the amount of data collection required in the field ~o provide a detailed CADD model of that particular environment, and henoe will reduce the time required to construct such models.
One pr~ferred embodiment of the data ~athering apparatus includes a hand-held rod. A touch sensor is attached to one end of the rod and senses when proper contact is made with an object.
A shape sensor and an operational sensor are also attached to the rod. The shape sensor may include, for example, a sonar, while the operational sensor may include, for example, a thermometer. These sensors provide the descripti~e data necessary for identification of objects. It is also necessary to know the azimuth and angle of inclination of the rod in order to properly determine the spatial data of objects. To this end, tilt sen~ors may be provided on the rod to dete~mine th~ angle of inclination of the rod. Further, a~ial rotation data can be useful in determining orientation. The 0 tilt sensors may also determine the axial rotation of the rod.
: Multiple positioning receivers allow the determination of both the :azimuth and angle of inclination of the rod. A combination of tilt sensors and posi~ioning receivers on the rod can be used~
: Acc~rding to a pr~ferr~d embodiment of the method of the invention, the operator~carries the data gathering apparatus, e.g., rsd,~ and systematically places the touch sensor on the objects forming the~ ~nvironment. The spa~ial/descriptiYe data of each object i~ deter~ined and stored. The data then may be transferred to a model building:apparatus. The received shape and operational data are used to identify objects. Once an object is identified, its position and orienta~ion are used to place the descriptive data ~ fqr th~ ob;ject in the CADD model. These steps are repeated until : all relevant obje~ts of the real environment have been placed in t~e CAD~ model.
35Simpler versions of the system and method of the invention are ~ nvisioned. For example, it is contemplated that an operator may ; input the shape and/or operational characteristics of the object being position, for ~xample, 10" pipe, hot, directly into the model buildi~g apparatus. Then the position and orientation would be ~: 3 5U135~ ITE SHIEET
WOQ2/2~32 ~ PCT/US92/05~
determined by the data collection apparatus. Once the corresponding position and orientation data are transmitted to the model buildin~ apparatus, the object can be included in the CADD
model.
BRIEF DESCRIPTTON OF THE DRAWINGS
The above aspects of the present invention can be seen from the attached dr~wings, in which:
Figure 1 is a schematic drawing of a data gathering apparatus in accordance with a preferred embodiment of thP invention co~lecting data of an object:
Figure 2 is a schematic view illustrating the data gathering apparatus shown in Figure 1:
Figure 3 is a schematic view illustrating a model building apparatus in accordance with a preferred embodiment of the invention;
Figure 4 is a schematic view illustrating the data gathering ap~aratus shown in Figure 2 fitted with a wheel attachment for mea~urement of co~tour~d surfaces in accordance with the invention;
2~ Figure S is a CC-h~r'tiC view illustrating the calculation of the position of the:data gathering appaxatus in accordan~e with the , : in~ention; and Figur~ 6 is a schematic view illustrating a po~ition and measurement syst~m in con~unction with the data gathering apparatus shown in Figure 2.
:.DETAILED ~ESCRIPTION OF THE ~k~P~K~;v EMBODIMENTS
:: A~spatial measure~ent~and recovery system in accordance with ; a~preferred e~bodiDent~of the invention is shown in Fi~ure l~
:30 Thxoughout the figuresr~like:numerals are used to designate like eleme~ts.~
The data gathering apparatus 100~gathers spatial~descriptive data of objects ~o~ming an environment for creating a "three-;~?~ional map" of the environment~ A real time position35 ~ determination system is inte~rated into the data gathering apparatus 100,~as will be~explained in mor~ detail belowO To this end, the;data gathering apparatus includes one or more position sensors 110 ~shown in Fi~ure 2).
