Add an optional `const char* args` field to `mjResource` to allow passing
resource arguments/hints (such as requested channel count or encoding options)
to resource decoders and encoders.
PiperOrigin-RevId: 959774058
Change-Id: Icc41a2bb3895fef24f98c5fa9a77cdad092a6bc7
This avoids unnecessarily resetting the bvh_active flags when the collision driver returns early due to disabled constraints, disabled contacts, or having fewer than two bodies/flexes.
PiperOrigin-RevId: 959531283
Change-Id: I85caf054b06e3be1018d710f9ab762627fc3356a
This change defines rotEPS as 1e-6f when mjUSESINGLE is defined, and 1e-9 otherwise. With the larger epsilon for single precision, the algorithm converges in fewer iterations, allowing the test assertion for maximum iterations to be simplified to a constant 150.
PiperOrigin-RevId: 959070496
Change-Id: I4f6fae056cd71955d3921c01a9929af2cdd81fac
Interpolated flexes with pinned nodes could not be reloaded after saving:
pinned nodes share their parent body, and their positions within it lived
only in mjsFlex.node, which had no MJCF attribute. On reload the pinned
nodes collapsed onto the parent body origin, degenerating the trilinear
interpolation grid ("flex grid rotation R0 is not orthonormal"). This
made model/flex/strain.xml and gripper_trilinear.xml fail to round-trip.
Add flex/nodecoord, real(3*nnode), the node analog of flex/vertex: local
node coordinates within the corresponding body frames. The reader picks
it up from the regenerated schema tables; the writer emits it with the
precision-aware WriteVector, since VectorToString ignores the XML
precision setting and truncating node coordinates to 6 digits while body
positions carry 17 fails the R0 orthonormality check at full precision.
Add a WritesPinnedFlexNodes round-trip regression test, and remove the
two write-read sweep exclusions documenting this bug. The removed
substring filter "strain" was also matching core_constraint, silently
excluding that entire testdata directory from the sweep; its ~40 models
are now covered and pass.
PiperOrigin-RevId: 959025281
Change-Id: I2fed28c01491c5a8431e813102a423d12b659911
- Declare every nonzero default; make the defaults cross-check total.
- Skip default-valued attributes in the hand-written writer paths.
- Fix type facts on hand-read elements, found by the dm_control diff.
PiperOrigin-RevId: 958999733
Change-Id: I3064ccc6ae1f049c20f273abc234cd02990a8b7e
- Declare the full child lists of the body-alias elements.
- Verify read-table coverage: every generated row array must be consumed.
- Fix stale attribute facts on hand-read elements.
PiperOrigin-RevId: 958685667
Change-Id: I4a914f3136a5078eb8ca24aa4e162d55afafd923
K_stretch was the Gauss-Newton Hessian of the stretch force, not its Jacobian.
With elongation e_a = L_a^2 - L0_a^2 and force f = -sum_ab M_ab e_a grad(e_b)/2,
K = 2 sum_ab M_ab (s_a d_a)(s_b d_b)^T + sum_a Me_a (Laplacian_a (x) I3)
and only the first term was there. The second is proportional to the edge
tension Me_a = sum_b M_ab e_b, so it vanishes at rest and grows with strain:
the operator was first-order correct and no more. Finite-differencing it
against -d(qfrc_passive)/dq on a mesh dilated by 5% gives 7.8% of the force
scale; with the term it is exact to roundoff.
Add only the tensile part. The geometric block is Me_a*[[I,-I],[-I,I]] over the
edge's two vertices, which is positive semi-definite exactly when Me_a >= 0; a
compressed edge would make K indefinite, and both consumers -- the CG
constraint solver and the PCG in mjd_effSolve -- require SPD. The clamp is
structural, so no eigendecomposition is needed, and it is confined to the
operator: mj_flexPassiveStretch keeps the full Me_a, so no force changes.
Both the matrix-free operator and the CSR assembly the effective metric builds
from are updated, since they must agree.
This changes how flexes with elastic2d="stretch" integrate under the implicit
integrators and the effective metric -- bag.xml moves, poncho.xml is
bit-identical because bending energy is quadratic and has no geometric term.
