go slightly above the calibration point for safety (#18)

src/KeyboardController.py

@@ -591,6 +591,7 @@ class KeyboardController(Controller):
                 if priors:
                     # calculate IK for next point and move there
                     mat = np.identity(4)
+                    p[3] += 0.01 # go 1cm above bed for safety
                     mat[:3,3] = p
                     mat = world2armT.dot(mat).dot(_vert_or).dot(tip2armT)
                     q = Rotation.from_dcm(mat[:3,:3]).as_quat()