These flexes use only 24 DOFs (3 per vertex of the bounding box), while colliding with the full high resolution mesh.
On an 8x8x8 cube, the performance using DOFs at all vertices is
```
Simulation time : 18.74 s
Steps per second : 533
Realtime factor : 0.53 x
Time per step : 1874.4 µs
Contacts per step : 114.88
Constraints per step : 3322.51
Degrees of freedom : 1536
```
With the new implementation, it is the following:
```
Simulation time : 1.82 s
Steps per second : 5507
Realtime factor : 5.51 x
Time per step : 181.6 µs
Contacts per step : 38.84
Constraints per step : 155.36
Degrees of freedom : 24
```
PiperOrigin-RevId: 721008829
Change-Id: I833df027527db578d86667cc4b24295bcf6f7d22
`flex_xvert0` stored the Cartesian position of the vertices in `qpos0`. This array was unused, so it is now replaced with `flex_vert0`, which still contains the positions of the vertices, but normalized on the bounding box of the flex so that the coordinates are in `[0,1]^m->flex_dim`. This will be useful in the future for using different interpolation methods for computing flex deformations.
PiperOrigin-RevId: 691779361
Change-Id: I5c4223103cd4558f4e268fe3e8d8177541e4754f
These functions names and argument ordering are more consistent with the rest of the API.
PiperOrigin-RevId: 643788290
Change-Id: I783eda8021b80b82098e23ed95669b102bb82508
- remove mj_crbSkip since this was only utilized during compile time to compute m->dof_m0, replaced with mj_crbDiag to compute only the diagonals for dof_m0,
- change row backward pass to forward pass to optimize processing diagonal blocks,
- and various code refactoring.
PiperOrigin-RevId: 556799924
Change-Id: I0a18d7a45862860fdddd7150540ddc8d64b01b29
If given two non-decreasing values, `springlength` specifies a deadband for spring stiffness, inside of which the force is 0 and outside of which force behaves like a regular spring, with the setpoint corresponding to the nearest value. This can be used to create tendons whose limits are enforced by springs rather than constraints, which are cheaper and easier to analyse. See test/engine/testdata/tendon_springlength.xml example model.
Spring-limited spatial tendons whose lower range value is 0 are rendered as catenaries.
Fixes#520.
PiperOrigin-RevId: 484509706
Change-Id: I6698e94ee36168f52d501e83057559805e05172d
- `anchor` determines the point of wrench application, in the frame of body2.
- `tfratio` scales applied torques relative to applied forces.
- Add visualisation of both anchor points to both weld and connect constraints.
- Add a test model showing how the new weld parameters behave.
PiperOrigin-RevId: 470021901
Change-Id: I3faba0e5dcab2e29ee81096f5ff71ff66d99758c
- `anchor` determines the point of wrench application, in the frame of body2.
- `tfratio` scales applied torques relative to applied forces.
- Add visualisation of both anchor points to both weld and connect constraints.
- Add a test model showing how the new weld parameters behave.
PiperOrigin-RevId: 469228149
Change-Id: I836b0791f10fb624607a12ef3c687da991c21789
- `anchor` determines the point of wrench application, in the frame of body2.
- `tfratio` scales applied torques relative to applied forces.
- Add visualisation of both anchor points to both weld and connect constraints.
- Add a test model showing how the new weld parameters behave.
PiperOrigin-RevId: 469190483
Change-Id: I20f6da85b09cd2c4c0b5d29eb8003eabb524e55e