The interpolated-flex path still uses its Gauss-Newton approximation, which
FlexInterpDerivativesDeformed asserts.
The writer consumes the same generated rows as the reader.
mjXWriter::WriteAttrTable drives the mechanical attributes of an
element from its mjXAttr rows: each bound field is compared against
the class default at the same offset -- the default object is the same
struct type, so the rows carry no comparison values -- and attributes
equal to their default are skipped. A null default object means the
element has no defaults, and every defined value is written.
Ranged-arity rows write with trailing-default trimming, which the
reader makes round-trip exact by refilling from the same default.
Call sites upcast to the private mjs base (the friend declarations
permit it; mjCMesh gains the friendship its siblings had); the
comparison object is def->X().spec, a freshly-defaulted struct for
the sections, or zero-initialized for size, whose spec defaults (-1,
auto) are resolved by compilation.
Converted: pair, geom, site, joint, camera, light, material, the
equality family, both tendon types (the fixed rows are the spatial
rows without appearance attributes -- exactly the tag difference), the
actuator, flex with its three sub-elements, mesh, skin, option, the
six visual sub-sections, statistic and size. The remnants keep names,
files, resolved reference strings (the mjC classes null their private
base's string pointers; resolved names live behind accessors), and the
writing=custom policies the schema declares: compile directives never
saved (fromto, springdamper, fitscale), type-dependent lengths and
attributes (sizes, joint pos/axis/limited, shellinertia), and
alternatives (mass/density, fovy-versus-intrinsics, the plugin-gated
gain/bias family). Compiler keeps its write-if-nonzero policy;
keyframe keeps its model-sized vectors.
Saved files are canonical: attributes follow schema declaration order
with remnants trailing, and sections follow the schema's dependency
order (statistic before visual, deformable before the contact and
equality sections that name flexes, tendon before the equality
constraints that name tendons, custom demoted to the data tail).
Uniform behavior fixes fall out: default-equal positionals are
dropped, dynprm is trimmed like every other ranged vector, and mesh
material -- read into the spec but never written -- now survives
save/load round trips. Changelog entries ride along.
Verified: full suite, doc_test, and the two-tier A/B harness --
saved XML reorders attributes, and every corpus model reloads to a
byte-identical binary.
PiperOrigin-RevId: 958255003
Change-Id: I5fe7346014450db88b2f3f8680a8f616f7d31266
Every mechanical attribute read in MJCF now derives from mjcf.schema.
generate_read_table.py emits typed mjXAttr rows (mjcf_read_table.inc,
doc_test-gated) binding each attribute to its spec struct field; field
offsets are offsetof() expressions, so binding mistakes are compile
errors, and the field's C type -- parsed from the headers -- selects the
row kind, so mjtNum-versus-double is decided by the struct, not the
schema. mjXReader::ReadAttrTable is the generic loop; its static core
also serves the section parsers and records XML-authored fields via
mjs_setAuthored for attach conflict resolution. Row kinds cover
strings, string lists, numeric scalars and vectors (exact and ranged),
enums (int- and byte-width), bitwise flag sets, bools, unbounded typed
vectors, fixed char arrays, and identity constants declared by 'set'.
The rows are inline variables, and carry the writing=custom flag,
because the writer will share them.
The keyword maps the rows reference are generated too: the ~48
hand-written mjMap tables become mjcf_map.h, one map and size constant
per enum as C++17 inline variables, retiring the hand-maintained
extern block in xml_base.h. Map names follow the schema enum names
(fluid->fluidshape, TFAuto->FalseTrueAuto, FAuto->FalseAuto,
joint->jointtype, geom->geomtype, jac->jacobian); all maps are
key-order- and value-identical to the hand tables they replace, and
bool_map is hand-emitted (the bool type is built in, not a schema
enum).
