External torque estimation based P+Damping control for bilateral teleoperation systems.

This paper presents a P+Damping control with gravity compensation for bilateral teleoperation systems, where the effects of time delays can be effectively addressed, and the motion synchronization and the transparency can be guaranteed. To further eliminate the direct measurement of human and environmental torques to save sensor installation space and reduce the hardware cost, a constructive unknown torque estimator is also proposed by tailoring the idea of unknown system dynamics estimator (USDE). This torque estimator with low-pass filter operations eliminates the requirement of joint acceleration and has only one tuning parameter, while it enables accurate estimation of external torques of both the local and remote manipulators.

Investigation of the Pozzolanic Activity Improvement of Yellow Phosphorus Slag with Thermal Activation.

Yellow phosphorus slag (YPS) is a byproduct from the production of yellow phosphorus. It has potential pozzolanic activity and can be used as a supplementary cementitious material. However, the early strength of cement mortar decreases significantly with increasing YPS dosage, which restricts the utilization of YPS in cement and concrete.