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Introducing MeasTools99^Ó for Windows
 MeasTools99^Ó is a full-featured coordinate measurement and analysis software application for use with Leica's TM-5000 series theodolites.  It runs under Windows^TM 95, 98 and NT.

Overview MeasTools99Ó (Measurement Tools) is a full-featured coordinate measurement and analysis software package for use with a Leica TDM-5000 series "total station" theodolite.  It runs under WindowsTM 95, 98 and NT.  Figure 1  shows some of the basic functionality of the software. In addition, MeasTools99 controls EMS' optional automated measurement system, allowing measurements of multiple targets to be made under full software control.

Some of the software highlights are described below.  The standard software features include:

Figure 1 MeasTools99 Plot Window (click on image to enlarge)

• manual measurement of an individual target
• inspection of reference points (comparison)
• search for current reference point inspection
• motor to selected point
• motor to next point in list
• fully automated measurement of multiple points
• optional eyepiece or on-screen video target sighting
• theodolite calibration utility
• creation of geometry features including line, plane, circle, cylinder, sphere
• intersections including point to line, point to plane, line to plane, 2 or 3 planes, etc.
• creation of multiple coordinate frames
• tabular and graphical data display (see Figure 1)

Measurement Modes

All theodolites measure vertical and horizontal angles.  EDM (Electronic Distance Measurement) "total station" instruments additionally measure distance, providing target location in spherical coordinates.  MeasTools99 downloads these data from the theodolite, converts them into Cartesian (XYZ) coordinates, and transforms them into the current coordinate frame if desired.  Additionally, MeasTools99 commands the theodolite to motor to specified target locations and takes measurements in the modes as shown in Figure 2 and described below: Manual Mode:  The users sets up  an "alpha" name and a numeric counter.  For example, the name might be "surface" and the counter may be set to 1.  Then for each manual measurement taken, the counter increments so that measured point names are "surface1", "surface2", etc.  The user may take a new manual measurement by using the mouse to left-click on an unused data line, right click on the data table or press the theodolite's measurement trigger. If the user left-clicks on an existing data line, the existing point is optionally overwritten.

Figure 2 Measurement Type

Inspect Mode:  If the user left-clicks on a data line with an existing reference point, a point is measured (or remeasured) and the difference between the measurement and reference point is shown.  If the "search" option is selected, the system searches the reference point list for a match within a user-specified acceptance window and displays the difference at that point.  In this way, a group of reference points can be measured in any desired order without the user knowing which point is currently under consideration.

Motor to Point:  The user may click on any reference or measured point and the system will motor to the selected location.  If "motor to next" is selected, the system will motor to a clicked point as above, and will automatically motor to the next selected point after a measurement is taken from the theodolite's trigger switch.

Full Automation:  The system will automatically motor to and measure a series of selected reference points.  If the automated system is installed and selected, the theodolite will home in on each point.
 

Geometric Features

The theodolite system measures points, which are the original geometry features.  Groups of features can be selected by and combined into a line, circle, plane, cylinder, sphere, point or distance as shown in Figure 3.  For instance, if a point and plane are selected, and a point is requested, the point on the plane by perpendicular projection is derived.  The figure shows the characteristics of a previously derived feature "A_CIRCLE".  Where applicable points are bestfit into the desired shapes, in this case a circle, and the fit RMS and residual errors are listed.

Special geometric features include:

Figure 3  Geometry Features Window (click on image to enlarge)

• the point projected onto a line or a plane
• the line projected onto a plane
• the intersection point of a line and a plane
• the intersection point of two lines
• the intersection line of two planes
• the intersection point of three planes

Coordinate Frames
Coordinate frames, also known as coordinate systems or frames of reference, involve rigid body geometric transformations of geometric features from one location in coordinate space to another.  This means that the relative relationships among these points, planes, lines, etc. remain unchanged even though they are all moved together to a new location.  This capability is necessary to work in the coordinate frame of the part being measured, whose origin and Cartesian coordinate axes will likely not be coincident with those of the theodolite system.
 

Any number of coordinate frames can be created, each of which can have parent and children relationships with others.  That is, each coordinate frame except the base (theodolite) system has a parent frame in which it was created, which in turn may have a parent frame, etc.  These histories are recorded by the software. There are 4 ways to create coordinate frames as shown in Figure 4: Fit Data Sets: Selected groups of measured and reference points can be bestfit with a 6 degree-of-freedom least squares algorithm, converting the measurements into the reference point coordinate frame.  The residual differences are shown in the "Diff" data columns. Build a Frame of Reference: A coordinate frame can be built by selecting the origin, one axis vector from among the vector features (line, circle, plane or cylinder) and a point on one of the remaining axes.  Axis directions can be reversed if desired.  All coordinate frames are right-handed Cartesian Manual Data Translation: The user can supply the 6 transformations required for a transformation to a new coordinate frame. Create Transform Matrix: The user can supply the same information in matrix format by inputting the 3x3 rotation matrix and the 1x3 translation matrix. The name of the new frame can be given, such as "PEDESTAL" in the figure.  The number in parentheses indicates the coordinate frame parentage.

Figure 4  Coordinate Frames

Calibration

The Leica TM-5000 series theodolites have build-in angle measurement calibration software.  MeasTools99 provides a distance measurement calibration routine which guides the user through the measurement of a reference bar of known length in order to determine the zero-offset value of the EDM (Electronic Distance Measurement) system.
	Figure 5  Theodolite Calibration Window (click on image to enlarge)

Automated Video System
Traditional theodolite use requires the operator to view a target through an optical eyepiece, where the eye is the sensing device.  EMS has developed a video eyepiece which optionally replaces the human eye with a CCD video camera in which the image is processed in the MeasTools99 software.  Figure 6 below shows three views of the system.  Figures 6a is a video image of a 1.5 inch diameter SMR (Spherically Mounted Retroreflector target) being viewed by the theodolite video system.  Figures 6b and 6c show front and rear views of the enhanced theodolite.  A cool fiber optic light source is used to provide good illumination of retroreflective targets, allowing operation at distances up to 100 meters.

Figure 6a  Video Theodolite System	Figure 6b  Video Theodolite Front View	Figure 6c  Video Theodolite Rear View
	(click on image to enlarge)

Figure 7 is shows the MeasTools99 video setup screen including the software crosshairs.  The theodolite is viewing a 20 mm square  tape retrotarget from a distance of 181 inches. During the video calibration process the software crosshairs is lined up with the theodolite internal reticle, and the video system pixels are mapped onto the theodolite's angle measurement system.
	Figure 7  MeasTools99 Video Setup Screen (click on image to enlarge)

MeasTools is designed for operation with the automated video sensor or the traditional optical eyepiece.