The Poseable Hand CAD model is developed and distributed by CADHuman. It is a phantom model containing left and right hands and forearms. XF recognizes and applies attributes to this CAD model, allowing users to reposition the fingers.
Obtain a Poseable Hand
The Poseable Hand can be purchased directly from CADHuman.
Upon purchasing, a webpage provides a list of hands in various formats. Users should download the XFdtd Compatible version.
The download consists of Poseable Hands XFdtd.zip containing Poseable Hands Main.Assembly.SAT. The SAT file contains both the left and right hand and forearm models.
Import a CAD Model
Similar to any CAD model, import the Poseable Hand model using the File ❯ Import ❯ CAD File(s) menu in the upper-left corner of the XF window. Navigate to the saved SAT file and select it to be opened.
A dialog appears, prompting the user for input:
- Yes: processes the model and automatically prepares it for positioning in XF.
- No: proceeds with the standard geometry import process through the CAD Import Options dialog.
After import, the Parts node of the Project Tree will contain two assemblies—Poseable Hand Right and Poseable Hand Left—each of which expands to show its various components.
Users should note that the Poseable Hands are presented in the project tree in the same manner as all geometry, meaning the assembly structure and its parts can be inspected and edited. It is suggested that users not edit or perform specify orientation operations on any parts of the Poseable Hand structures because it would likely result in unintended behavior when editing them according to the Poseable Hand editor describtion below.
Directly after import, the hands in the Project Tree will not have a material assigned to them.
Add a Material Definition to the Project from a library and assign it to the assemblies with the following steps:
- Open the Libraries window from the View ❯ Libraries menu.
- Select the Materials - Other library in the upper-left pane.
- Add the material to the Project by dragging and dropping the CTIA Phantom Hand [ND] material from the bottom pane of the library to the Materials branch in the Project Tree.
- Assign the material by dragging and dropping the Material Definition from the Materials branch of the Project Tree to the Poseable Hand Right and Poseable Hand Left assemblies.
Manipulate Fingers and Thumbs
XF recognizes the Poseable Hand model and applies controls for its joints and palms during import. Open the Poseable Hand Editor by right-clicking on Poseable Hand Right and selecting Edit Poseable Hand.
The editor opens and provides capabilities specifically designed for manipulating the Poseable Hand. The Default button in the upper-left corner resets all of the fingers to their default positions.
For any interaction with the drag handles, hold one or more of the Ctrl, Shift, and Alt keys when clicking to slow down the motion. The more keys that are held, the slower the motion will be.
Click on the finger just above the desired joint, then use the drag handles to rotate the joints by moving the mouse left or right while clicking.
The finger joints show only the one or two axes of rotation appropriate for that joint. Holding Shift+Ctrl+Alt while clicking to select a joint shows all three axes. Users should note that the movement of the fingers is not restricted.
Match the Hand to a Device
The Hand - Device Matching tools assist with matching the hand and its fingers to another part in the geometry.
Once the hand and fingers are close to the desired position, users determine three sets of two matching points between the hand and the device.
For example, holding a cell phone with a right hand matches the following points:
- P1 set: The pad of the index finger on the upper corner of the back of the phone.
- P2 set: The end of the pinky finger on the lower-left side of the phone.
- P3 set: The pad of the thumb on the upper-right side of the phone.
These points are typically determined by carefully examining an actual hand holding a device for the best result. The task then is to select these three sets of points, P1, P2 and P3. The image shows a transparent phone, Hand points as filled blue markers (P1=diamond, P2=square, P3=triangle), and the Device points with corresponding hollow markers.
A on any of the P1-3 buttons indicates that those points have not yet been picked. Users should note that the picker auto-advances according the the Auto-advance checkbox as selections are made. The selected six points will remain active while the editor remains open. The Clear button clears the points and toggling the Show Points checkbox shows and hides them.
Clicking the Match button applies an algorithm that orients the hand and minimizes the distances between the pairs of points. Matching is a one-time operation, allowing changes to the model at any time and matching to be redone after making those adjustments.
Reuse a Positioned Hand
Once a hand has been positioned for a specific orientation and phone size, at least three options exist.
The rest of the project should be set up and prepared for simulation if the position is for experimental purposes and not intended for anything else.
XF can copy the finger positions of one hand to the other when the device will need to be held with the opposite hand in an identical manner. Or, the device will be held with both hands in a symmetric manner, similar to a landscape. This is accomplished by using the Ctrl key to select both hands in the Project Tree, right-clicking, and choosing Copy Finger Positions. A prompt will ask the user which hand will be matched to the other hand.
The position may be shared with team members when prepared for production design. The hand and any additional positioning geometry can be put into a shared library from which other engineers can drag and drop the hand. This is accomplished by creating a Library in the Library window and dragging and dropping the hand into it.