View Full Version : Animation software: 1st Summary

Rene Steiner
08-31-1993, 08:25 PM
Dear BIOMCH-Lers:

Some time ago I posted a request for information about visualization
software currently in use in our field. It appears to me that my
timing may not have been the best because many of you were on vacation
at the time. However I have received some replies which I am going
to post now. I am still interested in further contributions, and therefore
I include a blank form, too.

Hope this is of some interest.


| Rene Steiner | |
| Neurologisches Therapiecentrum | phone: +49-211-7816-159 |
| Hohensandweg 37 | FAX: +49-211-784 353 |
| D-40591 Duesseldorf | |
| Germany | steiner@c1.rz.uni-duesseldorf.de |
| A nod's as good as a wink to a blind bat (Monty Python, Nudge Nudge) |

Date: Tue, 20 Jul 93 09:13:18 -0500
From: Glen Niebur
Subject: Re: Visualization Software


->Organization : Mayo Clinic, Biomechanics Laboratory
->email-address : gln@hercules.mayo.edu
->Visualization package used:
-> Availability ([non-]commercial, cost, supplier):
non-commericial, locally developed, Contact Mayo Medical Ventures
(507) 284-8878, or Kai An (507) 289-2043. Ask about LILA
-> Hardware requirements (machine type, display type, etc):
Any Silicon Graphics workstation
-> Area of application (whole body simulation, lower limb, etc.):
Whole body, individual joints, whatever you want
-> Representation (stick figure, wire frame, shaded solids, 2d, 3d, etc.):
3 dimensional shaded solids (with transparency)
->Input data:
-> Bodies (predefined geometric shapes, user defined, FE, etc.):
user defined shapes in BYU format
-> Displacement (absolute coordinates, Euler angles, etc.):
Euler Angles (XYZ order), Euler Parameters, Screw Axes
-> Link to simulation software (e.g. ADAMS/Android):
Input data can be directly output by Dwight Meglans ANZ software
->Output data:
-> Types of output (screen, printer, plotter, files):
Screen, printer, video
-> Data format (PCX, HPGL, etc.):
SGI image files
-> Link to animation software (e.g. AUTODESK Animator):
includes complete animation capabilities
-> Evaluation (usefulness, ease of use, recommendations, etc.):
Still under development. We have found it quite useful.
We continue to work on features, especially some graphing
capabilities to show for instance a graph of Moment or Force
versus time, or Moment versus Force etc. to be shown as the
animation is carried out.

Glen Niebur | I have lived my life with no regrets.
Mayo Clinic | I have seen my life with no regrets. It can be so lonely
Biomechanics Lab|
gln@mayo.edu | ~Tina and the B-side Movement

Date: Tue, 20 Jul 93 14:09:55 -0400
From: kepple%bmlvax.dnet@dxi.nih.gov

Dr Steiner:

Name : Thomas M. Kepple
Organization : National Institutes of Health (U.S.A)
email-address : kepple@bmlvax.dnet

Visualization package used: MOVE3D - (written at NIH)

Availability ([non-]commercial, cost, supplier):
Available at no cost (free).
Supplied by biomechanics laboratory at NIH.

Hardware requirements (machine type, display type, etc):
Silicon Graphics (can produce animation) or
Vax/VMS (can produce the same graphics as SGI but too slow for animation)

Area of application (whole body simulation, lower limb, etc.):
Whole body motion (simple wire frames, and stick figures)
Lower extremity moion (shaded solids with muscle lines)

Representation (stick figure, wire frame, shaded solids, 2d, 3d, etc.):
MOVE3D provides:
3d stick figures
3d simple wire frames
3d shaded solid (lower extremity only)

Input data:

Bodies (predefined geometric shapes, user defined, FE, etc.):
Predeined or user defined geomtric shapes (four geomtric shapes
are allowed).

For 3d shaded solids MOVE3D uses 3D wire meshes (plus estimated
muscle lines of action) generated from digitization done
at NIH and the National Museum of natural History.

