Introduction The kinematization solution aims to simplify the process of creating mechanisms using primitive geometries or convex geometries generated from 3D CAD models, without requiring the user to have a background in C#. It also enables the user to define the motion of each component.   All the new functionalities are available from the ribbon in the tab named Kinematization.   CAD Import You can import 3D CAD models by clicking on the CAD/Convex button. This will open a dialog window where you can select the CAD file to import. Currently, the supported formats are Collada (.dae), Standard Triangle Language (.stl), STEP (.stp, .step), CATIA (.CATPart, .CATProduct), and SolidWorks (.sldprt, .sldasm): Some remarks to be made about the import feature are: Imported CAD files will be serialized within the model. Every Assembly created through the CAD import is of type BodyAssembly. The performance can be affected by either a large number of geometries or the complexity given the mesh density.   When importing a Collada file, an additional window will appear, giving the user the option to split the 3D model into multiple parts. This allows the user to recreate the hierarchy specified in the file, resulting in the creation of multiple BodyAssembly objects in the scene.    gif also available as attached video "URrobotImportExample1"   Hierarchy Modification   Creation or modification of hierarchies can be performed using the following buttons:   Attach: This method creates a parent-child relationship between the selected assemblies. The first assembly selected will be defined as the parent. Detach: This method breaks the parent-child relationship. The selected assembly will be detached from its parent.   You can create a new empty Assembly by clicking on the Create button. This option allows you to create a blank Assembly that can serve as a container for building a new hierarchy.  gif also available as attached video "AttachDetach.mp4"   Convex Collider Geometry   In a scene, the parts are composed of two main elements: visual mesh and collider geometry. The visual mesh is what the user sees all the time, while the collider geometry is used by the PhysX engine to detect collisions and apply forces.   The BodyAssembly class has been modified to offer a more precise convex collider geometry that closely matches the visual mesh. This not only improves the fidelity of the collision detection but also speeds up the creation process.   Convex collider geometries are created through a process called Cooking. This process has been modified to make a second attempt if the PhysX engine fails during the Cooking process due to the complexity of the geometry or a large number of vertices provided. On the second attempt, the vertices will be quantized using K-means clustering, which reduces the number of vertices by creating an approximation of the original model. If the PhysX engine fails again during the second attempt, a box collider geometry will be created.   Body Assembly The BodyAssembly class has been specifically developed to work with the Kinematization solution. The following points describe the key characteristics and behaviors provided by the class.   It provides polymorphism, allowing you to change its geometry to a primitive shape (box, cylinder, and sphere) or a convex shape (CAD file models). The behavior of the Body can vary depending on the selected dynamics Bodiless: It is kinematic and has no collider Rigid: It is kinematic and has a collider Physics: It is dynamic, and its position and velocity are determined by the forces acting on it.   Minimum position and velocity iterations improves the results of the PhysX engine solver for the current Body, when using physics joints. Collision allows you to enable or disable collision with other BodyAssembly objects in the scene, without destroying the collider.   Gravity allows you to enable or disable the effect of gravity on the current Body   Weight defines the density of the Body considering its volume   Motion Body Assembly has been designed to be compatible with Kinematic Axis Assembly and Physics Joints. On the other hand, you can perform combination between Kinematic Axis and Physics Joints to create mechanisms.   gif also available as attached video "SliderCrank.mp4" Kinematic Axis It allows for the movement of single or multiple assemblies that have been attached to it. It supports the attachment of Kinematic Axis assemblies to create serial or parallel kinematic chains. It supports the attachment of Body Assembly objects which belong to a structure composed by joints and which Dynamics type is Rigid. It provides only one degree of freedom. To simplify the motion assignment process, the user can select an assembly either from the scene or Solution Explorer and click on “Kinematic Axis”. This action will create a Kinematic Axis in the scene as the parent of the selected assembly, maintaining the same position and orientation. The same results can be achieved by selecting multiple assemblies before creating the Kinematic Axis. If no assembly is selected, a single Kinematic Axis will be added to the scene.   The motion of the Kinematic Axis can be defined based on the drive type. By default, you have the option to use Position, Velocity, or Forward and Backward drives. If you need to use a custom drive, select the option Custom. Any class that inherits from the Electric or Positioner class will be added and displayed in the Custom Drive property. Simple Motion Serial Kinematic Chain Kinematic Axis and Physics Joints   Passive Physics Joints A physics joint requires two BodyAssembly objects, and it defines the way bodies move relative to one another. The provided physics joint is of type D6 which is a highly configurable joint. It allows for the specification of individual degrees of freedom to either move freely or be locked.   