Beispiel #1
0
    def jacobian(self, x, fp, fr, goal, weights, des_r, des_t):
        """ Find parent rotations """
        prs = fr[:, self.animation.parents]
        prs[:, 0] = Quaternions.id((1))
        """ Get partial rotations """
        qys = Quaternions.from_angle_axis(x[:, 1:prs.shape[1] * 3:3],
                                          np.array([[[0, 1, 0]]]))
        qzs = Quaternions.from_angle_axis(x[:, 2:prs.shape[1] * 3:3],
                                          np.array([[[0, 0, 1]]]))
        """ Find axis of rotations """
        es = np.empty((len(x), fr.shape[1] * 3, 3))
        es[:, 0::3] = ((prs * qzs) * qys) * np.array([[[1, 0, 0]]])
        es[:, 1::3] = ((prs * qzs) * np.array([[[0, 1, 0]]]))
        es[:, 2::3] = ((prs * np.array([[[0, 0, 1]]])))
        """ Construct Jacobian """
        j = fp.repeat(3, axis=1)
        j = des_r[np.newaxis, :, :, :,
                  np.newaxis] * (goal[:, np.newaxis, :, np.newaxis] -
                                 j[:, :, np.newaxis, np.newaxis])
        j = np.sum(j * weights[np.newaxis, np.newaxis, :, :, np.newaxis], 3)
        j = self.cross(es[:, :, np.newaxis, :], j)
        j = np.swapaxes(
            j.reshape((len(x), fr.shape[1] * 3, goal.shape[1] * 3)), 1, 2)

        if self.translate:

            es = np.empty((len(x), fr.shape[1] * 3, 3))
            es[:, 0::3] = prs * np.array([[[1, 0, 0]]])
            es[:, 1::3] = prs * np.array([[[0, 1, 0]]])
            es[:, 2::3] = prs * np.array([[[0, 0, 1]]])

            jt = des_t[np.newaxis, :, :, :,
                       np.newaxis] * es[:, :, np.newaxis,
                                        np.newaxis, :].repeat(goal.shape[1],
                                                              axis=2)
            jt = np.sum(jt * weights[np.newaxis, np.newaxis, :, :, np.newaxis],
                        3)
            jt = np.swapaxes(
                jt.reshape((len(x), fr.shape[1] * 3, goal.shape[1] * 3)), 1, 2)

            j = np.concatenate([j, jt], axis=-1)

        return j
Beispiel #2
0
    def jacobian(self, x, fp, fr, ts, dsc, tdsc):
        """ Find parent rotations """
        prs = fr[:, self.animation.parents]
        prs[:, 0] = Quaternions.id((1))
        """ Find global positions of target joints """
        tps = fp[:, np.array(list(ts.keys()))]
        """ Get partial rotations """
        qys = Quaternions.from_angle_axis(x[:, 1:prs.shape[1] * 3:3],
                                          np.array([[[0, 1, 0]]]))
        qzs = Quaternions.from_angle_axis(x[:, 2:prs.shape[1] * 3:3],
                                          np.array([[[0, 0, 1]]]))
        """ Find axis of rotations """
        es = np.empty((len(x), fr.shape[1] * 3, 3))
        es[:, 0::3] = ((prs * qzs) * qys) * np.array([[[1, 0, 0]]])
        es[:, 1::3] = ((prs * qzs) * np.array([[[0, 1, 0]]]))
        es[:, 2::3] = ((prs * np.array([[[0, 0, 1]]])))
        """ Construct Jacobian """
        j = fp.repeat(3, axis=1)
        j = dsc[np.newaxis, :, :,
                np.newaxis] * (tps[:, np.newaxis, :] - j[:, :, np.newaxis])
        j = self.cross(es[:, :, np.newaxis, :], j)
        j = np.swapaxes(j.reshape((len(x), fr.shape[1] * 3, len(ts) * 3)), 1,
                        2)

        if self.translate:

            es = np.empty((len(x), fr.shape[1] * 3, 3))
            es[:, 0::3] = prs * np.array([[[1, 0, 0]]])
            es[:, 1::3] = prs * np.array([[[0, 1, 0]]])
            es[:, 2::3] = prs * np.array([[[0, 0, 1]]])

            jt = tdsc[np.newaxis, :, :,
                      np.newaxis] * es[:, :, np.newaxis, :].repeat(
                          tps.shape[1], axis=2)
            jt = np.swapaxes(
                jt.reshape((len(x), fr.shape[1] * 3, len(ts) * 3)), 1, 2)

            j = np.concatenate([j, jt], axis=-1)

        return j
Beispiel #3
0
    def __call__(self):

        children = AnimationStructure.children_list(self.animation.parents)

        for i in range(self.iterations):

            for j in AnimationStructure.joints(self.animation.parents):

                c = np.array(children[j])
                if len(c) == 0: continue

                anim_transforms = Animation.transforms_global(self.animation)
                anim_positions = anim_transforms[:, :, :3, 3]
                anim_rotations = Quaternions.from_transforms(anim_transforms)

                jdirs = anim_positions[:, c] - anim_positions[:, np.newaxis, j]
                ddirs = self.positions[:, c] - anim_positions[:, np.newaxis, j]

                jsums = np.sqrt(np.sum(jdirs**2.0, axis=-1)) + 1e-10
                dsums = np.sqrt(np.sum(ddirs**2.0, axis=-1)) + 1e-10

                jdirs = jdirs / jsums[:, :, np.newaxis]
                ddirs = ddirs / dsums[:, :, np.newaxis]

                angles = np.arccos(np.sum(jdirs * ddirs, axis=2).clip(-1, 1))
                axises = np.cross(jdirs, ddirs)
                axises = -anim_rotations[:, j, np.newaxis] * axises

                rotations = Quaternions.from_angle_axis(angles, axises)

                if rotations.shape[1] == 1:
                    averages = rotations[:, 0]
                else:
                    averages = Quaternions.exp(rotations.log().mean(axis=-2))

                self.animation.rotations[:,
                                         j] = self.animation.rotations[:,
                                                                       j] * averages

            if not self.silent:
                anim_positions = Animation.positions_global(self.animation)
                error = np.mean(np.sum((anim_positions - self.positions)**2.0,
                                       axis=-1)**0.5,
                                axis=-1)
                print('[BasicInverseKinematics] Iteration %i Error: %f' %
                      (i + 1, error))

        return self.animation
Beispiel #4
0
 def quaternions(self, plane='xz'):
     fa = self._ellipsis()
     axises = np.ones(self.ps.shape + (3, ))
     axises[fa + ("xyz".index(plane[0]), )] = 0.0
     axises[fa + ("xyz".index(plane[1]), )] = 0.0
     return Quaternions.from_angle_axis(self.ps, axises)