Displacement (absolute coordinates, Euler angles, etc.):
In addition to graphics displays program can determine:

translation motion of segments or joints (includes displacements
velocities and accelerations)
rotational motion of segments or joints ( Euler or helical angles)
(includes displacements, velocities and acceleration)
net joint forces
net joint moments
net joint forces
net joint power

Link to simulation software (e.g. ADAMS/Android):
MOVE3D output is linked to ADAMS/ANDROID software. The output
data can be used as input to the ANDROID preprocessor;
automatically building the customized ANDROID model and driving
the joints with displacement-driven or torque-driven spline

Output data:

Types of output (screen, printer, plotter, files)
Graphics can be written to screen for the following devices:
TeKtronics 4014
Tektronics 4107
Regis graphics (VT340 or DecWindows)
Silicon Graphics

for 3D shaded solid graphics only the following devices are supported
Silicon Graphics

graphics output can be also sent to files
HPGL format
Tektronics 4014 format

numerical output can be directed to screen or output files

Data format (PCX, HPGL, etc.):
graphics can be sent to files in the following formats
Tektronics 4014 compatable

Link to animation software (e.g. AUTODESK Animator): None

Evaluation (usefulness, ease of use, recommendations, etc.):
Since I am author of the software I can not give an unbiased comment
on the software. I can provide the names an address of other
users not at the NIH.

DateDate: Tue, 27 Jul 93 11:42:41 SET
From: Alberto Leardini
Subject: Animation Software

Name : Alberto Leardini
Via Di Barbiano 1/10 40136 BOLOGNA (ITALY)
email-address : VI6BOQ71 at ICINECA.CINECA.IT

Visualization package used:

Availability (non-commercial, cost, supplier): Own developed in 'C' language
according to the specification presented at the
II International Symposium on 3D Analysis of Human Movement
(Poiters 30 Giugno - 3 Luglio)
Leardini A., Rinaldi G., Melandri R., Catani F. (POSTER n. 10)

Hardware requirements (machine type, display type, etc):
DOS Personal Computer, VGA color display

Area of application (whole body simulation, lower limb, etc.):
Actually for Pelvis and lower limbs. In the next future the
same methodology will be applied also to the trunk.

Representation (stick figure, wire frame, shaded solids, 2d, 3d, etc.):
Wire frame block for the body segment, and line for vectors
(Ground Reaction Force, Joint Moments)

Input data:

Bodies (predefined geometric shapes, user defined, FE, etc.):
Geometric block modelized to the subject anatomy, according to
position of anatomical landmarks

Displacement (absolute coordinates, Euler angles, etc.):
Absolute coordinates of at least three point for each segment,
collected during the execution of physical exercises of subject
with ELITE system

Link to simulation software (e.g. ADAMS/Android): NONE

Output data:

Types of output (screen, printer, plotter, files): At the moment only screen

Data format (PCX, HPGL, etc.):

Link to animation software (e.g. AUTODESK Animator): NONE

Evaluation (usefulness, ease of use, recommendations, etc.):

A graphic and animation software program was written in 'C' language, linked
with standard graphic library to visualize the wire frame images of each body
segment. The software package can show the position of each body segment for
each sampled frame from each 3-D spatial view: using a user-friendly menu you
can translate, rotate and zoom the user point of view. It is also
possible to visualize a series of successive images rapidly, one after another,
to reproduce the effect of real movement. The user can also select the
representation of anatomical landmark points, ground reaction force and joint
moments separately.
The anatomical based model of lower limb segments, gained by anatomical
landmarks calibration,allows a good representation and visualization of subject
anatomy and joint conformation, in order to immediately detect any subject's
pathological problems, like knee deformity, and look at their consequences in
his locomotion pattern.Finally,in visualizing the ground reaction resultant
force with respect to joints center of rotation, it is quite easy to look at
the joints moment changes.
For these who focus for the first time with gait analysis data, it is often
particularly difficult to understand the mechanical meaning of the
biomechanical functions and their clinical importance. This 3D restitution
could be a good tool for educational purposes. The easy-to-use package can
run in common personal computers and does not require specific graphic
devices and long time elaboration; this allows its use in routine clinical
gait analysis context. There are no methodological problems in extending
this representation to total body movement.

