Chapter 5, Velocity Kinematics a

5.The kinematics of the 7R WAN robot are given in the Section 4.1.3.
给出Jacobian Body 计算 manipulability elipsoid based on Jv 的方向和长度：

  Jacobian = np.array([
      # [0,-1,0,0,-1,0,0],
      # [0,0,1,0,0,1,0],
      # [1,0,0,1,0,0,1],
      [-0.105,0,0.006,-0.045,0,0.006,0],
      [-0.889,0.006,0,-0.844,0.006,0,0],
      [0,-0.105,0.889,0,0,0,0]
  ])
  JJT = np.matmul(Jacobian,Jacobian.transpose())
  eigenvalue, featurevector = np.linalg.eig(JJT)
  np.set_printoptions(suppress=True)
  print(eigenvalue)
  print("=======选择最大的特征值，开方就是操纵空间主轴长度==========")
  print(featurevector)

答案：[0.08715237,0.99619497,-0.00022828]

6.Referring back to Question 5 and its result,
答案：1.2305