ex_pick Namespace Reference

Classes
class	ResetRequested
class	Phase

Functions
mjk.AttachmentSpec	gripper_attachment (str gripper_path)
mjk.SceneObject	cube_object ()
tuple[mjk.Env, mjk.Robot]	build_env ()
kdl.JntArray	jnt (list[float] values)
list[float]	as_list (kdl.JntArray q)
float	clamp (float value, float low, float high)
float	clamp_joint (float value, tuple[float, float] limit)
list[float]	solve_position_ik (kdl.Chain chain, list[float] seed_values, kdl.Frame target, list[tuple[float, float]] joint_limits)
dict[str, list[float]]	build_waypoints (mjk.Env env, mjk.Robot robot)
None	apply_pd_gravity (mjk.Robot robot, list[float] target)
float	max_abs_joint_err (mjk.Robot robot, list[float] target)
list[float]	lerp (list[float] start, list[float] target, float alpha)
bool	step_once (mjk.Env env, mjk.Robot robot, mjk.SimulateViewer|None viewer, dict state)
bool	run_phase (mjk.Env env, mjk.Robot robot, Phase phase, mjk.SimulateViewer|None viewer, dict state)
int	main ()

Variables
list	HOME = [0.0, 0.2618, 3.1416, -2.2689, 0.0, 0.9599, 1.5708]
float	CUBE_X = 0.40
float	CUBE_Y = 0.00
float	CUBE_HALF_SIZE = 0.02
float	CUBE_Z = CUBE_HALF_SIZE
list	KP = [100.0, 200.0, 100.0, 200.0, 100.0, 200.0, 100.0]
list	KD = [10.0, 20.0, 10.0, 20.0, 10.0, 20.0, 10.0]

Detailed Description

Scripted floor pick example ported from src/examples/ex_pick.cpp.

Joint-impedance control (tau = Kp*e - Kd*qdot + g_kdl) drives scripted
waypoints to grasp and lift a cube. An Env on_reset hook re-homes the arm,
re-poses the cube, and opens the gripper, so the simulate-UI reset button
replays the whole pick.

Function Documentation

apply_pd_gravity()

None ex_pick.apply_pd_gravity	(	mjk.Robot	robot,
		list[float]	target )

Definition at line 159 of file ex_pick.py.

Referenced by run_phase().

as_list()

list[float] ex_pick.as_list

(

kdl.JntArray

q

)

Definition at line 94 of file ex_pick.py.

Referenced by solve_position_ik().

build_env()

tuple[mjk.Env, mjk.Robot] ex_pick.build_env

(

)

Definition at line 63 of file ex_pick.py.

References cube_object(), and gripper_attachment().

Referenced by main().

build_waypoints()

dict[str, list[float]] ex_pick.build_waypoints	(	mjk.Env	env,
		mjk.Robot	robot )

Definition at line 139 of file ex_pick.py.

References solve_position_ik().

Referenced by main().

clamp()

float ex_pick.clamp	(	float	value,
		float	low,
		float	high )

Definition at line 98 of file ex_pick.py.

Referenced by clamp_joint(), and run_phase().

clamp_joint()

float ex_pick.clamp_joint	(	float	value,
		tuple[float, float]	limit )

Definition at line 102 of file ex_pick.py.

References clamp().

Referenced by solve_position_ik().

cube_object()

mjk.SceneObject ex_pick.cube_object

(

)

Definition at line 50 of file ex_pick.py.

Referenced by build_env().

gripper_attachment()

mjk.AttachmentSpec ex_pick.gripper_attachment

(

str

gripper_path

)

Definition at line 42 of file ex_pick.py.

Referenced by build_env().

jnt()

kdl.JntArray ex_pick.jnt

(

list[float]

values

)

Definition at line 87 of file ex_pick.py.

Referenced by solve_position_ik().

lerp()

list[float] ex_pick.lerp	(	list[float]	start,
		list[float]	target,
		float	alpha )

Definition at line 172 of file ex_pick.py.

Referenced by run_phase().

main()

int ex_pick.main

(

)

Definition at line 219 of file ex_pick.py.

References build_env(), build_waypoints(), main(), and run_phase().

Referenced by main().

max_abs_joint_err()

float ex_pick.max_abs_joint_err	(	mjk.Robot	robot,
		list[float]	target )

Definition at line 168 of file ex_pick.py.

Referenced by run_phase().

run_phase()

bool ex_pick.run_phase	(	mjk.Env	env,
		mjk.Robot	robot,
		Phase	phase,
		mjk.SimulateViewer | None	viewer,
		dict	state )

Definition at line 190 of file ex_pick.py.

References apply_pd_gravity(), clamp(), lerp(), max_abs_joint_err(), and step_once().

Referenced by main().

solve_position_ik()

list[float] ex_pick.solve_position_ik	(	kdl.Chain	chain,
		list[float]	seed_values,
		kdl.Frame	target,
		list[tuple[float, float]]	joint_limits )

Definition at line 109 of file ex_pick.py.

References as_list(), clamp_joint(), and jnt().

Referenced by build_waypoints().

step_once()

bool ex_pick.step_once	(	mjk.Env	env,
		mjk.Robot	robot,
		mjk.SimulateViewer | None	viewer,
		dict	state )

Definition at line 176 of file ex_pick.py.

Referenced by run_phase().

Variable Documentation

CUBE_HALF_SIZE

float ex_pick.CUBE_HALF_SIZE = 0.02

Definition at line 22 of file ex_pick.py.

CUBE_X

float ex_pick.CUBE_X = 0.40

Definition at line 20 of file ex_pick.py.

CUBE_Y

float ex_pick.CUBE_Y = 0.00

Definition at line 21 of file ex_pick.py.

CUBE_Z

float ex_pick.CUBE_Z = CUBE_HALF_SIZE

Definition at line 23 of file ex_pick.py.

HOME

list ex_pick.HOME = [0.0, 0.2618, 3.1416, -2.2689, 0.0, 0.9599, 1.5708]

Definition at line 19 of file ex_pick.py.

KD

list ex_pick.KD = [10.0, 20.0, 10.0, 20.0, 10.0, 20.0, 10.0]

Definition at line 25 of file ex_pick.py.

KP

list ex_pick.KP = [100.0, 200.0, 100.0, 200.0, 100.0, 200.0, 100.0]

Definition at line 24 of file ex_pick.py.