**3.2. Basic tendon of index finger for identification of EMG signal**

To examine the bio-mimetic behavior of IPMC based artificial muscle finger, it is important to study the physiological structure of human finger. An internal structure of human index finger is shown in Fig. 3. The index finger is actuated by three intrinsic muscles and four extrinsic muscles. The intrinsic muscles consist of two interosseous (IO 1 and IO 2) muscles & one lumbrical (LU) muscle and four extrinsic muscles connected through long tendons i.e. extensor digitorum communis (EDC), extensor indicis proprius (EIP), flexor digitorum superficialis (FDS) and flexor digitorum profundus (FDP) (Bundhoo & Park, 2005). For heavy lifting & holding purpose, EDC and EIP are responsible in tendon network. Consequently, EMG electrodes are placed at these two positions on the human finger so that we can achieve direct actuation of IPMC based artificial muscle finger through said muscles.

**Figure 3.** Basic tendons of the index finger (Bundhoo & Park, 2005)