~:~ 4 SUBSTITUTE SHEET
:~ :
~ ~i ~.".,~.. ,'',d r~.d. ~ ,d ,~
'~'D92/22~32 21 1111 7 PffCT/US9f2J05132 One preferred embodiment of the data gathering apparatus as showr~ff in Figure 2 includes a rod 108 which is adapted to be hand held by an operator. It is contemplated that the rod may include flexible joints if the angular rotation of the joints is accounted for when determining position and orientation data~ The operator places the tip of the rod 108 on an object for which data is to be gatherffPd. Upon beinfg placed on the object 300, the touch sensor 112 is triggered, which activates the compuker/data storage device 120.
The computer/data storage device 120 is preferably connected to the rod via a commffunications link, such as via the cable shown in Fiff~ure 2. Alternatively, the computer/data storage device 120 may be mountfff~d on the rod itself. The co~u~u~er/data storage device 1~0 serves as an interface for the operator tOf enter data and to calibrate the positioning system and sensors~ The operator may also communicate descr~ptive data ~i.e,, shape and operational characteristic data~ and spatial data (iOe., position and orif~ntation data) via a communications link, for example, by voice over a "walkie-talkie" system ~not shown) ~ to another operator who ZO inputs the data into another apparatus for storage and/or data manipulation. It i5 contemp7ated that the cf~mputer/data storage ~ device 120 may also have the capability to store spatial data :~ ~ a~d~or df~scriptive data of objects itself.
The computer/data storage device lZO selectiv~ly activates a shape sensfDr 114 and an operational senf~tor ll~~ The shape sen~or 114 can be o~ any suitable type which provide~ data which will distinf~uish thfe surface~features of the object 300. The shape ensor 114 may al80 be capable of providing data rfefgarding interior feature~. In one preferred embodiment, a sonar device may be usfeffd ; 30 as the shape senso~ . Such a sonar de~iff~e could i~clude one or ~ :more direct:ional audio tr~fffn~dllc~rs~ and receivers (not shown).
!~ f ~Difrectional aufdio signals would be aimed at different pointsff~n the O~ff; ect ts determine the relative distance to the points. Thfe distance to the points would give an inffi~ication of the shape of the ~: 35 object. In addition, a soundinq devire (not shown) in physical : contact with the object 300 would transmit sound into the o~ject and rereive the resultant reflected sound. The sounding device may ~: thus determine the thickness of materials composing the obje~t at :
~ 5 SUBSTIT~ITE~: 5~EET
W~ 92/22832 2 1 ~ 1 1 1 7 PCT~U~g2/0~
the point of contact. It is also envisioned that such a sounding device may be incorporated into the touch sensor 112.
The data gathering apparatus 100 may include an operational characteristic sensor 116. The operational characteristic sensor 116 determines one or more operational characteristics of the object 300. Such operational characteristics may be used to distinguish an objec~ from neighboring objects of similar shape.
Operational characteristics which could be used as distin~l;~hing traits may include, for example, temperature, material composition, electrical current and/or color or the like. In one preferred embodiment in accordance with the present invention, a ther~ometer is used as operational characteristic sensor 116 to distinguish objec~s having unique operational temperatures or temperature ranges. In another preferred embodiment, a hardness testing device I5 could be use~ as the operational characteristic sensor 116 to distinguish objects composed of outer materials having unique material hardness or material hardness range~. In a further preferred embodiment, a magnetic flux detector could be used as the operational characteristic sensor 116 to distinguish objects carrying differ2nt electrical currents. In another preferred :~ embodiment, a camara m~y be used as the operational characteristic sensor 116 to disti~guish objects differing in color. It is to be ~;~ ;; understood that any desired operational characteristic and any corre~ponding op~rational char~cteristic sensor 116 may be used in connection with the system an~ method of the present invention.
The data qathering apparatus 10~ may be fitted with various specialized at~achments suitabl for specialized data gathering.
For examplet~as shown~in Figure 4,:a wheel attachment may be u~ed to enhance the gathering o~ data over contoured surfaces.
As~shown in:Fi~ure 5~, two position sensors 110 may be attached along the axis of the rod. Two position sensors used in this manner will proyide the minimum information necessary to determine the position of the tip 130 of the data gathering apparatus 100.
