The Dynamics Equations Solvers
(dynawiz1.dll and dynawiz1.exe) in our MDS
programs are based on a
recursive algorithm that accommodates arbitrary number of bodies that are
connected in a tree configuration. Contact constraints can be activated to allow
closed loop configurations during run-time. Prescribed motion can also be
implemented to test the 'what if' cases. Furthermore, each member body can be
rigid or flexible. The deformation of a flexible body is defined by a linear
combination of finite number of assumed mode shapes defined over it. The execution speed
of the equation solvers is Order(N + sum(ni3)),
where N= number of bodies, and ni= number of flexible
modes for the i-th body.
The Dynawiz1.dll program
runs in the
Matlab/Simulink(c) environment. The Dynawiz1.exe
program runs on any PC that has C/C++ compiler installed. These programs
are included in the packages.
XSV Packages
simulates aircraft and satellite dynamics, and our XMR packages
simulates
robotics and mechanisms. The QX3D program in these packages
lets you visualize/animate the simulated objects.
These packages provide:
-
High fidelity dynamics simulations
-
Fast executions
-
Versatility. They
accommodate rigid, flexible, inverse, and constraint dynamics
-
User-friendly fast and
efficient model setup.
-
Easy plots generation from the simulations.
-
Easy visualization/animation
of simulated
vehicle/mechanisms on your browser.
Tutorial
Each example downloaded from the xsv
and xmr pages comes with instructions that
explain the model building and the vehicle simulation processes. The Buildx editor
engages you interactively to define the
mechanical attributes of the modeled mechanism: mass property, member body
connectivity, interbody degrees of freedom, and so forth. If you click on any of
the examples in the Models table below (first column), a short pdf
file of the selected example will show the procedure to create and simulate
that example. Your browser must be VRML compatible to view a static view or an animation of
an example by clicking
on the associated view/animate fields. Otherwise, we recommend that you
install a VRML plug-in to enable the viewing the VRML
images and animations created by our QX3D program.
VRML plug-in suggestion: go to www.parallelgraphics.com
and install cortvrml.exe
Downloads
See the capabilities of the XSV and the XMR packages (Simulink and
DOS/C++ implementation) by downloading them
and examples from the xsv_download page
and the xmr_download page.
|
XSV Models |
| Cube |
view/animate |
A single body satellite |
| Cube_3wc |
view/animate |
A single body with 3 wheels for attitude control |
| Sat001 |
view/animate |
A satellite with two arrays. Each array has two panels. The
bus has 3 wheels for attitude control. Simulates an array deployment. |
| Sat_3panel |
view/animate |
A satellite with two arrays. Each array has three panels.
The bus has 3 wheels for attitude control. Simulates an array deployment. |
| Dual_spnr |
view/animate |
A dual spinner with two jets on the rotor for spin-up. |
| Cmg_sim |
view/animate |
A satellite with 4 control moment gyros for attitude
control. Simulation demonstrates open loop slewing of the satellite along
three body axis individually. |
Two_sat |
view/animate |
Two satellites are initially attached to each other drifting
in a LEO circular orbit. At 10 seconds into simulation, they are separated by a force pulse at the interface plane. One vehicle
reorients itself into the LVLH attitude, the other
maintains attitude hold. Gravity gradient forces/torque are exerted on the
satellites throughout the simulation. |
Chain20 |
view/animate |
A satellite with 19 panels floats in a geosynchronous orbit.
Its initial bus angular rate is [1 2 3] deg/sec.
No external force is applied. |
| XMR Models |
| Robot_arm1 |
view/animate
|
This is a six link robot arm, where all hinges
are 1 dof rotational joints. It moves from a vertical
configuration to a commanded configuration in about 30 seconds. Gravity
force is in effect. Each joint is a 1 dof revolute joint. |
| Stanford_arm |
view/animate |
This is a six link arm, where all hinges are 1
dof rotational joints except for the third hinge which is a 1 dof
translational joint. The arm is in a zero gravity condition. Initially,
the joint(2) is at a 90 deg position with a -5 deg/sec angular rate. When
the simulation starts, a 1 Hz force pulse is sent to the translational
joint for 20 seconds. The simulation runs for 30 seconds. No feedback
control is employed |
| Bouncing |
view/animate |
A ball falls from 10 ft along z-axis, with a 0.5
ft/s velocity in the y-axis. The ball is 1 ft in diameter, rotates
initially with [30 30 30] deg/s with its cm offset at [.05 .05 .05] ft
from the ball center. The ball bounces in the +y direction with lower
height with each bounce. |
| Three_bar |
view/animate
|
A three bar link is simulated with the tip of bar 3 anchored
initially. This anchor constraint is removed at 10 seconds into the
simulation. The motion of the three bar link is driven by the gravity
force. |
| Pendulum |
view/animate |
A pendulum swings from a near upright initial
condition. A friction torque dampens that swing over time. |
| Dbl_Pendulum |
view/animate |
Two pendulums, 2 ft apart, swing under the
action of gravity. There is also a pair of spring & damper force that
pushes at the mid point of the two pendulum. A friction torque at the base
of each pendulum dampen that swing over time. |
| Inv_Pendulum |
view/animate
|
An inverted pendulum is mounted on a wheeled cart. Gravity acts on the pendulum.
Lateral motion of the cart is the only control
available to prevent the pendulum from falling down. The pendulum is
initially tilted 10 degrees away from vertical. A linear controller with a
controlled angular bias is used to keep the pendulum upright and move to a
commanded position. |
| Engine_4cyl |
view/animate
|
A four cylinder 4-stroke internal combustion engine. A motor starts the engine. Each piston
has a
simple burn profile on the combustion stroke with a peak force that can be
set in the Simulink model. (Animation file takes a little time to
display.) |
The downloads are free and they
run with a demo license. This license gives you reduced model
editing features as compared to the full capability license. See the distinction
between the two licenses at the xsv_download
and the xmr_download pages.
Your are welcome to visit our other sites
[Spacecraft][Robotics][Animation]
Recommended websites:
- Multibody System Dynamics- Research
Activities ( http://real.uwaterloo.ca/~mbody/ )
- A Collection of Modeling and Simulation Resources on the Internet ( http://www.idsia.ch/~andrea/simtools.html
)
- Directory of Software Related websites (http://www.the-science-lab.com/Software/
)
Thank you for visiting us!
Please send your
comments and inquiries to support@concurrent-dynamics.com.
