【正文】 with equilibrium of forces, decrease the mand position X0 in a constant rate, then the balance has been broken. For the feedback of error of position increasing, the actual pressure will bee smaller and try to go to another equilibrium state. The actual lifting force is less than the weight of the workpiece, gripper, and its support now. So the workpiece moves down until touching the lower die. At this moment, the actual pressure drops rapidly. According to the change rate of pressure, the workpiece placement state can be identified automatically. Keep the mand position X0 with the height value of workpiece position placed on the lower die. The pressure and position of lifting cylinders goes to a new balance. Figure5: Illustration of the placement of workpiece. . Compliance in Vertical Direction and Move Up Automatically As shown in Figure 6, when the workpiece is pressed by the upper die, the load on cylinder will increase for the deformation of workpiece。附錄（二） 原文： Intelligent Control of a Novel Hydraulic Forging Manipulator Abstract The increased demand for largesize forgings has led to developments and innovations of heavyduty forging manipulators. Besides the huge carrying capacity, some robot features such as force perception, delicacy and flexibility, forging manipulators should also possess. The aim of the work is to develop a heavyduty forging manipulator with robot features by means of bination of methods in mechanical, hydraulic, and control field. In this paper, through kinematic analysis of a novel forging manipulator, control strategy of the manipulator is proposed considering the function and motion of forging manipulators. Hybrid pressure/position control of hydraulic actuators in forging manipulator is realized. The feasibility of the control method has been verified by the experiments on a real prototype of the novel hydraulic forging manipulator in our institute. The intelligent control of the forging manipulator is performed with programmable logic controller which is suitable for industrial applications. 1. Introduction The use of manipulators in open die or free forging can be traced back about 60 years when development started in both Europe and the USA. Manipulators for heavy workpieces, that is, those in the region of 200 tons weight, have been developed steadily since that time, and currently there are a number of examples of putercontrolled fully automatic forging manipulators being used . As a result of the practical use of the control system, the operators were released from mental stress, the training period for operators was reduced, the uniformity of forging quality was improved, and a higher production rate was attained . Control of the manipulators involves rotational control in the continuous rotation and incremental angle rotation modes. The manipulator position requires integrated control with the press to achieve inches per press stroke while pensating for workpiece length increase due to crosssection area reduction of workpiece . Vitscheff demonstrates the need for pliance control when robots are used to manipulate the workpiece during forging. Specifically, the external forces exerted on the manipulator through its manipulation of the workpiece during forging steps must be minimized to avoid damage to the robot mechanism. An ASEA robot was used as an opendie forging manipulator. The ASEA robot has an inbuilt Intel microprocessor which controls its arm and gripper movements in five axes. The robot was used in conjunction with a fielding hydraulic press . The application of neural works for pliance control of the forging robot was investigated. Effectiveness of the neural workbased pliance control module is evaluated through a full dynamic system simulation . An integrated forging plant, 25?MN open die press with 200?kN and 400?kNm manipulators, was built in 1999. The workpiece is put into position by two railbound manipulators with rotation and travel movements actuated by closed hydraulic circuits to reduce energy consumption and shocks and to improve positioning . The railbound forging manipulator with a carrying capacity of 1600?kN and 4000?kNm load moment started its operation in 2020 at JSW. The manipulator supports a straight line peel movement as well as an accurate and stable positioning which is possible because of the special lever arrangement . The increased demand for largesize forgings has led to developments and innovations all around the improvement of quality and productivity. Many efforts have been undertaken to research and develop heavyduty forging manipulators. The researches in recent years focus on the mechanisms of forging manipulator, such as kinematic modeling and analysis 。 dynamic load analysis