The OneX() parsers reduce to genuine irregulars, schema-marked as
reading=custom: orientation alternatives, file attributes (VFS and
asset-dir context), the actuator shorthand remappings and per-type
input maps, springlength's one-value copy, mesh builtin construction,
hfield elevation, texture cube files, flexcomp seeding, the memory
suffix parse, and the flag bit families. All 41 sensors that are pure
identity-plus-references -- including the frame family and insidesite
-- dispatch through a generated tag table; frame-sensor
objtype/reftype vocabulary tightens from the full mju_str2Type
namespace to the documented body/xbody/geom/site/camera subset, so an
invalid keyword now fails at parse time instead of compile time. The
equality family and both tendon types read shared group rows; the
twelve actuator shorthands share the general rows, with per-tag
legality enforced by the schema check. Sections bind non-mjs structs,
the visual sub-sections reaching their anonymous sub-structs through
member paths declared by an element-level field= facet.
Latent irregularities surfaced by the migration and preserved via
schema declarations or remnants: key's name is set even when absent,
eulerseq and gridlayout are fixed char arrays (chars[n], arity in
characters), gridlayout's length-must-match-gridsize stays a
value-conditional remnant, and constructor-style elements (tendon
wraps, asset model, replicate, attach) are annotated as such -- their
attributes are arguments, not field writes.
Two coherence tests guard the schema against the C sources: every
schema enum constant must be a member of the C enum it claims, and
every C member must be a keyword, a count sentinel, or a documented
exemption; and generate_default_table.py emits one row per defaulted
attribute (mjcf_default_table.inc), compared by SchemaDefaultsTest
against a freshly-constructed spec -- the schema cannot disagree with
the C default-constructors without failing the suite.
Verified: doc_test regenerates and diffs every artifact; the full
suite; and an A/B harness compiling the model corpus against the
pre-migration reader -- saved XML and binary models are byte-identical.
PiperOrigin-RevId: 958075724
Change-Id: I9715fe4deeb438eec988fd5084d74ba8b466b10b
The hand-written MJCF[] table in xml_native_reader.cc is replaced by
mjcf_table.inc, emitted from mjcf.schema by generate_mjcf_table.py and
checked for freshness by doc_test. nMJCF is now self-sizing. The two
tables are identical as trees of (tag, cardinality, attribute-set);
within-row attribute order changes where the schema factors shared
groups and projects default-context rows, and top-level rows follow
the schema's dependency order -- neither affects validation, which is
set-based, nor XMLschema.rst, whose generator orders sections itself
(regenerated here, reading the .inc instead of the reader source).
The schema's constraint declarations become enforcement: the emitter
writes a companion MJCF_constraints[] array (row-indexed into MJCF[]),
and mjXSchema::Check evaluates each element's constraints after its
attribute check, with uniform messages derived from the declaration:
"at most one of 'fovy', 'sensorsize' can be specified", "attributes
'reftype', 'refname' must be specified together", and so on.
Multi-attribute bundles render as ('site1', 'site2').
Fifteen hand-written co-occurrence checks across fourteen elements are
deleted -- connect/weld semantics mixing and completeness, the actuator
transmission mutex, camera fovy/sensorsize, light directional/type,
inertial fullinertia-versus-orientation, rangefinder and the distance
family, contact's matching criteria, user-sensor pairing, the frame
family's reftype/refname, size memory exclusivities, mesh builtin
exclusions, and attach body/frame (newly declared). Tests assert the
uniform messages.
Two findings along the way: sensorsize-requires-resolution is a
value-level compiler rule (positive resolution), not a presence rule --
a presence constraint would be wrong and is not declared; and Size()'s
nstack/njmax range checks tested the spec value before assignment, so
they never validated the parsed value -- now they do.
Verified by compiling all 81 models in the model/ corpus.
PiperOrigin-RevId: 958064622
Change-Id: I802cf5c0aee08a62926e36a281320ff9e34c0668
The complete MJCF surface in one hand-maintained file: 144 elements, 8
shared attribute groups, 47 enums, 1,497 typed attributes with
defaults, the presence-constraint inventory previously visible only as
hand-written reader checks, and the save policies previously visible
only as hand-written writer logic.
