arm_trajectories Namespace Reference

Classes
class	CartesianTajectory
class	ForceTrajectory
class	JointTrajectory
Functions
def	compute_forces
	compute the force that the arm would apply given the stiffness matrix
def	compute_radial_tangential_forces
	return two lists containing the radial and tangential components of the forces.
def	compute_workspace
def	compute_workspace_z
def	diff_roll_angles
def	fit_circle
	find the x and y coord of the center of the circle and the radius that best matches the data.
def	fit_rotary_joint
	find the x and y coord of the center of the circle of given radius that best matches the data.
def	joint_to_cartesian
def	plot_cartesian
def	plot_error_forces
def	plot_forces_quiver
def	plot_stiff_ellipse_map
def	plot_stiff_ellipses
def	plot_stiffness_field
Variables
tuple	actual_cartesian = joint_to_cartesian(d['actual'])
tuple	angle = math.atan2(y_diff,x_diff)
list	arm_stiffness_list = d['stiffness']
list	asl = [min(scale*s,1.0) for s in arm_stiffness_list]
tuple	ax = pl.gca()
string	color = 'k'
tuple	curr_size = f.get_size_inches()
tuple	d = ut.load_pickle(fname)
list	ee_start_pos = pts_list[0]
tuple	end_angle = tr.angle_within_mod180(math.atan2(end_pt[1,0],end_pt[0,0])-math.radians(90))
list	end_pt = pts2d_actual_t[:,-1]
tuple	eq_cartesian = joint_to_cartesian(d['eq_pt'])
	expt_plot = opt.exptplot
tuple	f = pl.gcf()
list	fig_name = str_parts[0]
	fname = opt.fname
tuple	force_mag = ut.norm(forces)
list	force_traj = d['force']
tuple	forces = np.matrix(force_traj.f_list)
string	help = 'pkl file to use.'
int	i = 0
tuple	leg = pl.legend(loc='best')
tuple	p = optparse.OptionParser()
	p_list = actual_cartesian.p_list
	plot_ellipses_flag = opt.plot_ellipses
	plot_ellipses_vary_flag = opt.pev
	plot_force_components_flag = opt.pfc
	plot_force_field_flag = opt.pff
	plot_forces_error_flag = opt.plot_forces_error
	plot_forces_flag = opt.plot_forces
	plot_mechanism_frame = opt.pmf
	plot_workspace_flag = opt.pwf
tuple	pts2d_actual = (np.matrix(actual_cartesian.p_list).T)
tuple	pts2d_actual_t = rot_mat*(pts2d_actual - translation_mat)
tuple	pts_2d = (np.matrix(pts_list).T)
	pts_list = actual_cartesian.p_list
	rad = opt.rad
	rad_fix = opt.rad_fix
float	rad_guess = 0.9
list	ratio_list1 = [0.1,0.3,0.5,0.7,0.9]
list	ratio_list2 = [0.1,0.3,0.5,0.7,0.9]
list	ratio_list3 = [0.1,0.3,0.5,0.7,0.9]
tuple	robot_mat = rot_mat*(np.matrix([robot_x_list,robot_y_list]) - translation_mat)
list	robot_x_list = [-robot_width/2,-robot_width/2,robot_width/2,robot_width/2,-robot_width/2]
list	robot_y_list = [-robot_length/2,robot_length/2,robot_length/2,-robot_length/2,-robot_length/2]
tuple	rot_mat = tr.Rz(angle)
float	s0 = 0.2
list	s_list = [s0,s1,s2,s3,0.8]
list	s_scale = d['stiffness']
list	scale = d['stiffness']
tuple	show_fig = not(opt.noshow)
list	sl = [min(s*s_scale,1.0) for s in s_list]
list	st_pt = pts_2d[:,0]
tuple	start_angle = tr.angle_within_mod180(math.atan2(st_pt[1,0]-cy,st_pt[0,0]-cx) - math.radians(90))
list	start_pt = actual_cartesian.p_list[0]
tuple	str_parts = fname.split('.')
int	subplotnum = 234
tuple	t0 = time.time()
tuple	t1 = time.time()
tuple	t2 = time.time()
list	time_dict = d['time_dict']
list	time_list = d['force']
tuple	translation_mat = np.matrix([cx,cy])
tuple	x_coord_list = np.matrix(p_list)
list	x_diff = start_pt[0]
list	x_guess = ee_start_pos[0]
	xy_flag = opt.xy
	xyz_flag = opt.xyz
	xz_flag = opt.xz
list	y_diff = start_pt[1]
list	y_guess = ee_start_pos[1]
	yz_flag = opt.yz

