Frequently Asked Questions (FAQs)

What is the difference between ViVA and VIVA+?¶

ViVA was a simplified Human Body Model of an average female developed at Chalmers. This model was designed to have a fairly detailed cervical spine representation complemented with a coarser definition for rest of the body, mainly as a boundary condition for the neck.

VIVA+ is a completely new lineup of models, which include occupant and standing models of average female and male, but following in the Open Source footsteps of the ViVA model. It has a detailed geometry and material definition for tissue-based injury prediction in many body regions. For example, in v1.0.0, the models have a detailed representation for the ribcage and the lower extremities.

Open Source¶

Can I use VIVA+ models along with proprietary models (like vehicle models)?¶

VIVA+ uses the LGPL v3 license, which means the human body models and proprietary models can be linked dynamically, for example, using “includes”.

Using an open-source model/library does NOT imply that you are required to share your work and associated models openly. Open source license provide you the freedom to use and modify without resharing the VIVA+ models. Neither the proprietary models used along with the VIVA+ models nor the simulation outputs inherit the open-source license of VIVA+.

Read more from FSF FAQs:


### **Can I modify VIVA+ models and share again?**

**Yes**, you are free to **make any changes** to model as needed for your requirements, and you are also free to **release** the modified model publicly.

If you release the modified model, you need to use the **same license** and **you cannot publish it as a VIVA+ model**.
VIVA+ is trademarked, and only models released by the VIVA+ Steering group are labelled as VIVA+. 

If you would like to contribute your modification or updates to a future release of the VIVA+, contact the maintainer team at vivaplus@ovto.org or let us know by starting an [issue](https://openvt.eu/fem/viva/vivaplus/-/issues/new?issue%5Bassignee_id%5D=&issue%5Bmilestone_id%5D=) on VIVA+ repository at OpenVT platform.

```{admonition} Read the license text
:class: note dropdown

```{code-block}
:caption: "GPLv3 Section  5. Conveying Modified Source Versions."

You may convey a work based on the Program, or the modifications to
produce it from the Program, in the form of source code under the
terms of section 4, provided that you also meet all of these conditions:

    a) The work must carry prominent notices stating that you modified
    it, and giving a relevant date.

    b) The work must carry prominent notices stating that it is
    released under this License and any conditions added under section
    7.  This requirement modifies the requirement in section 4 to
    "keep intact all notices".

    continued...

Why does the GPL permit users to publish their modified versions? FSF FAQ





### **As an industry user, can I send VIVA+ models to a subcontractor to make exclusive changes for me?**

Yes, under the LGPL license, you are allowed to send it to a subcontractor to have specific changes made for your use.

```{admonition} Read the license text
:class: note dropdown

```{code-block}
:caption: "GPLv3 Section 2. Basic Permissions."
You may convey covered works to others for the sole purpose
of having them make modifications exclusively for you, or provide you
with facilities for running those works, provided that you comply with
the terms of this License in conveying all material for which you do
not control copyright.  Those thus making or running the covered works
for you must do so exclusively on your behalf, under your direction
and control, on terms that prohibit them from making any copies of
your copyrighted material outside their relationship with you.

Read more from FSF FAQs:


### **Open and Free-of-cost? How do you assure the quality and stability of VIVA+ models?**

All the **versions** downloaded from the VIVA+ homepage are stable releases made after extensive **robustness tests** and **validation evaluations**[^1].
All the past stable releases can be accessed on [Zenodo](https://doi.org/10.5281/zenodo.7789362).
The model repository (with detailed history of updates to models[^2]), along with models tests and validations are openly available on OpenVT.
Anyone can test VIVA+ for reproducibility of its validation reported on our Validation Catalog on their own computing platforms using our openly available tests and validations.

### **Can I use VIVA+ for Euro NCAP virtual testing?**

VIVA+ `v2.0.1` is qualified for Euro NCAP CP550. The qualification reports are at [viva-certification.readthedocs.io](https://viva-certification.readthedocs.io/en/latest/), and the simulation setups and results submitted for certification are on [OpenVT](https://openvt.eu/vivaplus/cp550/vivaplus-cp550-qualification-s3). Use `v2.0.1` for CP550 assessments; you can [download it from Zenodo](https://zenodo.org/records/15482401/files/vivaplus-v2.0.1.zip?download=1).

<!-- TODO(convert): MkDocs code annotations `{ .annotate }` converted to footnotes. -->
[^1]: [release guidelines](../contributor-guide/release-guidelines.md) for Model Maintainers
[^2]: here is the [CHANGELOG](https://openvt.eu/fem/viva/vivaplus/-/blob/main/CHANGELOG.md) file on OpenVT


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**Why are there no internal organs?**

The internal organs and soft tissues are 

**Why do you say the whole lineup of models are a derivative of the average female?**
The design philosophy
The derivatives have the same elements, but with different nodal coordinates. -->

Frequently Asked Questions (FAQs)

What is the difference between ViVA and VIVA+?¶

Open Source¶

Can I use VIVA+ models along with proprietary models (like vehicle models)?¶

Can I modify VIVA+ models and NOT share the changes?¶