In accordance wi~h the in~ention, the position of the position sensors 110 along ~he rod 108 are determined in reference to at : ; : lea t two fixed station~ 50~, a~ shown in Figure 6. EaGh fixed '~ : stati~on preferably prQduces a set or multiple sets of counter-rotating beams which rotate at a constant angular velocity. Such :~ counter-rotating beams can be produced using multiple rotating ~:~; 6 Sll~ JTE SHEET
'''~92/22832 2 1 1 1 1 1 ~ PcT/us92/o5l32 heads and strategically placed reflective surfaces, as shown in the Dornbusch ~t al. application referred to above.
~ ach fix~d station 500 preferably includes a la~er which produces at least one primary laser beam and at least one secondary beam w~ich are counter-rotated about an axis. The primary laser beam has a predetermined ang~e of di~ergence (i.e., spread) which is inclined at a predetermined angle from the rotational axis~ The secondary beam has the same divergence and may have the same inclination as the primary beam, but rotatas in the opposite direction.
When the position sensor 110 is crossed by the two laser beams, a horizontal angle can be determined from the time dif~erence between the time of crossing of the primary and secondary beams.
Once these horizontal angles are known for three fixed stations 500, the point of intersection of three plan~s, and thus the three-dimensional po ition of the position sensor 110 can b~ determined.
~ lternatively, if the fixed stations 500 each produce two primAry laser beams a~d one or mor~, secondary beams, only two fixed 20 stations are required to determine the position of the po ition sen~or~ 110 of the data gathering apparatus 100.
As shown in Figure 5, once the position of the positi~ning ~:~ senssrs 110 ha~e been dete~mined, the position of the tip of the rod can be determined as follows:
X = L/D(X2 - X1) + ~2 y = L/D(Y2 - Y,) ~ Y-Z = L/D ( 2~2 - ~1 ) + Zl ~: The orientat;ion of an object can be determined if the position of three non-colinea~ points on the object are known. When the 3~ data collection de~ice touches an object, the location of a single point i8 determined by the positioning system employed in the data ;j gal~hering apparatus 100. The position of additional points can be ; generated through analy~is of the shape da~a determined by the shape ~ensor 114:. The accuracy of the determined orientation will increase as the number of positions on the object from which the ~; position data and shape data are tak~n increases.
Once the positio~, orientation, shape and operational characteristic data are determined, they are preferably immediately stored in the computer/data storage device 120, or sent to the :
$UE~S~lTa)TE 5HEE~;T
W092/2~32 2 ~ 1~1 1 1 l PCTlVS92/05 L
model building apparatus 200 via the communication links 120 and 220, as shown in Figure 3. The model ~uilding apparatus 200 stores the incoming spa~ial/descriptive data for the current object 300.
The descriptive data is used ~o identify the object fro~ a li~t of detailed descriptive data (e.g., actual design data) of previously recorded objects.
This list of detailed descriptive data is preferably in the form of software object libraries contained within the model building apparatus 200. Small distances can ~enerally be accurately mea~ured and precisely reproduced using commonly available instrumentation and tools, such as calipers, computer numerical controlled "CNCI' machining e~uipment and the like.
~owever, ~raditionally as the size of objects and the distance between objects increases, the ability to quickly and accurately measure these larger distances decreases. Th~ object libraries of the model building apparatus 200 may contain the small dimensional information, such as the design shape data or production shape data, which is known to be accurate or which can be presumed to be aGcurate to the minimum accuracy required ~or the work at hand.
~20 I~ this way, the model building apparatus 200 can use the shape :data provided by the data gathering apparatus to identify the data file in the object libra~y which correspond to the object 300.
Alternatively, the operator performiny the data gathering can ente~r an identification code for the object into the compu~er/data~; 25 s~orage device or directly into the model building appar,atus 200.
This code would ide~tify the appropriate descriptive data file without the need ~or analysis of the shape data of the object 300.
