The Graphical Simulation application is an information visualization tool used to display information about the vehicle systems used at the Space Systems Laboratory. This program is part of a package which allows users to perform several tasks: train robotic operators prior to system testing, demonstrate capabilities by simulating robotic operations, visualize actual vehicle telemetry, or test changes to a robotic system in simulation before modifying the actual vehicle.

The graphical simulation is merely an visual output for data. It allows for the positioning of infinite camera viewpoints, including cameras attached to vehicles and manipulators. Stereo viewing is capable using either StereoGraphics CrystalEyes or a head mounted display. Using a series of buttons and switches objects can be added, hidden, and moved. Also objects state can be change, allowing for transparency and color modifications to occur. The following manual describes the different windows of the graphical simulation and how to control the features of this application.

1. View Control Window

The View Control Window controls all of the graphics windows in the simulation. Up to four graphics windows can be displayed, including a split stereo window. Each window's viewpoint can be chosen and controlled.

   
 Figure 1: View Control Window  Figure 2: View Selection Menu

 
Figure 3: Message Type Selection Menu  Figure 4: Input Device Selection Menu


1- Graphics Window Control Selectors

These radio buttons switches which graphics window is changed with the controls on the bottom of the window.

2- View Selection Option Menus

This menu, Figure 2, allocates the camera viewpoint for the appropriate graphics window. Using the None menu item closes that graphics window. Up to four camera viewpoints can be displayed at one time. This includes a split stereo window with side-by-side left/right eye viewpoints.

The camera view and message selection combined designate the exact view being controlled. Therefore a camera attached to the actual position of Ranger could be manipulated. The cameras attached to the desired, commanded and trajectory position for Ranger would remain unaffected. All other views would also be unaffected.

3- Message Type Radio Buttons

These menus, Figure 3, are used to select which message type is coupled with the camera view. The follwoing selections are available:

Act - Actual Position
Cmd - Command Positon
Des - Desired Position
Traj - Trajectory Position

The camera view and message selection combined designate the exact view being controlled. Therefore a camera attached to the actual position of Ranger could be manipulated. The cameras attached to the desired, commanded and trajectory position for Ranger would remain unaffected. All other view would also be unaffected.

4- Interlace Stereo Button

This button is not functional yet. It take the graphics window designated by the Graphics Window Control Selectors and creates a full screen interlace stereo image which can be used with CrystalEyes LCD glasses. Hitting the Escape key will disable the stereo view.

5- Field of View Controls

The field of view (FOV) for the specified graphic window can be changed. This gives the effect of zooming in or using a wide-angle lens. The input field can be used to directly change the horizontal FOV in degrees. The up and down arrows will increment/decrement the current FOV angle. Each mouse button has a different increment/decrement value.

Left mouse button = ± 10 degrees
Middle mouse button = ± 5 degrees
Right mouse button = ± 1 degree

6- Viewpoint Control Input Option Menu

This menu allows the user to choose which input device, Figure 4, can be used to move the camera viewpoint. This is only an offset from the tracked position. For instance, if the View Selection Option Menu designates the viewpoint as Ranger, the camera viewpoint is at the bore sight camera. Using the designated input device this viewpoint can be move to an over the shoulder view, trailing view, or rear view. The camera is still attached to Ranger, but is offset.

7- Input Device Multiplier Control

This input field allows the multiplier for the input device to be changed. Therefore the hand controller can become more or less sensitive. For Cartesian position devices (6DOF Trackers), only the translation components are multiplied. The rotation remains at x1 multiplier.

8- Viewpoint Manual Control

These buttons and input fields can be used to move the camera offset to any position. This is useful when there are a few fixed viewpoints, which are useful. The input fields can be used to directly move to a location. The translational inputs are in units of meters, rotational inputs in degrees. These input fields are automatically updated when an input device is used. Therefore, the input device can move the viewpoint, and then that viewpoint could be recorded and used later by typing those values in later.

The buttons can be used to increment/decrement the current location depending on which mouse button is used.

Left mouse button = ± 10 degrees
Middle mouse button = ± 5 degrees
Right mouse button = ± 1 degree

These changes are in the camera frame of reference, so hitting the up forward button will always move the camera toward its view.

9- Viewpoint Initialization Button

This button returns the viewpoint to its original position. It removes the offsets induced by the input device and manual control.

2. Display Control Window

This window controls which objects are displayed in the graphical simulation. All the Space Systems Laboratory's vehicles and the Research Facility itself can be displayed.