Joints can only be created through the Joint Editor Window, and are compatible only with BodyAssembly types. On the other hand, bodies cannot be Bodiless since the PhysX engine requires the collider geometries of the bodies.   The Joint Editor Window allows the user to perform a quick configuration of the joint by enabling/disabling the degree of freedom. However, to get access to the full configuration of the joint, select the Physics Joint object in the Joint Editor Window, and the properties will be displayed in the Properties Window.   The joint position and orientation are relative to the BodyAssembly, which has been set as the origin. The child position and orientation are relative to the joint origin. Besides, it is possible to change the geometry type even if the BodyAssembly is already connected to a physics joint. Experior automatically will reconstruct the joints connected to the body.   No collision is presented between the BodyAssembly objects that are linked through the same physics joint. However, collision is present with external BodyAssembly objects or any other Assembly in the scene which has rigid parts.    Attachment of Assembly objects to BodyAssembly which already belong to a physics joint, is allowed. Nevertheless, the objects attached will not impact nor modify the motion of the joint since attached objects mimic the change of position and orientation. Active Physics Joints Example Physics Joints Pose Physics Joint Reconstruction Physics Joint with Attachment   URDF Import When importing the Universal Robot Format (URDF) file, multiple Body and Kinematic Axis assemblies will be created based on the information specified in the file. Joints specified by URDF are constructed using Kinematic Axis assemblies. Unlike CAD import, URDF import allows to have BodyAssembly objects with custom colliders, regardless of the visual mesh geometry. This is possible if the collider information is provided by the URDF file.   NOTE: URDF import supports the same CAD formats mentioned for CAD import (.dae and .stl) To maintain the specified hierarchy in the file, parent, joints, and child relations are kept. When using Kinematic Axis assemblies as joints, the configuration applied to them based on the content of the file includes three aspects: Type, Axis, and Limits.   Physics Joints Tips / Suggestions The following tips and suggestions are provided to improve the response of the PhysX engine and to have a more stable mechanism composed by passive physics joints. Mass ratios above 10 are to be avoided, as the solver is not designed for high rigidity systems. The bodies with higher mass will dominate the movement. Setting the mass of the parts to the real value might not be the best way to set the parameter, depending on the mass ratios. Setting a realistic center of masses can be useful to providing higher stability to a mechanism, as it will greatly influence how the joint affects the angular movement of the body. The higher the solver iterations, the more “rigid” the joint will be (less flexible). Position iterations will mainly provide the accuracy of slow-moving mechanisms. Velocity iterations will improve the accuracy of high-speed movement. Law of diminishing return applies for the last two points. In some scenarios, gravity and collision could be disabled to improve the accuracy of the simulation, in the case that these interactions are not required for the specific simulation that is being done. Wrong Parameters     Parametrized   More demos can be find attached as Deltapicker-demo.mp4 and T-robot-demo.mp4

On occasion, it can be useful to launch Experior with certain startup options to change the program’s functionality.   This article lists each command line argument, that you can use when launching Experior.   You can also view a list of these startup options by using the -help or -? command line argument when launching Experior.   Inputting the argument Command line (cmd) Open a command prompt (cmd.exe) Write path to your install directory, by default: “C:\Xcelgo\Xcelgo Experior 7\Experior.exe”  Append the argument and press enter (How it would look with default directory: “C:\Xcelgo\Xcelgo Experior 7\Experior.exe” -help)   Shortcut Right click the shortcut you use to launch Experior Click on Properties Go to the Shortcut tab In the field labelled Target:, append the text with your argument Click Apply and Ok Here is an example with the -help argument:     Visual Studio Right click the project that launches Experior Click on Properties Go to the Debug tab Go to Start options > Command line arguments Type in your argument Save (ctrl+s) Here is an example, once again using the -help argument:     Full list of startup options -help|-? Opens a command prompt with a list of all command line arguments available for the current Experior version.   -startupconfiguration <filepath> or new Specify a startup configuration file to use. You can read more about this here.   -config Displays the ‘Catalog Selector’ dialog during startup.   -headless Starts Experior in headless mode. NOTE: this will also enable webapi and graphicsserver   -webapi [off|filepath] Enable webapi or [off] to disable it or enable webapi and specify the webapi configuration file to use.   -graphicsserver [off] Enable graphics server or [off] to disable graphics server.   -model|-modelfile <filepath> Experior opens a model if the argument matches the name of an existing Experior model.   -phy|-physics Starts Experior in physics mode. (Only functional with the right privileges)   -variable Using variable time steps (physics mode). (Default: Experior is using fixed time step method)   frictiontype <Patch|OneDirectional|TwoDirectional> Starts the physics engine with the chosen friction type (only available in Physics mode). (Default: Experior is using Patch mode)   -physicsenginedynamics <Classic | Advanced> Enables advanced dynamics of loads which provides a more realistic motion of loads produced by conveyors and stacks stability (only available in Physics mode). (Default: Experior is using Classic dynamics)   -des|-event|-events Starts Experior in discrete Events mode. (Only functional with the right privileges)   -eng|-engineering Starts Experior in engineering mode. (Only functional with the right privileges)   -builder Starts Experior using ‘Builder’ profile. (Only functional with the right privileges)   -commissioner Starts Experior using ‘Commissioner’ profile. (Only functional with the right privileges)   -tester Starts Experior using ‘Tester’ profile. (Only functional with the right privileges)   -viewer Starts Experior using ‘Viewer’ profile.   -oem Start Experior in OEM licence mode. See OEM Setup (link)   -license <filepath|dongle[:id]>|offline[:id]> Specify either a specific license type to use (dongle, offline, or weblicensefile) or specific license (dongle:id). (example: -license C:\Experior\license.key) (example: -license dongle:xxxx)   -licenseusage <id> Set the licenseusage property for web license usage tracking.   -forcecheckin Check-in web license when Experior closes without asking user.   -libs <directory> Set an additional libraries directory. (example: -libs C:\Projects\Demo\)   -logfilemode <none|file|filedate|filemodelname> Set the log file mode. (example: -logfilemode file)   -log <filepath> Set a temporary log directory. (example: -log C:\Experior\Logs\)   -workdir <directory> Set working directory (permanently). NOTE: this argument will not work in combination with another argument. The application will not be started – only the directory will be set. (example: -workdir C:\Experior\)   -debug [none|debug|detailed] Enable debug level ‘Debug’ or optionally set debug level to specified level.   -reset Reset the Working directory and reset configuration files to default settings.   Automated Testing -continuous Keep discrete event engine running.   -autostart Run the model when it is loaded.   -stopafter <duration> Stop the model and close Experior after a period of time – ‘duration’ defines the time in seconds before the model stops and Experior starts closing.   -atstart <sym/name> Here you provide a symbol name or assembly name that should be activated when a model is started (after connections are established) so that this can initiate some action in the model.   -timescale <scale> Specify the time scale to use. (example: -timescale 2.5)   -seed <seed> The seed used by the random generator.   -eventfile <filepath> Loads an event file (*.events). (this is only possible when a model file is loaded at the same time)

The measurement handler is an extension on the Kinematization feautre. It provides a way for the user to have access to different measurements related to assemblies from the Kinematization plugin. These are the main functionalities:    The user can add different measurements to Kinematization Assemblies. Body assemblies support pose related measurements, and kinematic axis assemblies support pose and scalar measurement.  Measurements can be monitored through a real-time plot.  Measurements can provide feedback to a PLC.  Measurements can be exported to a CSV file.  Currently, the user interacts with this feature through the context menu. These are the main actions the user may take:    Enable Measurement Handler To be able to use this feature with a specific assembly, the Measurement Handler must be enabled.  Open the context menu and expand the Measurement Handler menu.  Click on Enable Measurements    Add a Measurement Once the Measurement Handler is enabled, the user can add measurements. To add pose measurements (only IPoseMeasurables):  Open the context menu and expand the Measurement Handler menu.  Expand Measurements, expand Add New Measurement Relative to. Here you can see the Global coordinate system, as well as all other assemblies that implement the IPoseMeasureable interface and have their Measurement Handler enabled. This will be the reference point for the measurements that will be added.  Once you select the reference point of the measurement, a selection window will appear. Here the user can select what measurands should be added.  Click OK.  To add scalar measurements (only IScalarMeasurables):  Open the context menu and expand the Measurement Handler menu.  Expand Measurements, expand Add New Scalar Measurement to. Here you can see the name of the measurand that can be added. Select the desired measurand.    Connect Feedback to PLC Once the measurements have been added, the Feedback signals will be visible from the solution explorer. Here the user can select the signal and assign the Connection ID and path through the property window (as a normal PLC Input).      Plotting a Measurement Once the measurement has been added, a real time view of the measurement can be plotted. The user must:  Open the context menu and expand the Measurement Handler menu.  Expand Measurements, Existing Measurements, and look for the measurement that must be plotted. Expand this menu.  Click on Plot.  The plot window will open. It will update while the model is running.        Exporting Measurements The measurements can be exported to a CSV file. This is only possible if measurements have been recorded in the model, and the scene is paused.    Open the context menu and expand the Measurement Handler menu.  Select Export Multiple Measurements.  The Multi Measurand Exporter window will open. Here the user may select as many measurands they would like to export. Additionally, they can select if they want to have the measurements with respect to time, or another measurement.  Once the selection is completed, click on Export.  Select the output path for the file. 

