This paper presents a new design of pneumatic robot arm system, which uses vision based control method. In our previous research, we designed a vision based light weight robot arm system, but it uses expensive, heavy, and noisy air compressor with valves, and expensive pneumatic regulators. With these limitations, it was difficult to deliver as well as deploy the system at home environment. To solve these problems, we design a low cost pneumatic robot arm system with small and inexpensive air pumps with valves. Also we eliminate pneumatic regulators, which give feedback on the current pressure, from the system, and control the system with real-time vision system that gives feedback on the current positions of robot arm. The proposed system consists of a soft plastic arm, air pumps with valves, two cameras, a control board and a PC. The two cameras are placed in a small baseline stereo setup to provide depth information to carry out the measurements in 3 dimensions. We put color labels on each joint for making it easy and robust to find the positions of each joint. From the experiment, we confirmed that the new low cost system can similarly perform to the previous expensive system.