---

Function Documentation

def arm_trajectories.compute_forces	(		q_actual_traj,
			q_eq_traj,
			torque_traj,
			rel_stiffness_list
	)

compute the force that the arm would apply given the stiffness matrix

Parameters:

q_actual_traj	- Joint Trajectory (actual angles.)
q_eq_traj	- Joint Trajectory (equilibrium point angles.)
torque_traj	- JointTrajectory (torques measured at the joints.)
rel_stiffness_list	- list of 5 elements (stiffness numbers for the joints.)

Returns:

lots of things, look at the code.

Definition at line 162 of file arm_trajectories.py.

def arm_trajectories.compute_radial_tangential_forces	(		f_list,
			p_list,
			cx,
			cy
	)

return two lists containing the radial and tangential components of the forces.

Parameters:

f_list	- list of forces. (each force is a list of 2 or 3 floats)
p_list	- list of positions. (each position is a list of 2 or 3 floats)
cx	- x coord of the center of the circle.
cy	- y coord of the center of the circle.

Returns:

list of magnitude of radial component, list of magnitude tangential component.

Definition at line 218 of file arm_trajectories.py.

def arm_trajectories.compute_workspace	(		z,
			plot = False,
			wrist_roll_angle = math.radians(0),
			subplotnum = None,
			title = ''
	)

Definition at line 437 of file arm_trajectories.py.

def arm_trajectories.compute_workspace_z

(

)

Definition at line 473 of file arm_trajectories.py.

def arm_trajectories.diff_roll_angles

(

)

Definition at line 468 of file arm_trajectories.py.

def arm_trajectories.fit_circle	(		rad_guess,
			x_guess,
			y_guess,
			pts,
			method,
			verbose = True
	)

find the x and y coord of the center of the circle and the radius that best matches the data.

Parameters:

rad_guess	- guess for the radius of the circle
x_guess	- guess for x coord of center
y_guess	- guess for y coord of center.
pts	- 2xN np matrix of points.
method	- optimization method. ('fmin' or 'fmin_bfgs')
verbose	- passed onto the scipy optimize functions. whether to print out the convergence info.

Returns:

r,x,y (radius, x and y coord of the center of the circle)

Definition at line 546 of file arm_trajectories.py.

def arm_trajectories.fit_rotary_joint	(		rad,
			x_guess,
			y_guess,
			pts
	)

find the x and y coord of the center of the circle of given radius that best matches the data.

Parameters:

rad	- radius of the circle (not optimized)
x_guess	- guess for x coord of center
y_guess	- guess for y coord of center.
pts	- 2xN np matrix of points.

Returns:

x,y (x and y coord of the center of the circle)

Definition at line 514 of file arm_trajectories.py.

def arm_trajectories.joint_to_cartesian

(

traj

)

traj - JointTrajectory
    returns CartesianTajectory after performing FK on traj.

Definition at line 75 of file arm_trajectories.py.

def arm_trajectories.plot_cartesian	(		traj,
			xaxis = None,
			yaxis = None,
			zaxis = None,
			color = 'b',
			label = '_nolegend_',
			linewidth = 2,
			scatter_size = 20
	)

xaxis - x axis for the graph (0,1 or 2)
    zaxis - for a 3d plot. not implemented.

Definition at line 110 of file arm_trajectories.py.

def arm_trajectories.plot_error_forces	(		measured_list,
			calc_list
	)

Definition at line 233 of file arm_trajectories.py.

def arm_trajectories.plot_forces_quiver	(		pos_traj,
			force_traj,
			color = 'k'
	)

Definition at line 92 of file arm_trajectories.py.

def arm_trajectories.plot_stiff_ellipse_map	(		stiffness_list,
			num
	)

Definition at line 389 of file arm_trajectories.py.

def arm_trajectories.plot_stiff_ellipses	(		k_cart_list,
			pos_traj,
			skip = 10,
			subplotnum = 111
	)

Definition at line 307 of file arm_trajectories.py.

def arm_trajectories.plot_stiffness_field	(		k_cart,
			plottitle = ''
	)

Parameters:

k_cart,:

3x3 cartesian space stiffness matrix.

Definition at line 361 of file arm_trajectories.py.