The Logic Configurator is accessible as a view within in Experior 7s user interface. It allows you to configure logical relations between the elements of the scene in a graphical editor. You can use the Logic Configurator to create flow simulations by adding logical operations and connecting them with elements of the scene. The Logic Configurator provides element inputs and outputs and allows you to configure the relations between them without a controller.   See the attached video Logic-Configurator-demo.mp4 for a quick demo.   Creating Connections To establish a relation between blocks, follow these steps:   Click an output of one assembly block. Hold down the left mouse button and draw a connecting line to the input of another assembly block. The connection between two blocks is indicated by a solid line. Connections can only be established between inputs and outputs of the same type. To remove a connection, follow these steps:   Right-click the connection in the Logic Configurator. Click Delete from the contextual menu.   NOTE: Each input can be connected to only one signal, whereas each output signal can have multiple connections   Good Practices Accessing the Commands You can access the contextual menu commands by typing the first letter of the command.   Examples: Right-click in the Logic Configurator view to open the contextual menu and type: t  to create a Timer block. c  +  c  to create a Counter block because this is the second command in the list starting with  c . m  +  n  to create a Number block. It serves as a shortcut to use the command Mathematics  >  Number.   Creating Multiple Blocks for the Same Assembly To create a clear arrangement of blocks and connecting lines for the same assembly or motor, you can use multiple blocks. To achieve this:   Select the assembly or motor in the scene. Right-click anywhere in the Logic Configurator view and click Create Register Node(s) several times until the desired number of blocks is created.   NOTE: If you create multiple instances of the same assembly or motor and you establish multiple connections to the same input, the block uses the last updated input value as the default input.   Example: To establish clear visibility of connecting lines when representing an output signal located on the right-hand side of the assembly block (Basic Surface Motor 1 in this example) connecting to another block located on the left-hand side (Timer in this example), it is a good practice to create an additional instance of the block (Basic Surface Motor 1 in this example) and position it on the left-hand side (of the Timer block in this example).   Creating Multiple Blocks for the Same Assembly To create a clear arrangement of blocks and connecting lines for the same assembly or motor, you can use multiple blocks. To achieve this:   Select the assembly or motor in the scene. Right-click anywhere in the Logic Configurator view and click Create Register Node(s) several times until the desired number of blocks is created. NOTE: If you create multiple instances of the same assembly or motor and you establish multiple connections to the same input, the block uses the last updated input value as the default input.   Example: To establish clear visibility of connecting lines when representing an output signal located on the right-hand side of the assembly block (Basic Surface Motor 1 in this example) connecting to another block located on the left-hand side (Timer in this example), it is a good practice to create an additional instance of the block (Basic Surface Motor 1 in this example) and position it on the left-hand side (of the Timer block in this example).   Displaying Boolean and Numerical Values   The values of Boolean and numerical inputs and outputs are, by default, not displayed for all blocks in the Logic Configurator. To make these values visible, create the following blocks and connect them to the inputs or outputs:   Boolean Display blocks to visualize Boolean outputs. Number Display blocks to visualize numerical outputs.   Managing Blocks To create blocks, right-click in the Logic Configurator and select a command from the contextual menu to create a specific block.   To remove a block, right-click the block and use the Delete command from the contextual menu or select the block and press the Delete key on your keyboard.   Configuring Blocks You can configure a block in two different ways:   Select the block in the Logic Configurator and configure the corresponding parameters in the Properties view on the right-hand side of the Experior window. Create other blocks, for example, Mathematics blocks, and establish relations between the blocks within the Logic Configurator.

