Dr. Kochin was Dr. Wheelo’s assistant, who was actually a robot (although he may have originally been human). Even though he appeared old and harmless, Dr. Kochin was actually well-equipped for fighting: his hand could transform into a machine gun, while his cane, which bore a stylized headpiece of Shenron, could hurl energy blasts.
Kochin is the one who created the three biotechnical warriors Kishime, Misokatsun and Ebifurya. He gathered the Dragon Balls and used his wish to free Dr. Wheelo from his icy prison in the Tsurumaitsuburi Mountains after fifty years.
Kochin was killed when Dr. Wheelo accidentally knocked him over a ledge in the laboratory; his body got too close to the wall (actually a huge conductor for powering Wheelo’s robot body). Revealed as a full robot in the end, his body was electrocuted and exploded.