The identification code could be a manufacturer's part number, a desi~n component~number or any code which uniguely identified the object 300.
Once the descriptive:data for the object is determined, the ~:~ mod~l building~apparatus 200 links the descriptive data to the position and orientation data generated by the data gathering apparatus 100.
In operation, an operator systematically places the data gàthering apparatus 100 on the objects composing the environment in the spatial/descriptive data is desired. The : spatial/descripti~e date for each object is stored by the computer/data storage device 120. Alternatively, the : 8 SlJB~ aJTE: 51~ ;ET
~92~2~32 ~ 7 PCT/USg2/05132 spatial/descriptive data is directly transmitted to the model building apparatus 200. The model buildi~g apparatus 200 recor~s the spatial/descriptive data~ matches the descriptive data to the reference data contained within the object libraries and places the S CADD image of the object in the CADD model of the environment.
The above is for illustrative purposes only. Modification can be made, particularly with regard to size, shape and arrangement of parts, within the scope of the invention as de~ined by the appended claims. For example, it i5 envisioned that position-reflectors or position-transponders could be used in place of the position sensors 110, wherein a position and measurement system would be employed in the data gathering apparatus 100 which gathers radiation emissions such as laser or radio beams at the transmitter.
Further, ~he invention is not limited to creating CADD models.
It is also en~isioned that the system and method of the invention can be used in navigational systems, for example, to allow robotic vehicles to navigate within their environments.
.
~ ~, ' ~ 1' ' 1 ! ' ~, :: ' '~
~:
SUB~ UTE SHEEl~
Claims (15)
1. A spatial measurement recovery system for determining at least one of position, orientation, shape and operational characteristics of an environment, comprising:
means for gathering data regarding at least one object forming the environment, said means for gathering data including at least one position sensor; and means for manipulating the data gathered by said means for gathering data so as to create a three-dimensional map of the environment.
means for gathering data regarding at least one object forming the environment, said means for gathering data including at least one position sensor; and means for manipulating the data gathered by said means for gathering data so as to create a three-dimensional map of the environment.
2. A system as in claim 1, wherein the means for manipulating the data is a computer which creates a CADD model of the environment.
3. A system as in claim 1, wherein said means for gathering data is portable.
4. A system as in claim 3, wherein said means for gathering data includes a rod having at least one position sensor formed thereon.
5. A system as in claim 1, wherein said means for gathering data includes a shape sensor.
6. A system as in claim 5, wherein said shape sensor is a sonar device.
7. A system as in claim 1, wherein said means for gathering data includes an operational characteristic sensor.
8. A system as in claim 7, wherein said operational characteristic sensor is selected from the group consisting of a thermometer, a hardness tester, a magnetic flux detector and a camera.
9. A system as in claim 4, wherein said rod includes a touch sensor.
10. A system as in claim 1, wherein said means for manipulating data includes a model building apparatus having a computer workstation and a communications device, wherein said means for manipulating data receives the position, orientation, shape and operational characteristics via said communications device from said means for gathering data and transforms these data into a computerized model of the environment.
11. A system as in claim 1, wherein said means for gathering data includes a plurality of position sensors.
12. A system as in claim 11, wherein said plurality of sensors operate in conjunction with at least two fixed stations to determine the position of an end of said rod corresponding to a position within the environment.
13. A system as in claim 2, wherein said computer contains an object library having reference shape and operational characteristic data for known objects, and wherein the shape and operational characteristic data gathered by said means for gathering data is compared with the reference shape and operational characteristic data to identify an unknown object.
14. A method for determining at least one of position, orientation, shape and operational characteristics of an environment, comprising the steps of:
systematically gathering spatial and descriptive data regarding objects forming the environment;
manipulating the data gathered so as to create a map of the environment.
systematically gathering spatial and descriptive data regarding objects forming the environment;
manipulating the data gathered so as to create a map of the environment.