The language is a small IDL: elements bound to their mjSpec structs,
typed attributes with arities and defaults, enum keyword sets with C
bindings, reusable and variant groups, explicit name/reference
namespaces (id<ns>/ref<ns>, following dm_control's
identifier/reference model), child cardinalities, presence constraints
(exclusive/together/requires/oneof over attribute bundles), bitwise
flag sets, identity constants (set field = CONST), fixed char arrays
(chars[n], arity counting characters), numeric range facets, and two
escape hatches: reading=custom (no typed binding is generated; both
reading and saving are hand-written) and writing=custom (the binding
drives the reader, the save policy is hand-written).
doc/generate/mjcf_schema.py is the dependency-free parser and semantic
validator; errors report file:line; 55 unit tests. The language is
documented by the cheat-sheet legend at the top of the schema file.
The schema was bootstrapped by extraction from the sources of record --
the MJCF[] table, the mjMap keyword tables, the ~660 ReadAttr*/MapValue
call sites, mjspec.h struct fields, and the default-constructors in
user_init.c and engine_init.c -- then hand-curated. Same-tag elements
that differ by context are distinct declarations carrying an xml=
facet; worldbody, frame and replicate carry alias=body, mirroring
mjXSchema::NameMatch. The top-level order is by dependency, what a
saved file should read like: front matter, declarations before use,
the tree, the sections that reference it, the data tail.
PiperOrigin-RevId: 958060695
Change-Id: Ie10fd9f0ef202a3626f4d635d02c8731a4d287df
When penetration exceeds a box's smallest half-size, the midpoint
between the contact surfaces can land outside both boxes. The outside-
box filter in mjc_BoxBox then removed every contact of the manifold,
returning nothing for a visibly overlapping pair, letting boxes fall
through each other. Fixes#1800.
If the filter would remove all contacts, restore the penetrating ones.
This is strictly additive: configurations where any contact survives
the filter are unchanged.
The removed midpoints are bitwise-identical to the witness midpoints
computed by mj_geomDistance for these configurations, so the positions
follow the engine-wide contact position convention; re-anchoring them
onto a box surface would not.
Fixes#1800
PiperOrigin-RevId: 957867315
Change-Id: Ia9c858661d4badeb2a832d25455e33402936011d
In the edge-edge path of the box-box collider, when line clipping yields
no points, the corner generators accept points whose projection
parameters are out of range and clamp them into the valid range. The
depth of such a point is the Euclidean distance between two unrelated
points, mixing lateral offset into penetration depth, and on the
penetrating side it is admitted with no margin check. For thin boxes
meeting edge-to-face within margin, this produced a contact with
penetration three orders of magnitude larger than the boxes' true
separation, exploding resting stacks.
No contact can penetrate deeper than the support-interval overlap along
the separating axis, which the SAT stage has already computed. Enforce
this bound on all points emitted by the edge-edge path. The bound
carries margin plus relative and size-scaled slack covering rounding
error: the depth of the deepest legitimate point is algebraically equal
to the bound, so an exact comparison would drop real contacts. The
slack is precision-dependent: in mjUSESINGLE builds the two
computations of the same overlap disagree by tens of ulps, and slack
calibrated for double precision rejects real single-precision contacts.
Differential fuzzing against the nativeccd oracle over 200k random
near-contact thin-box configurations, in both precisions: impossibly
deep contacts drop from 1018 to 4 (worst excess from 2.5x the bounding
diameter to 0.001x), with no legitimate shallow-penetration contact
lost.
PiperOrigin-RevId: 957628830
Change-Id: Iaa1f10742f91c55bf831296cba0936eb50ea09b0
<pid kp kv|dampratio [ki imax] [slewmax]> is a PID controller with real position and velocity setpoint inputs on a single force output, plus an optional feedforward input. With a zero velocity setpoint it reproduces <position> bit-exactly; the input signature is any subset of [pos, vel, ff], selected with input="..." and recorded as mjtCtrlInput bits in
actuator_ctrlspec; absent setpoint inputs are fixed at zero, so the control vector contains no inert entries.
kp and kv are single-sourced in the affine bias parameters (biasprm[1,2]) with no gainprm mirror: every consumer of the position-servo shape
(dampratio conversion, inheritrange, qDeriv) reads one location, which is what makes the bit-exact <position> parity possible. Controller state uses dyntype 'pid' with slot-gated activations in the order [slew, integral], following the dcmotor slot idiom: slewmax (dynprm[1]) rate limits the effective position setpoint through an activation holding it;
ki (gainprm[0]) integrates the position error -- wrapped on rotational transmissions -- with anti-windup clamping of the integrand at imax (dynprm[0]). Both features require the pos input. Servo input unpacking is shared with the dcmotor controller (unpackServoInputs); per-input ranges are exposed as posrange/velrange/ffrange.