   
 Figure 5: Display Control Window  Figure 6: Display Selection Menu


1- Neutral Buoyancy Lab Display Selection Menus

These option menus, Figure 6, change the state of the Neutral Buoyancy Research Facility structures. The NBRF tank and underwater mock-up of the space lab pallet can be changed. The menu allows for one of three states.

None - removes the object from the display completely.
Opaque - displays the object in solid form.
Virtual - displays the object as translucent which is see-through

2- Vehicle Display Selection Menus

These option menus, Figure 6, change the state of different vehicles in the Space System Laboratory. SCAMP, SCAMP Space Simulator Vehicle, and Ranger can be displayed independently. Ranger EM (Electronics Module) will be used on Ranger TSX. Ranger PM (Propulsion Module) is added with the EM to complete the Ranger Neutral Buoyancy Vehicle. The menu allows for one of three states.

None - removes the object from the display completely.
Opaque - displays the object in solid form.
Virtual - displays the object as translucent which is see-through

The vehicles are displayed using specific telemetry data. The Actual data is the current location the vehicle. Commanded data is where the vehicle is told were to go by the control station. Desired data is where the vehicle is trying to go. And the Trajectory data is output by the trajectory planner program to create an optimal path for the vehicle to move.

3. Arm Display Control Window

This window controls how Ranger's manipulators are displayed in the graphical simulation.


   
 Figure 7: Arm Display Control Window  Figure 8: End Effector Menu

 
 Figure 9: Display Selection Menu

1- End Effector Selection Menus

These menus, Figure 8, switch out which end effector is each arm.

2- Ranger Arm Display Menus

These option menus, Figure 9, change the state of different arms on the Ranger vehicle.

DXL - 7DOF Left Dexterous Arm
DXR - 7DOF Right Dexterous Arm
GRP - Grapple Arm
VID - Video Arm
DXL8 - 8DOF Left Dexterous Arm
DXR8 - 8DOF Right Dexterous Arm

The menu allows for one of three states.

None - removes the object from the display completely.
Opaque - displays the object in solid form.
Virtual - displays the object as translucent which is see-through

The vehicles are displayed using specific telemetry data. The Actual data is the current location the arm. Commanded data is where the arm is told were to go by the control station. Desired data is where the arm is trying to go. The Trajectory data is output by the trajectory planner program to create an optimal path for the arm to move.

4. Graphical Summary Window

This window is used to control many of the objects in the graphical simulation. Several input devices can be used to move vehicles, cameras, and external viewpoints.


 
 Figure 10: Graphical Summary Window  Window Figure 11: Object Menu
 
 Figure 12: Message Type Menu  Window Figure 13: Input Device Menu

1- Camera Offset Input Menus

These menus, Figure 13, allow the user to select which input device will be used to offset the current view. This was designed so that the use of a head tracker could be used with another input device, like hand controllers. This allows the head tracker to move an offset away from the object's position, without moving that offset.

2- NDDS to Shared Memory Activation Button

This button initiates and terminates the process, which converts NDDS messages to Shared Memory. It is need to visualize actual Ranger telemetry or dynamic simulation data.

3- Offset Mode Toggle

This toggle button switches between to offset modes. This is how the Camera Offset Input is used. In tracking mode, the device is similar to conventional head tracking. In target mode, the object is always kept in the center of the viewing area. Therefore if a Ranger viewpoint is used, target mode will keep the center of Ranger in the same location. Although difficult to explain, experimenting can show how this mode could be useful.

4- Input Device Multipliers

These input fields multiply the translational and rotational components coming from the respective input devices. Again for Cartesian position devices only translation is multiplied, rotation remains at x1.

5- Simulation Control Input Menus

These menus, Figure 13, allow the operator to use any of the approved SSL input devices to control the different objects withing the simulation. North and South Porthole cameras are fixed, therefore only pitch, yaw, and zooming are allowed.

6- Message Type Control Radio Buttons

These menus, Figure 12, are used to select which message type is coupled with the control object. The follwoing selections are available:

Act - Actual Position
Cmd - Command Positon
Des - Desired Position
Traj - Trajectory Position

The object and message selection combined designate the exact object being controlled. Therefore an input device attached to the actual position of Ranger could be manipulated. The desired, commanded and trajectory position for Ranger would remain unaffected. All other objects would also be unaffected.

7- Simulation Override Input Menus

Typically the vehicle display tracks the shared memory telemetry data. However if no telemetry or dynamic simulation is running, these menus, Figure 11, allow an input device to move the specified object. This menu is used to determine which object will be controlled by the input device.

The object and message selection combined designate the exact object being controlled. Therefore an input device attached to the actual position of Ranger could be manipulated. The desired, commanded and trajectory position for Ranger would remain unaffected. All other objects would also be unaffected.