The purpose of this research is to present a new method to achieve precise position tracking control for robot finger with variable stiffness mechanism. First, the variable stiffness design of the finger which is actuated by SMA-3 fibers is presented. Then, the relationship between the variation of pulling force ΔF of the bending robot finger and input voltage of SMA-3 is established. In addition, the relationship between the pulling force F and the input voltage of SMA-2 wire is established as well. Therefore, a control method based on these models for the position tracking of robot finger with variable stiffness characteristics is proposed. The experimental results show that the proposed method has better performance than traditional PID control when the stiffness changed by heating current, resulting in a reduction of maximum error by 86%.

A CMOS technology compatible non-volatile SRAM (cNV SRAM) is proposed in this paper to achieve energy efficient on-chip memory. cNV SRAM works as conventional 8T SRAM to keep high speed in work mode; in sleep mode, it backs up the data in its NV component and switches off the power supply, thereby minimizing the leakage energy without data loss. The circuit- and architectural- level implementation schemes of cNV SRAM are developed considering multiple key performance parameters including energy dissipation, access time, write time, noise margin, layout area, restoration time, and injection charges. Simulation results on SPEC 2000 benchmark suite demonstrate that cNV SRAM realizes 86 percent energy savings on average with negligible performance impact and small hardware overhead as compared to conventional SRAM. Finally, the impact of the sleep time and memory size on the effectiveness of cNV SRAM is analyzed in detail and it shows that cNV SRAM is particularly effective to implement large on-chip memories with long idle time.

The modeling and vibration analysis of a flexible manipulator considering a nonlinearity and effect from the gravity imply a singular problem. In order to avoid the singularity, the dynamic equation is decomposed into two subsystems, including flexible dynamic subsystem and rigid dynamic subsystem. A combined feed-forward and feedback control scheme is presented to design the controller of the flexible manipulator. In the combined control, an optimization is applied to obtain the desired trajectory based on the flexible dynamic subsystem. As we know, the optimization is dependent on the accuracy of model but there are inevitably errors of model and external disturbances. The feedback control is expected with high robustness and fast convergence to overcome the problem. In order to improve the performance of control, a hybrid sliding mode control (HySMC) is proposed to track the desired trajectory and further suppress the residual vibration. This paper presents the theoretical derivation and experimental verification of the proposed controller.

A method is proposed to encode multiple regions of interest (ROI) in JPEG2000 image. It rearranges truncation point for every codeblock in each layer. It assigns higher bitrate to ROI and lower bitrate to non-ROI and combines them to codestream. The proposed strategy produces a fully compliant JPEG2000 codestream. It allows transmission of different ROIs with different priorities and supports dynamic delineation and prioritization of them. Experimental results demonstrating the validity of the proposed approach are presented