From: dapena@valeri.hper.indiana.edu
Date: Sun, 15 Aug 93 09:39:53 -0500
Subject: Re: Visualization Software form

Name : Jesus Dapena
Organization : Dept. of Kinesiology, Indiana University, Bloomington,
IN 47405 (USA)
email-address : dapena@valeri.hper.indiana.edu

Visualization package used:


Availability ([non-]commercial, cost, supplier):

Non-commercial, free of cost

This software is available via anonymous FTP. Individuals wishing to

obtain their own copies of the software should use FTP through the

Internet network:

ftp valeri.hper.indiana.edu (or ftp
To the prompt "Name", answer: anonymous
To the prompt "Password", answer: anything
You will find yourself in the directory "ftp"
Then type the following:
get mainjmp.f

If you have any problems, contact Jesus Dapena at the following e-mail

Hardware requirements (machine type, display type, etc):

The program is independent from machine or display type. In our lab
we use it with a NeXTStation TurboColor computer.

Area of application (whole body simulation, lower limb, etc.):

Whole body

Representation (stick figure, wire frame, shaded solids, 2d, 3d, etc.):

3D wireframe

Input data:

Bodies (predefined geometric shapes, user defined, FE, etc.):

Needs height, mass and gender of subject as input.
Segmental shapes are built-in. Segment thicknesses are estimated from
subject height and mass.

Displacement (absolute coordinates, Euler angles, etc.):

Absolute coordinates of 21 body landmarks;

Link to simulation software (e.g. ADAMS/Android):
No link to any widely-available simulation software at this point

Output data:

Types of output (screen, printer, plotter, files):

Data format (PCX, HPGL, etc.):
Standard UNIX plotting package "plot"

Link to animation software (e.g. AUTODESK Animator):
In our lab, it is linked to an animation program called
"CicaAnimator" specific to NeXTStep. (CicaAnimator
itself is also available.)

Evaluation (usefulness, ease of use, recommendations, etc.):

The programs are in FORTRAN. GRAFATH comes together with two other
graphics programs (STKFIG and CYLBOD) that use simpler body models, a
sample main program (MAINJMP) which calls the graphics programs, and a
series of auxiliary subroutines. Apart from serving as a sample main
program, MAINJMP contains instructions for changing the direction of
viewing. The graphics programs do not allow for changes in the
observer-to-object distance: All drawings correspond to a view from an
infinite distance with a telephoto lens of infinite focal length.
GRAFATH estimates the curvature of the trunk segment from the
orientations of the thighs relative to the line joining the mid-hip to
the suprasternale.

We are currently developing SOLFIG, a shaded solids version of GRAFATH.)


Finally, an out-of-format description of the SIMM package:

Date: Fri, 25 Jun 93 17:29:41 -0500
From: dmeglan@merle.acns.nwu.edu (Dwight Meglan)
Subject: Survey of Animation Software


SIMM (Software for Interactive Musculoskeletal Modeling) is a
graphics-based software system that enables the user to quickly develop
and analyze musculoskeletal models. In SIMM, a musculoskeletal
model consists of a set of rigid body segments that are connected by
joints. Muscle-tendon actuators span the joints and develop force,
thus generating moments about the joints.

SIMM enables a analysis of a musculoskeletal model by calculating the
joint moments (i.e., muscle force multiplied by moment arm) that each
actuator can generate at any body position. By manipulating a model
on the computer graphics system, the user can quickly explore the effects
of changing musculoskeletal geometry and other model parameters on
the muscle forces and joint moments.

Since the software can be used to study many different musculoskeletal
structures, it can enhance the productivity of investigators working
on diverse problems in biomechanics.

Design Goals

Four goals were established in designing and implementing the software.
Specifically, it should:

* Be general enough so that a wide variety of musculoskeletal
structures can be modeled

* Provide realistic models of muscle and tendon, and allow accurate
specification of joint kinematics

* Provide an interactive, graphics-based environment so the model can
be visualized, altered, and analyzed efficiently

* Be extensible so that new features, such as a more complex
muscle-tendon model, can easily be added to the software

Major Features

* Enables users to develop models of any musculoskeletal structure,
either human or animal. Current uses include the human lower
extremity, elbow, shoulder, finger, and even a cockroach leg.