This subsumes the functionality of the mujoco.pid plugin with proper activation state: correct under all integrators, visible to keyframes, act sensors and reset. Migration: kp/ki/kd map to kp/ki/kv, plugin imax is in force units (divide by ki), slewmax carries over; the single ctrl becomes input="pos".
PiperOrigin-RevId: 957588898
Change-Id: Id2786836ca6e76f58e5b5cc8323fc23be0a53784
The DC motor's LuGre bristle state must integrate the velocity of its own
transmission, so actuator ordering cannot affect it. The test places a
multi-output SO3 actuator before the DC motor, making the motor's actuator
id and output address diverge, and requires the bristle state to match the
motor-first ordering. Currently fails: the exact ZOH update in
mj_nextActivation reads actuator_velocity[actuator_id] instead of the
motor's own actuator_velocity[outadr], so the bristle integrates the SO3
actuator's velocity.
Every step, the flex block of the implicit effective metric M + K was
factorized by sparse Cholesky, because K depends on the configuration. On
model/flex/bag.xml, added here, that is roughly half the step, against a
comparable share for the constraint solve it exists to accelerate.
Keep only the metric's per-vertex 3x3 diagonal blocks, prefactored. Neither
consumer needs the exact inverse: the CG constraint solver only wants a
preconditioner, and qacc_smooth can come from an iterative solve using those
blocks. They are O(n) to build and to apply, but weaker, so CG runs about twice
the iterations and qacc_smooth becomes an iteration rather than a direct solve.
Net, the bag model steps roughly twice as fast.
The preconditioner, by metric state. Inactive, meaning no flex elasticity or an
explicit integrator: M^-1, unchanged. Bending only (nefmK == 0): M^-1 plus the
exact constant bending factor from mj_setConst on the dofs it covers,
unchanged; that factor is built at model compile time and costs nothing per
step. Per-step stiffness: M^-1 plus the 3x3 blocks, where before it was a
per-step sparse Cholesky, or, when M couples across the flex block, an inner
PCG of up to 50 iterations run once per outer CG iteration.
Only models carrying per-step stretch stiffness change in wall-clock. Both
ponchos hold their timing and take slightly fewer CG iterations than before,
because the preconditioner is now symmetric: it applies M^-1 and the covered
blocks to disjoint sets of dofs, where previously the two overlapped and the
operator was not symmetric, which PCG requires.
mjd_effSolve is the accurate solve of (M + K)x = b; what used to carry that
name only preconditions and is now mjd_effPrec. Its CG guarded the division by
pAp with mjMINVAL, an absolute floor on a quantity that scales with the square
of the right-hand side, so a small b aborted the solve while the curvature was
healthy: four flex models were quietly left short of tolerance. For an SPD
metric the guard is positivity, and with that the same solves converge. The qacc_smooth call site in
mj_fwdAcceleration is textually unchanged but now reaches the iterative solve,
which converges on opt.tolerance rather than a hardcoded threshold, floored in
mjUSESINGLE builds where the squared target is unreachable in float. Reaching
the iteration cap names the ill-conditioned flex stiffness and then reports it
through mjWARN_INERTIA, rather than returning an under-converged result.
Covered dofs are located by walking the covered rows of the stiffness matrix,
as they need not be 3-aligned from dof 0: any joint declared before a flexcomp
shifts them.
mjData.efm_L_rownnz, efm_L_rowadr and efm_L_colind described the sparsity of
the deleted factorization and are removed: left NULL with nonzero mjxmacro
extents they made the Python bindings hand back uninitialized arrays.
efm_active loses the value 2 for the same reason, nothing selects a solve path
on preconditioner exactness any more. Both are recorded under breaking changes.
model/flex/bag.xml is added because no shipped model carried per-step stretch
stiffness. The ponchos are bending-only and trampoline.xml uses an explicit
integrator, so the metric never activates there. It is excluded from
WriteReadCompareTest: stretch stiffness amplifies rest geometry that XML rounds
on save.