15. A method as in claim 14, wherein said step of manipulating the data includes:
storing the data in a model building apparatus:
matching any shape and operational characteristic data to reference data contained within object libraries in said model building apparatus so as to identify objects within the environment; and creating CADD images in a CADD model corresponding to the objects within the environment.
storing the data in a model building apparatus:
matching any shape and operational characteristic data to reference data contained within object libraries in said model building apparatus so as to identify objects within the environment; and creating CADD images in a CADD model corresponding to the objects within the environment.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US714,891 | 1991-06-17 | ||
| US07/714,891 US5247487A (en) | 1991-06-17 | 1991-06-17 | Spatial measurement recovery system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2111117A1 CA2111117A1 (en) | 1992-12-23 |
| CA2111117C true CA2111117C (en) | 1998-01-20 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002111117A Expired - Fee Related CA2111117C (en) | 1991-06-17 | 1992-06-17 | Spatial measurement recovery system |
Country Status (7)
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| US (1) | US5247487A (en) |
| EP (1) | EP0592515B1 (en) |
| JP (1) | JP3252965B2 (en) |
| AT (1) | ATE208903T1 (en) |
| CA (1) | CA2111117C (en) |
| DE (1) | DE69232203T2 (en) |
| WO (1) | WO1992022832A1 (en) |
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| US5579102A (en) * | 1991-06-17 | 1996-11-26 | Spatial Positioning Systems, Inc. | Transmitter and receiver units for spatial position measurement system |
| US5729475A (en) * | 1995-12-27 | 1998-03-17 | Romanik, Jr.; Carl J. | Optical system for accurate monitoring of the position and orientation of an object |
| US5675514A (en) * | 1996-04-10 | 1997-10-07 | Lefebvre; Guy | Telemetric spacial data recorder |
| US5771978A (en) * | 1996-06-05 | 1998-06-30 | Kabushiki Kaisha Topcon | Grading implement elevation controller with tracking station and reference laser beam |
| AU4769097A (en) * | 1996-10-23 | 1998-05-15 | Romeo Hudon | Telemetric spacial data recorder |
| ATE314629T1 (en) * | 1998-10-13 | 2006-01-15 | Arc Second Inc | OPTICAL TRANSMITTER WITH ROTATING HEAD FOR POSITION MEASURING SYSTEM |
| US6108271A (en) * | 1998-12-10 | 2000-08-22 | Erskine College | Remote control device for controlling electronic devices |
| US6630993B1 (en) | 1999-03-22 | 2003-10-07 | Arc Second Inc. | Method and optical receiver with easy setup means for use in position measurement systems |
| WO2000057132A1 (en) * | 1999-03-22 | 2000-09-28 | Arc Second, Inc. | Method for creating a user-selectable coordinate frame |
| EP1166044A1 (en) * | 1999-03-22 | 2002-01-02 | Arc Second, Inc | Method for establishing a coordinate system |
| WO2000057133A1 (en) * | 1999-03-22 | 2000-09-28 | Arc Second, Inc. | Calibration of optical transmitter for position measurement systems |
| US6662103B1 (en) | 1999-03-22 | 2003-12-09 | Arc Second Inc. | Method and system for creating a user-selectable arbitrary coordinate frame |
| US6519029B1 (en) * | 1999-03-22 | 2003-02-11 | Arc Second, Inc. | Low cost transmitter with calibration means for use in position measurement systems |
| DE19962997B4 (en) * | 1999-12-24 | 2010-06-02 | Robert Bosch Gmbh | Method for calibrating a sensor system |
| FR2805350B1 (en) * | 2000-02-18 | 2003-07-11 | Scertab Soc Civ Ile D Etudes E | TELEMETRY EQUIPMENT FOR BI- OR THREE-DIMENSIONAL MAPPING OF A VOLUME |
