Remote sensing for resources development and environmental management: Remote sensing for resources development and environmental management

Damen, M. C. J.

Bibliographic data

Multivolume work

Persistent identifier:: 856342815

Title:: Remote sensing for resources development and environmental management

Sub title:: proceedings of the 7th international Symposium, Enschede, 25 - 29 August 1986

Year of publication:: 1986

Place of publication:: Rotterdam; Boston

Publisher of the original:: A. A. Balkema

Identifier (digital):: 856342815

Language:: English

Additional Notes:: Volume 1-3 erschienen von 1986-1988

Editor:: Damen, M. C. J.

Document type:: Multivolume work

Volume

Persistent identifier:: 856343064

Title:: Remote sensing for resources development and environmental management

Sub title:: proceedings of the 7th international Symposium, Enschede, 25 - 29 August 1986

Scope:: XV, 547 Seiten

Year of publication:: 1986

Place of publication:: Rotterdam; Boston

Publisher of the original:: A. A. Balkema

Identifier (digital):: 856343064

Illustration:: Illustrationen, Diagramme

Signature of the source:: ZS 312(26,7,1)

Language:: English

Usage licence:: Attribution 4.0 International (CC BY 4.0)

Editor:: Damen, M. C. J.

Publisher of the digital copy:: Technische Informationsbibliothek Hannover

Place of publication of the digital copy:: Hannover

Year of publication of the original:: 2016

Document type:: Volume

Collection:: Earth sciences

Chapter

Title:: 1 Visible and infrared data. Chairman: F. Quiel, Liaison: N J. Mulder

Document type:: Multivolume work

Structure type:: Chapter

Chapter

Title:: Thematic mapping and data analysis for resource management using the Stereo ZTS VM. Kurt H. Kreckel & George J. Jaynes

Document type:: Multivolume work

Structure type:: Chapter

4 Parallax Bar with Floating Mark The VM operation is based on the floating mark prin ciple using an automated parallax bar. The floating marks are illuminated dots of 75, 125, 250 or 500 /im diameter on plastic disks in direct contact with the photographs (separated by a 7 mil thick Mylar protective marked cover). This approach emphasizes the measurement on the photograph. Height measure ment is direct and not subject to distortions. Most of the time the photographs are in superimposition with the map. However, to achieve optimal height measurement accuracy it is possible to increase the photomagnification beyond that required for super imposition. The parallax bar is motor driven in the X and Y directions. X and Y parallax separations (px and py respectively) are also motor driven using a single 4 dimensional joystick control. All four axes are encoded: X and Y by rotary encoders with 50 /urn re solution, py by rotary encoder with 5 jam resolution, and px by a linear incremental encoder of 5 /am reso lution to eliminate any backlash or linear to rotary conversion errors. Assuming a nominal photobase of 100 mm the theoretical system resolution of measured height is .005% of the flying height. With this inherent capability of the instrument it is up to the experience and training of the operator to achieve repeatability and accuracy as near to the theoretical as possible (Trinder, 1986). Relative and absolute orientation parameters are automatically converted into correcting motions of the px and py stepper motor drives to eliminate y parallax anywhere in the overlap area of the photo graphs and to provide automatic height and elevation correction for the various tilts and displacements inherent in near vertical photography 5 VM Computer and Display Computations of orientation parameters, correction values for the motors, height and elevation measure ments are performed by an Intel 8031 (8051 family) microprocessor based system with approximately 45 kBytes of ROM based program memory. Programming was done in Assembler language to achieve a maximum data transfer rate from feedback elements to computing and to the motor drives of px and py parallax motions. The computer is housed in a control unit shared by power supplies, encoding, joystick and motor control circuitry. A separate Keyboard/Display unit is posi tioned to the side of the operator (Fig. 2). It dis plays at all times the photo X and Y coordinates and a selected value or parameter (normally height or elevation). The keyboard allows keying-in of parameters, offsets, units, etc. Figure 2. VM Keyboard/Display Unit 6 VM Output Capability (Printing) Many users performing simple land use studies re quiring the measurement of spot and object heights may need no more than just a display of such heights together with the corresponding X/Y photocoordinates to be able to reconstruct the setup and repeat the measurements. Other workers require a hard copy of the jobs per formed. For this purpose an 1/0 capability with a dot matrix printer has been provided which on command (pushbutton on the joystick assembly, Fig. 3) will transfer a selectable and sequentially incrementing observation number, height, elevation, and photo X/Y coordinates to a printer for a permanent record. Selecting another transfer mode allows a permanent record of relative, absolute orientation parameters and X, Y, Z control point photo-and ground coordinates. Switches on the VM 1/0 board permit adapting the printer output to a variety of popular printers. Figure 3. VM Joystick Assembly with Transfer Buttons 7 VM Input/Output Capability (Computer Interface) Via another output port, an RS 232 type serial 1/0 port, calibration parameters and running observation numbers, height, elevation, X/Y photocoordinates may be transferred to an external personal, micro-, mini computer with its own RS 232 interface. Three push buttons are provided on the joystick assembly to initiate the transfer and to distinguish between con tinuous, interrupted and termination of transfer. The baud rate may be selected on DIP switches on the VM 1/0 board and usually on DIP switches of computer serial 1/0 boards. Alternatively computers may have a software baud rate selection capability. The availability of 300 and 1200 Baud selections enables transfer of data via a standard modem. The VM is normally connected as Data Terminal Equipment (DTE). Conversion to Data Communication Equipment (DCE) may be done by plug inversion on the VM 1/0 board. The transfer of calibration and coordinate data to Bausch & Lomb's own Resource Measurement System (RMS) has been implemented. The data transfer rate is as high as 9600 Baud at distances between VM and computer of up to 30 m. Transfer to an IBM PC/AT computer is also being undertaken. Data have been structured into blocks of ASCII data and symbols according to a logical compact data format. The data structure is available to anyone wishing to interface to his own computer. 8 VM - RMS Data Transfer The RMS system uses a built-in Apple lie computer. Operator friendly menu based software has been im plemented to set up the RMS to receive either cali bration data or coordinate data from the VM and to store the data in files designated as "filename.cal" or "filenam Such disk t as many as data are av sion, analy ing to menu 9 Data Edit The stored ASCII forma readable an coordinate Typically n due to nois operator er in this eff or profile RMS CRT for Transferr dinates whi coordinates taining the absolute or known princ (Manual of Data anal and perimet ear feature Internal of RMS anal (mean, vari linear, mul logarithmic ANOVA, etc. 10 Data Pri The data co ed out on t relating ob values with The RMS pro generated b of graphs. 11 Data Plo Planimetric coordinate) or elevatio Y*Y) profil (DMP 40 or sets. The information at the time made on eit overlays us type plot m relative to ersed by a : 12 Conclusi The combina Bausch & Lo measurement as measurem photograph of a printe powerful sy low capital maintenance is in high rather than with the Re RMS routine 38

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