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minor changes

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Takayuki Murooka
2019-01-26 03:06:27 +09:00
parent b543623cad
commit 33e7b67db0
2 changed files with 11 additions and 11 deletions
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21
ArmNavigation/n_joint_arm_3d/NLinkArm.py
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@@ -24,11 +24,11 @@ class Link:
return trans
def basic_jacobian(self, trans_prev, ee_pose):
def basic_jacobian(self, trans_prev, ee_pos):
pos_prev = np.array([trans_prev[0, 3], trans_prev[1, 3], trans_prev[2, 3]])
z_axis_prev = np.array([trans_prev[0, 2], trans_prev[1, 2], trans_prev[2, 2]])
basic_jacobian = np.hstack((np.cross(z_axis_prev, ee_pose - pos_prev), z_axis_prev))
basic_jacobian = np.hstack((np.cross(z_axis_prev, ee_pos - pos_prev), z_axis_prev))
return basic_jacobian
@@ -50,7 +50,7 @@ class NLinkArm:
x = trans[0, 3]
y = trans[1, 3]
z = trans[2, 3]
alpha, beta, gamma = self.calc_euler_angle()
alpha, beta, gamma = self.euler_angle()
if plot:
self.fig = plt.figure()
@@ -82,12 +82,13 @@ class NLinkArm:
return [x, y, z, alpha, beta, gamma]
def basic_jacobian(self, ee_pose):
def basic_jacobian(self):
ee_pos = self.forward_kinematics()[0:3]
basic_jacobian_mat = []
trans = np.identity(4)
for i in range(len(self.link_list)):
basic_jacobian_mat.append(self.link_list[i].basic_jacobian(trans, ee_pose[0:3]))
basic_jacobian_mat.append(self.link_list[i].basic_jacobian(trans, ee_pos))
trans = np.dot(trans, self.link_list[i].transformation_matrix())
return np.array(basic_jacobian_mat).T
@@ -97,8 +98,8 @@ class NLinkArm:
ee_pose = self.forward_kinematics()
diff_pose = np.array(ref_ee_pose) - ee_pose
basic_jacobian_mat = self.basic_jacobian(ee_pose)
alpha, beta, gamma = self.calc_euler_angle()
basic_jacobian_mat = self.basic_jacobian()
alpha, beta, gamma = self.euler_angle()
K_zyz = np.array([[0, -math.sin(alpha), math.cos(alpha) * math.sin(beta)],
[0, math.cos(alpha), math.sin(alpha) * math.sin(beta)],
@@ -138,13 +139,13 @@ class NLinkArm:
self.ax.plot([ref_ee_pose[0]], [ref_ee_pose[1]], [ref_ee_pose[2]], "o")
plt.show()
def calc_euler_angle(self):
def euler_angle(self):
trans = self.transformation_matrix()
alpha = math.atan2(trans[1][2], trans[0][2])
if -math.pi / 2 <= alpha and alpha <= math.pi / 2:
if not (-math.pi / 2 <= alpha and alpha <= math.pi / 2):
alpha = math.atan2(trans[1][2], trans[0][2]) + math.pi
if -math.pi / 2 <= alpha and alpha <= math.pi / 2:
if not (-math.pi / 2 <= alpha and alpha <= math.pi / 2):
alpha = math.atan2(trans[1][2], trans[0][2]) - math.pi
beta = math.atan2(trans[0][2] * math.cos(alpha) + trans[1][2] * math.sin(alpha), trans[2][2])
gamma = math.atan2(-trans[0][0] * math.sin(alpha) + trans[1][0] * math.cos(alpha), -trans[0][1] * math.sin(alpha) + trans[1][1] * math.cos(alpha))

1
ArmNavigation/n_joint_arm_3d/random_forward_kinematics.py
View File

@@ -22,5 +22,4 @@ if __name__ == "__main__":
n_link_arm.set_joint_angles([random_val(-1, 1) for j in range(len(n_link_arm.link_list))])
ee_pose = n_link_arm.forward_kinematics(plot=True)
print(ee_pose)