Commit Graph
3 Commits
Author SHA1 Message Date
cristhian d336f8d499 read the gamepad from dora-joy and publish twist and command
The pad moves to dora-joy, so this node keeps no hardware dependency and the
pad becomes reusable. It arrives on `joy` as a plain reading; `JoyInput.read`
treats silence past JOY_TTL_S as absence, because that node dying looks like
silence rather than like an unplugged pad and the arm cannot tell them apart.

Both control sources are now normalised to a [-1, 1] six-vector before anything
is scaled, and the scaling happens in one function. The web path used to pass a
velocity straight through without going near mapping, which is why the console
had to speak the arm's units. It no longer does.

`twist` (SI) and `command` (robot-agnostic verbs) are the standard ports. `jog`
and `request` still carry the same intent in dora-ulite6's units and service
names so the two repositories can move independently; LEGACY_REQUEST is the
only place that knows what that node calls a verb. Wire one or the other, never
both. `joint_jog` is specified in the manifest and deliberately not built.

Schemas are declared rather than inferred: pyarrow reads a null `value` as its
own type, so an inferred `command` would change its port's type between one
verb and the next.

Three bugs found while moving this code, each with a test:

- `Sample.active` compared raw axes against a threshold, but SDL rests a
  trigger at -1.0, so every connected pad read as in use for ever: the pad took
  the lease on plug-in and GAMEPAD_IDLE_RELEASE_S never fired.
- The e-stop latch was never consulted when deciding a velocity, so Back
  stopped the arm for one tick and the next stick nudge drove it again. Nothing
  on the pad could clear it either. It is now checked above the lease, and X
  releases it and clears the controller's error, as the console's RESET does.
- Buttons were read before the arbiter granted the lease, so the first press
  after the pad had been idle was swallowed: not owned yet when read, and no
  longer a rising edge by the next tick.
2026-09-16 12:18:51 -05:00
cristhian 8a7bfb02e0 add a probe that shows what the gamepad is doing
validate / validate (pull_request) Failing after 58m47s
validate / test (pull_request) Successful in 58m48s
validate / markdownlint (pull_request) Successful in 58m43s
The axis and button indices in mapping.py are SDL's documented layout rather
than an observed one, and until now the only way to find a pad that numbers
things differently was to watch a real arm move the wrong way.

`dora-teleop-probe` prints the raw axes, the buttons it sees and the velocity
that would be sent, live, with no dataflow and no arm — it cannot move anything.
It goes through the same Gamepad and velocity() the node runs, so what it prints
is what the arm would get; that is the whole reason it is worth having, and the
reason it must not grow its own copy of the mapping.

Every axis is listed, including ones the layout does not use, because an axis
marked unused that moves when a stick is pushed is exactly the finding this is
for. The centred bar makes a worn stick that does not return to zero obvious.
2026-09-15 15:47:36 -05:00
cristhian bde8582de3 add the gamepad reader and the node's settings
The reader owns the pad on a thread of its own, and nothing outside that file
may touch pygame: everything else sees a plain immutable Sample. That is what
lets the rest of the node be tested with no hardware, and what keeps SDL's
quirks out of the arm logic.

Sample.present is the field that matters. A pad that has been unplugged reads as
absent rather than as centred, so "the operator let go" and "the pad fell off
the desk" stay distinguishable — they call for the same stop, but only one of
them is worth logging.

Only the display and joystick subsystems are initialised. pygame.init() also
opens audio, which on a headless robot fills stderr with ALSA errors for a
device this node never uses; the display is needed despite there being no
window, because SDL refreshes joystick state during the event pump.

Settings are parsed once at startup so a deadzone that would silently make the
pad inert stops the node before it joins the dataflow.
2026-09-15 15:42:48 -05:00