The Startup configuration file is used to launch experior with a set of predefined options.   In order to generate this file, you first start Experior with the command line argument -startupconfiguration new   This will create the file “StartupSettings.json” in the install directory folder, which as standard is set to: C:\Xcelgo\Xcelgo Experior 7   You can now navigate to the folder and edit this file with a text editor.   To make use of the settings, start experior with the command line argument -startupconfiguration (filepath)   Note: Remember to include the filename and extension in the filepath. Referencing the directory is not enough.   The command line arguments have a higher priority than the configuration file options. This means, that an option set in both the configuration file and the command line, will use the command line argument.   The options in the configuration file that are available as command line arguments are listed in the “Startup options” article.   The data is formatted in JSON and the file looks like this:   { "Config": false, "Headless": false, "DebugLevel": "None", "LogMode": "FileDate", "LogDir": null, "WorkDir": null, "SelectedEngine": "Events", "PhysicsFrictionType": null, "TimeScale": 1.0, "ContinuouslyRunning": false, "Seed": 0, "OEM": false, "WebApiEnabled": false, "GraphicsServerEnabled": true, "ModelToLoad": "C:\\Projects\\ExampleProject\\Models\\ExampleModel.Experior", "AutoStart": false, "StopAfterSec": 0, "AtStart": "", "EventFile": "", "LicenseSource": "", "LicenseUsage": "", "ImpersonateProfile": "None", "ForceCheckIn": false, "FingerprintReport": false, "SelectedCatalogs": [ "Experior.Catalog.Training.dll", "Experior.Catalog.ExampleCompany.Conveyors.dll", "Experior.Catalog.ExampleCompany.Feeders.dll", "Experior.Catalog.Xcelgo.GuidedPath.dll", "Experior.GuidedPath.Base.dll", "Experior.Catalog.Xcelgo.Buildings.dll" ], "SelectedExternalLibsPath": "", "ExternalLibsPaths": [], "BetaFeaturesEnabled": false, "ValidateSerialization": false, "LicenseServerFallback": false, "WebApiConfigurationFilePath": "" }   Config: Option type: boolean (true or false). Description: true will force a display of the ‘Catalog selector’ during startup, false will only display the dialog in case an input is needed. Default: false.   Headless: Option type: boolean (true or false). Description: true will start Experior in ‘headless’ mode (i.e. console mode with no UI other than console input/output), false will start Experior in UI/IDE mode. Default: false.   “DebugLevel”: Option type: string (“None”, “Debug” or “Detailed”). Description: Set the desired debug level. Default: “None”.   “LogMode”: Option type: string (“None”, “File”, “FileDate” or “FileModelName”). Description: Set the desired log file mode. Default: “None”.   “LogDir”: Option type: filepath string (null, empty or a valid directory path). Description: Set the desired log file directory path. Default: null (will result in debug.log in %localappdata%\Xcelgo\Experior\7\Work\Logs\debug.log).   “WorkDir”: Option type: filepath string (null, empty or a valid working directory path). Description: Set the desired work directory path. Default: null (will result in workdir being %localappdata%\Xcelgo\Experior\7\Work\).   “SelectedEngine”: Option type: string (“Physics”, “Events” or “Engineering”). Description: Set the desired engine type. (Only functional with the right license privileges). Default: “Physics” if several engines allowed otherwise the single allowed engine.   “PhysicsFrictionType”:  Option type: string (null, empty, “Patch”, “OneDirectional” or “TwoDirectional”). Description: Starts the physics engine with the chosen friction type (only available in Physics mode). Default: “Patch”.   “PhysicsEngineDynamics”:  Option type: string (null, empty, “Classic” or “Advanced”). Description: Enables advanced dynamics of loads which provides a more realistic motion of loads produced by conveyors and stacks stability (only available in Physics mode). Default: “Classic”.   “TimeScale”:  Option type: floating point value (positive). Description: Specify the time scale to use. Default: 1.0. Example: 2.5   “ContinuouslyRunning”: Option type: boolean (true or false). Description: Prevents the model from stopping automatically when certain situations occur. (Example: In “Events” engine mode, the last load in the scene is deleted.) (Only applied in case of an applicable engine type) Default: false.   “Seed”:  Option type: integer. Description: The seed used by the random generator. Default: 0.   “OEM”:  Option type: boolean (true or false). Description: Start Experior in OEM licence mode. See OEM Setup (coming soon) Default: false.   “WebApiEnabled”:  Option type: boolean (true or false). Description: Enable or disable WEB API. Default: true if headless is true, otherwise false.   “GraphicsServerEnabled”: Option type: boolean (true or false). Description: Enable or disable Graphics Server. Default: true if headless is true, otherwise false.   “ModelToLoad”: Option type: filepath string (null, empty or valid filepath). Description: Set the desired model file to load after startup. (example: “C:\\Projects\\ExampleProject\\Models\\ExampleModel.Experior”) Default: null   “AutoStart”:  Option type: boolean (true or false). Description: Run the model when it is loaded. Default: false   “StopAfterSec”:  Option type: integer. Description: Stop the model and close Experior after a period of time – ‘duration’ defines the time in seconds before the model stops and Experior starts closing. Default: 0   “AtStart”:  Option type: string (null, empty or valid symbol or assembly name). Description: Here you provide a symbol name or assembly name that should be activated when a model is started (after connections are established) so that this can initiate some action in the model. Default: empty   “EventFile”:  Option type: filepath string (null, empty or valid filepath). Description: Loads an event file (*.events). (this is only possible when a model file is loaded at the same time) Default: empty   “LicenseSource”:  Option type: string (null, empty or valid filepath). Description: Specify either a specific license type to use (dongle, offline, or weblicensefile) or specific license (dongle:id). (example: -license C:\Experior\license.key) (example: -license dongle:xxxx) Default: empty   “LicenseUsage”:  Option type: string (null, empty or any string with maximum length of 50 characters). Description: Set the licenseusage property for web license usage tracking. Default: empty   “ImpersonateProfile”: Option type: string (“None”, “Viewer”, “Tester”, “Commissioner” or “Builder”). Description: Start Experior at a lower license level than the one you have access to. (See: Types of Licenses ) Default: “None”   “ForceCheckIn”: Option type: boolean (true or false). Description: Check-in web license when Experior closes without asking user. Default: false   “FingerprintReport”: Option type: boolean (true or false). Description: For License debugging, appends a log file with a timestamp and license information. Default: false   “SelectedCatalogs”: Option type: array of strings (null, empty or an array of valid filenames). Description: A list of catalog dll filenames for catalogs that should be loaded when Experior starts. Default: empty   “SelectedExternalLibsPath”: Option type: directory path string (null, empty or a valid directory path). Description: A path to any libraries (dll’s) not within the Experior installation folder, that Experior should reference on startup. Any catalog dll’s contained within this folder will appear in the catalog selection window, when starting Experior. Default: empty   “ExternalLibsPaths”: Option type: array of directory path strings (null, empty or an array of valid directory paths). Description: Any other paths to catalog dll’s can be set here, these paths will be selectable in the dropdown of the catalog selector window, when starting Experior. Default: empty   “BetaFeaturesEnabled”: Option type: boolean (true or false). Description: Certain experimental features can be enabled with this set to true. Default: false   “ValidateSerialization”: Option type: boolean (true or false). Description: Validates loaded catalogs to make sure there are no issues with serialization (saving/loading). This is useful for debugging catalogs, as you dont need to load a model or create assemblies in the scene to trigger an error. Default: false   Example: If 2 catalogs have an assembly infoclass that uses the same xml typename, Experior won’t know which one to load.   “LicenseServerFallback”: Option type: boolean (true or false). Deprecated (no longer used) Default: false   “WebApiConfigurationFilePath”: Option type: filepath string (null, empty or a valid filepath). Description: The webapi configuration file. See: “Startup Options” article -webapi Default: empty (will result in default values)   “CoordinateSystem”: (optional) Option type:  string (“LeftHanded” or “RightHanded”). Description: Determines whether Experior should use a Righthanded or Lefthanded coordinate system. Default: “LeftHanded”