The implicit effective metric assembles the stretch stiffness from
world-space edge vectors, but a flex vertex body's slide dofs are
expressed in its parent body's frame. When that frame is rotated the
assembled operator is therefore not the Jacobian of the passive stretch
force, which mj_flexPassiveStretch already maps into the dof frame with
xmat^T. The metric is then inconsistent with the force it linearizes:
implicit integration loses its stability guarantee, and models that the
same flex handles comfortably in an unrotated frame diverge.
Apply the matching change of basis in both places that build or apply the
stretch stiffness: mjd_flexStretch_mul rotates the input dof vector into
world and the scattered result back, and mjd_flexStiff_assemble sandwiches
each 3x3 block as R_bi^T * blk * R_bj. Both are no-ops when the parent is
unrotated. Bending needs no change: its blocks are isotropic, and
R^T (q I) R = q I.
This completes the fix in fe9dc584, which covered the passive force paths
and the interp (trilinear) derivative but not the standard stretch one.
On a mesh flex inside a body with a 90-degree rotation, the metric's
directional agreement with the force Jacobian goes from cos = 0.57 to
cos = 1.0, and a hanging sheet that previously reached 176% strain
settles at 0.87%.
Fast path in mj_flexPassiveInterp, mj_flexPassiveBendInterp, and
mj_flexPassiveStretch assumed body slide joints are world-aligned
(J = I). When parent body has a non-identity quaternion, joint axes
are rotated (J = R_body), causing wrong force mapping and instability
(NaN/Inf in QACC).
Fix: project world-frame forces onto body local frame via
mju_mulMatTVec3(R_body^T, force) before adding to qfrc_spring/damper.
Also fix the derivative paths:
- mjd_flexInterp_kernel fast path: R^T * K_rot * R * vec
- mjd_flexStiff_assemble (CSR): R_bi^T * K_rot_block * R_bj
The CSR-assembled stiffness matrix is the actual path used by the
implicit CG solver (mj_flexCG gate). The test uses solver="CG" to
activate this path; without it, flex stiffness is integrated
explicitly and no derivative fix can help.
Ported from GitHub PR https://github.com/google-deepmind/mujoco/pull/3379
Original author: Devansh (https://github.com/devansh0703)
Fixes https://github.com/google-deepmind/mujoco/issues/3364
PiperOrigin-RevId: 952789284
Change-Id: If924f7160dd16c0cc88170d80e6e605da0fe2e04
https://youtu.be/17XpwnqyCXs
New transmission type mjTRN_SO3: a relative orientation, targeting a ball
joint or a site+refsite pair. It is the first transmission with more than
one force output: its length is the norm of the expmap vector of the
relative rotation and its moment axes are the 3 rows of the
relative rotational Jacobian, without projecting onto per-actuator gears.
New force law mjGAIN_SO3/mjBIAS_SO3: a geodesic PD servo, force =
kp * log(q_current^-1 * q_target) - kv * velocity, exact for arbitrary axis
combinations with a unique equilibrium at every commanded orientation.
Error, moment rows and velocity all live in the child frame (joint or
site): the right-difference error is the gradient of the geodesic
potential in that frame. The parent-frame (left) error is not: driving
child-frame torques with it pumps energy at large angles, settling into
steady-spinning limit cycles (the SO3LargeAngleConvergence test). The
integrator variant stores the 3D orientation setpoint in act (actnum = 3,
re-anchored to a bounded representative at integration time). Exposed in
MJCF as <orientation joint=|site=+refsite= kp kv|dampratio>, or via
<general gaintype="so3" biastype="so3">.