---

Variable Documentation

tuple arm_trajectories::actual_cartesian = joint_to_cartesian(d['actual'])

Definition at line 691 of file arm_trajectories.py.

tuple arm_trajectories::angle = math.atan2(y_diff,x_diff)

Definition at line 739 of file arm_trajectories.py.

list arm_trajectories::arm_stiffness_list = d['stiffness']

Definition at line 829 of file arm_trajectories.py.

list arm_trajectories::asl = [min(scale*s,1.0) for s in arm_stiffness_list]

Definition at line 831 of file arm_trajectories.py.

tuple arm_trajectories::ax = pl.gca()

Definition at line 811 of file arm_trajectories.py.

string arm_trajectories::color = 'k'

Definition at line 748 of file arm_trajectories.py.

tuple arm_trajectories::curr_size = f.get_size_inches()

Definition at line 883 of file arm_trajectories.py.

tuple arm_trajectories::d = ut.load_pickle(fname)

Definition at line 690 of file arm_trajectories.py.

list arm_trajectories::ee_start_pos = pts_list[0]

Definition at line 703 of file arm_trajectories.py.

tuple arm_trajectories::end_angle = tr.angle_within_mod180(math.atan2(end_pt[1,0],end_pt[0,0])-math.radians(90))

Definition at line 755 of file arm_trajectories.py.

list arm_trajectories::end_pt = pts2d_actual_t[:,-1]

Definition at line 754 of file arm_trajectories.py.

tuple arm_trajectories::eq_cartesian = joint_to_cartesian(d['eq_pt'])

Definition at line 692 of file arm_trajectories.py.

arm_trajectories::expt_plot = opt.exptplot

Definition at line 636 of file arm_trajectories.py.

tuple arm_trajectories::f = pl.gcf()

Definition at line 882 of file arm_trajectories.py.

list arm_trajectories::fig_name = str_parts[0]

Definition at line 764 of file arm_trajectories.py.

arm_trajectories::fname = opt.fname

Definition at line 622 of file arm_trajectories.py.

tuple arm_trajectories::force_mag = ut.norm(forces)

Definition at line 817 of file arm_trajectories.py.

list arm_trajectories::force_traj = d['force']

Definition at line 815 of file arm_trajectories.py.

tuple arm_trajectories::forces = np.matrix(force_traj.f_list)

Definition at line 816 of file arm_trajectories.py.

string arm_trajectories::help = 'pkl file to use.'

Definition at line 587 of file arm_trajectories.py.

int arm_trajectories::i = 0

Definition at line 648 of file arm_trajectories.py.

tuple arm_trajectories::leg = pl.legend(loc='best')

Definition at line 808 of file arm_trajectories.py.

tuple arm_trajectories::p = optparse.OptionParser()

Definition at line 585 of file arm_trajectories.py.

arm_trajectories::p_list = actual_cartesian.p_list

Definition at line 853 of file arm_trajectories.py.

arm_trajectories::plot_ellipses_flag = opt.plot_ellipses

Definition at line 627 of file arm_trajectories.py.

arm_trajectories::plot_ellipses_vary_flag = opt.pev

Definition at line 635 of file arm_trajectories.py.

arm_trajectories::plot_force_components_flag = opt.pfc

Definition at line 629 of file arm_trajectories.py.

arm_trajectories::plot_force_field_flag = opt.pff

Definition at line 630 of file arm_trajectories.py.

arm_trajectories::plot_forces_error_flag = opt.plot_forces_error

Definition at line 628 of file arm_trajectories.py.

arm_trajectories::plot_forces_flag = opt.plot_forces

Definition at line 626 of file arm_trajectories.py.

arm_trajectories::plot_mechanism_frame = opt.pmf

Definition at line 631 of file arm_trajectories.py.

arm_trajectories::plot_workspace_flag = opt.pwf

Definition at line 638 of file arm_trajectories.py.

tuple arm_trajectories::pts2d_actual = (np.matrix(actual_cartesian.p_list).T)

Definition at line 750 of file arm_trajectories.py.

tuple arm_trajectories::pts2d_actual_t = rot_mat*(pts2d_actual - translation_mat)

Definition at line 751 of file arm_trajectories.py.

tuple arm_trajectories::pts_2d = (np.matrix(pts_list).T)

Definition at line 707 of file arm_trajectories.py.

arm_trajectories::pts_list = actual_cartesian.p_list

Definition at line 702 of file arm_trajectories.py.