* Displays lighted, smooth-shaded three-dimensional images of the models

* Provides an intuitive graphical interface for manipulating the models

* Allows analysis of models by computing muscle forces, moment arms,
and joint torques

* Can read-in and "playback" animations of experimentally recorded or
simulated movements, for example walking or cycling.


SIMM has applications in many areas involving biomechanics. SIMM can
increase the productivity of:

* Researchers investigating various issues in biomechanics, such as
muscle coordination and joint reconstruction

* Medical students and residents studying musculoskeletal anatomy and

* Kinesiologists recording the motion of patients with movement

* Workspace designers studying the ergonomics of various devices and

* Computer scientists creating human body models for virtual realities

The SIMM Environment

A musculoskeletal model is specified with three types of input files.
The bone files contain lists of the polygons representing the bone
surfaces. The joint file specifies the kinematics of each joint.
Finally, the muscle file contains a list of coordinates that describe
the line of action of each muscle-tendon actuator, and the parameters
needed to compute muscle force. The File Loader tool scans these input
files and creates a data structure that represents the
musculoskeletal model.

SIMM allows the user to load one or more musculoskeletal models by reading
sets of input files. Once loaded, a model can be acted upon by a
number of editing and analysis tools. Each tool is contained within
its own window and has a distinct function. These tools include the
Model Viewer, Muscle Editor, Joint Editor, and Plot Maker.

The Model Viewer tool controls the user's view of the musculoskeletal
models. Individual muscles can displayed or hidden, the bones can be
shaded or shown in wire frame, and three-dimensional views can stored
and recalled. Slider bars can be used to move each of the joints
individually, or the entire model can be animated.

The Muscle Editor tool gives access to the parameters that describe a
muscle. Muscle paths can be interactively altered, for example to
simulate tendon transfer surgery. The parameters that govern the
force generating behavior of the muscles can also be changed.

The Joint Editor tool enables the user to view and alter joint
kinematics. The cubic splines that control the movement of the joints
can be graphically changed. The resulting joint motion can be
examined instantly by viewing the model.

The Plot Maker tool allows the user to analyze a model by creating plots
of muscle forces, moment arms, and joint torques. Many options are
available for creating plots and graphing data from other sources (for
example experimental data). The plotted data can also exported as text or
postscript for use in other applications.

Hardware Requirements

SIMM runs on the full line of workstations from Silicon Graphics, Inc.


This software is commercially available and comes with a user manual and
input files that define a model of the human lower extremity. This model
is described in detail in the following documents:

Delp, S. L., "Surgery Simulation: A Computer Graphics System to
Design and Analyze Musculoskeletal Reconstructions of the Lower
Limb," Ph.D. Dissertation, Stanford University, 1990.

Delp, S. L., Loan, J. P., Hoy, M. G., Zajac, F. E., Topp, E. L.,
Rosen, J. M., "An interactive graphics-based model of the lower
extremity to study orthopaedic surgical procedures," IEEE
Transactions on Biomedical Engineering, vol. 37, pp. 757-767, 1990.

Companion Products

The engineers at MusculoGraphics are currently developing a companion
product called the Dynamics Pipeline. This software links SIMM to
SD/FAST (Symbolic Dynamics, Mountain View, CA), which simulates the
dynamics of rigid-body systems. With the Pipeline, the user is able
to perform forward and inverse dynamic simulations on any
musculoskeletal model developed in SIMM, without writing any
software. For forward dynamics, the user can specify muscle
activation levels and compute the resulting motion. The Pipeline
includes several dynamic muscle models from which the user can choose
based on his speed and accuracy demands. For inverse dynamics, the
user specifies the trajectories of the body segments over time, and
the Pipeline computes the joint torques required to create the
motion. If the user wants to perform more complicated analyses
(e.g., optimal control of muscle activations or collision detection
between body segments), they can write the software to implement
these features and easily link them into the Pipeline. It is
anticipated that the Dynamics Pipeline will be available by end of 1993.

Further information can be obtained from:

MusculoGraphics, Inc.
1840 Oak Avenue
Evanston, IL 60201 USA

(708) 866-1882
(708) 866-1808 : FAX