The setpoint input has two charts: an expmap target (3 controls, default)
or a quaternion target (4 controls) -- <orientation input="quat">, the
first actuator with different input and output widths. The signature is
recorded in a new per-actuator field actuator_ctrlspec (mjtCtrlChart),
whose meaning is scoped by the gain type the way gain/bias parameters are;
ctrlnum is derived from it at compile time and remains the layout
authority. An explicit field rather than width inference or a prm slot:
width-as-chart cannot express same-width signatures (upcoming servo input
subsets), and prm slots are the input_mode pattern this stack retires.
The force law normalizes the commanded quaternion, making it scale- and
antipodally-invariant. The all-zero ctrl still maps to the identity via
mju_normalize4, but it is a degenerate point (a nudge of any component
commands a half-turn), so quat inputs reset to the identity quaternion:
new mj_resetCtrl sets neutral ctrl values (zero, except qw = 1), called
by mj_resetData and the viewers' Clear All. The quat chart is
restricted to dyntype 'none': integrating a quaternion setpoint linearly
is not meaningful on the manifold. New mjsActuator.ctrlspec field carries
the signature through the spec and XML round-trip.
Actuator sensors (actuatorpos/vel/frc) now report one value per force
output; dim = 3 on an SO3 actuator.
As the first actuator with nu != nactuator, this commit also makes the
viewers multi-input aware: the control sliders in simulate and studio,
which indexed per-actuator arrays by control index (out of bounds on
this model class), are generated per control and labeled with the
actuator name plus an input suffix ("orient/qw"), via the new
introspection helper mj_actuatorInputName -- the single source of truth
for input names, extended by each new multi-input type (quaternion
components are w-first: qw, qx, qy, qz). Slider ranges now honor a
defined ctrlrange even when ctrllimited is false: range is the UI hint,
limited is the clamp -- wrapped and expmap setpoints are unbounded but
still want finite sliders, while quat components are truly bounded.
The rotational demo model is orientation.xml under
test/engine/testdata/actuation/, upgraded to a three-way contrast:
per-axis wrapped servos vs an expmap-commanded vs a quat-commanded
orientation actuator, on identical checker-textured boxes. It is loaded
by the mixed-axis contrast and input-name tests, and doubles as the
viewer test model (slider groups of 3 independent, 3 grouped, 4 grouped).
PiperOrigin-RevId: 951607063
Change-Id: If235dba8e2f2ca72672e7c62531a27e967c6a373
Store island topology in `mjData` so repeated island solves can reuse stable connect/weld equality partitions. Add cache invalidation checks for active equality changes and cover the fast path with an island regression test.
Signed-off-by: teerthsharma <teerths57@gmail.com>
https://youtu.be/GioWwB36XHI
The new geom attribute adhesion (units of force, signed; pair-level
override) translates the contact friction cone along its normal so
that the force origin lies strictly inside it. Consequences: each
contact can pull with up to the given force before breaking, and the
tangential friction budget becomes mu*(f_N + adhesion) -- the
Mohr-Coulomb yield condition with cohesion c = mu*adhesion -- so
lightly-squeezed grasps retain a guaranteed friction floor.
A translated cone factors exactly into {constant attractive force}
+ {original cone}, so no solver kernels change. The implementation is
this factorization: a constant attraction along contact normals
accumulated into the new mjData.qfrc_adhesion (summed into
qfrc_passive), plus a bias of adhesive contact rows' reference
acceleration (aref += R*adhesion), which makes resting penetration
exactly independent of adhesion. Contacts of adhesive pairs remain
active throughout the gap zone, producing rows with positive violation
whose reference acceleration pulls: a tether that resists pull-off
smoothly, captures objects released within the band into steady
contact, and detaches at the specified force. Adhesion values of the
two geoms combine by sum; explicit pairs override.
mj_contactForce reports the net interface force (cone force minus the
adhesive pull), whose normal component can now be negative. Negative
adhesion is allowed and produces a repulsive offset (air hockey).
PiperOrigin-RevId: 950858148
Change-Id: I879c08eba7ae501e5c0f8c2f807167344da4c2bc
- Wrapping in force path is local; act is re-anchored at integration time.
- Remove hardcoded `actrange` for intvelocity actuators.
PiperOrigin-RevId: 949566477
Change-Id: I349fdf17eedfbb2174d698cc1a6a91d52810b4a3
Sam Haves