arm_trajectories::rad = opt.rad

Definition at line 633 of file arm_trajectories.py.

arm_trajectories::rad_fix = opt.rad_fix

Definition at line 637 of file arm_trajectories.py.

arm_trajectories::rad_guess = 0.9

Definition at line 711 of file arm_trajectories.py.

list arm_trajectories::ratio_list1 = [0.1,0.3,0.5,0.7,0.9]

Definition at line 649 of file arm_trajectories.py.

list arm_trajectories::ratio_list2 = [0.1,0.3,0.5,0.7,0.9]

Definition at line 650 of file arm_trajectories.py.

list arm_trajectories::ratio_list3 = [0.1,0.3,0.5,0.7,0.9]

Definition at line 651 of file arm_trajectories.py.

tuple arm_trajectories::robot_mat = rot_mat*(np.matrix([robot_x_list,robot_y_list]) - translation_mat)

Definition at line 746 of file arm_trajectories.py.

list arm_trajectories::robot_x_list = [-robot_width/2,-robot_width/2,robot_width/2,robot_width/2,-robot_width/2]

Definition at line 744 of file arm_trajectories.py.

list arm_trajectories::robot_y_list = [-robot_length/2,robot_length/2,robot_length/2,-robot_length/2,-robot_length/2]

Definition at line 745 of file arm_trajectories.py.

tuple arm_trajectories::rot_mat = tr.Rz(angle)

Definition at line 740 of file arm_trajectories.py.

float arm_trajectories::s0 = 0.2

Definition at line 661 of file arm_trajectories.py.

list arm_trajectories::s_list = [s0,s1,s2,s3,0.8]

Definition at line 667 of file arm_trajectories.py.

list arm_trajectories::s_scale = d['stiffness']

Definition at line 777 of file arm_trajectories.py.

list arm_trajectories::scale = d['stiffness']

Definition at line 830 of file arm_trajectories.py.

arm_trajectories::show_fig = not(opt.noshow)

Definition at line 634 of file arm_trajectories.py.

list arm_trajectories::sl = [min(s*s_scale,1.0) for s in s_list]

Definition at line 778 of file arm_trajectories.py.

list arm_trajectories::st_pt = pts_2d[:,0]

Definition at line 791 of file arm_trajectories.py.

tuple arm_trajectories::start_angle = tr.angle_within_mod180(math.atan2(st_pt[1,0]-cy,st_pt[0,0]-cx) - math.radians(90))

Definition at line 792 of file arm_trajectories.py.

list arm_trajectories::start_pt = actual_cartesian.p_list[0]

Definition at line 736 of file arm_trajectories.py.

tuple arm_trajectories::str_parts = fname.split('.')

Definition at line 763 of file arm_trajectories.py.

int arm_trajectories::subplotnum = 234

Definition at line 842 of file arm_trajectories.py.

tuple arm_trajectories::t0 = time.time()

Definition at line 708 of file arm_trajectories.py.

tuple arm_trajectories::t1 = time.time()

Definition at line 715 of file arm_trajectories.py.

tuple arm_trajectories::t2 = time.time()

Definition at line 717 of file arm_trajectories.py.

list arm_trajectories::time_dict = d['time_dict']

Definition at line 781 of file arm_trajectories.py.

list arm_trajectories::time_list = d['force']

Definition at line 860 of file arm_trajectories.py.

tuple arm_trajectories::translation_mat = np.matrix([cx,cy])

Definition at line 741 of file arm_trajectories.py.

tuple arm_trajectories::x_coord_list = np.matrix(p_list)

Definition at line 862 of file arm_trajectories.py.

list arm_trajectories::x_diff = start_pt[0]

Definition at line 737 of file arm_trajectories.py.

list arm_trajectories::x_guess = ee_start_pos[0]

Definition at line 704 of file arm_trajectories.py.

arm_trajectories::xy_flag = opt.xy

Definition at line 623 of file arm_trajectories.py.

arm_trajectories::xyz_flag = opt.xyz

Definition at line 632 of file arm_trajectories.py.

arm_trajectories::xz_flag = opt.xz

Definition at line 625 of file arm_trajectories.py.

list arm_trajectories::y_diff = start_pt[1]

Definition at line 738 of file arm_trajectories.py.

list arm_trajectories::y_guess = ee_start_pos[1]

Definition at line 705 of file arm_trajectories.py.

arm_trajectories::yz_flag = opt.yz

Definition at line 624 of file arm_trajectories.py.