| US6501543B2 (en) * | 2000-02-28 | 2002-12-31 | Arc Second, Inc. | Apparatus and method for determining position |
| US6545751B2 (en) * | 2000-02-28 | 2003-04-08 | Arc Second, Inc. | Low cost 2D position measurement system and method |
| US20010038447A1 (en) * | 2000-03-10 | 2001-11-08 | Detweiler Philip L. | Versatile transmitter and receiver for position measurement |
| JP2004505263A (en) * | 2000-08-01 | 2004-02-19 | エスリング・ミルコ | Measuring device and measuring method for measuring distance and / or position |
| DE102004053686A1 (en) * | 2004-11-03 | 2006-05-04 | Essling, Mirko | Laser receiving device with improved accuracy and lower power consumption |
| CN101490505B (en) * | 2006-07-12 | 2012-06-06 | 天宝导航有限公司 | Handheld laser light detector with height correction, using a GPS receiver to provide two-dimensional position data |
| KR100750897B1 (en) * | 2006-09-26 | 2007-08-22 | 삼성중공업 주식회사 | Dimension measurement system and rescale method using indoor global positioning system |
| US7576871B2 (en) * | 2006-10-03 | 2009-08-18 | Storm Thomas W | Apparatus and method for measuring volumes |
| GB0625442D0 (en) * | 2006-12-20 | 2007-01-31 | Csl Surveys Stevenage Ltd | Profiling device |
| US8711335B2 (en) | 2011-06-28 | 2014-04-29 | Nikon Corporation | Stroboscopic light source for a transmitter of a large scale metrology system |
| US10286308B2 (en) | 2014-11-10 | 2019-05-14 | Valve Corporation | Controller visualization in virtual and augmented reality environments |
| US11134864B2 (en) | 2016-07-13 | 2021-10-05 | Alexei L. Vyssotski | Tracking method and system for small animal research |
| US20200285639A1 (en) * | 2019-03-05 | 2020-09-10 | At&T Intellectual Property I, L.P. | Apparatus and method to isolate vectors in an arbitrarily large n-space |
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| GB2152320A (en) * | 1983-12-07 | 1985-07-31 | Robert James Siddall | Position location system |
| DE3717708A1 (en) * | 1987-05-23 | 1988-12-08 | Prakla Seismos Ag | METHOD FOR DETERMINING THE LOCATION OF CABLE SECTIONS TOWED BEHIND A SHIP |
| US5121333A (en) * | 1989-06-09 | 1992-06-09 | Regents Of The University Of Minnesota | Method and apparatus for manipulating computer-based representations of objects of complex and unique geometry |
| JP2878409B2 (en) * | 1989-09-04 | 1999-04-05 | 株式会社リコー | 3D object imaging method |
-
1991
- 1991-06-17 US US07/714,891 patent/US5247487A/en not_active Expired - Lifetime
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1992
- 1992-06-17 CA CA002111117A patent/CA2111117C/en not_active Expired - Fee Related
- 1992-06-17 AT AT92914081T patent/ATE208903T1/en not_active IP Right Cessation
- 1992-06-17 EP EP92914081A patent/EP0592515B1/en not_active Expired - Lifetime
- 1992-06-17 JP JP50110593A patent/JP3252965B2/en not_active Expired - Lifetime
- 1992-06-17 DE DE69232203T patent/DE69232203T2/en not_active Expired - Fee Related
- 1992-06-17 WO PCT/US1992/005132 patent/WO1992022832A1/en active IP Right Grant
Also Published As
| Publication number | Publication date |
|---|---|
| DE69232203T2 (en) | 2002-08-14 |
| EP0592515A4 (en) | 1995-05-17 |
| EP0592515A1 (en) | 1994-04-20 |
| US5247487A (en) | 1993-09-21 |
| JPH09506164A (en) | 1997-06-17 |
| JP3252965B2 (en) | 2002-02-04 |
| WO1992022832A1 (en) | 1992-12-23 |
| DE69232203D1 (en) | 2001-12-20 |
| CA2111117A1 (en) | 1992-12-23 |
| EP0592515B1 (en) | 2001-11-14 |
| ATE208903T1 (en) | 2001-11-15 |
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