Adaptive SMC for trajectory tracking in freeform grinding
This work is a first step to the automation of freeform surface grinding. A control strategy for a robotic manipulator following a path which includes switching between different surfaces, constant depths of cut and system-inherent as well as environmental uncertainties is presented. The sliding mode control scheme with adaptive parameter update law is verified through simulation.
Continuous shape-grinding experiment based on constraint-combined force / position hybrid control method
Based on the analysis of the interaction between a manipulator's hand and a working object, a model representing the constrained dynamics of the robot is first discussed. The constraint forces are expressed by an algebraic function of states, input generalized forces, and constraint condition, and then direct position / force controller without force sensor is proposed based on the algebraic relation. To give the grinding system the ability to adapt to any object shape being changed by the grinding, we added estimating function of the constraint condition in real time for the adaptive position / force control, which is indispensable for our method instead of not using force sensor. Evaluations through continuous shape-grinding experiment by fitting the changing constraint surface with spline functions, indicates that reliable position / force control and shape-grinding work can be achieved by this proposed controller.
Industrial inorganic pigments
General Chemical and Physical Properties Behavior of Pigments in Binders White Pigments Titanium Dioxide Zinc Sulfide Colored Pigments Oxides and Hydroxides Cadmium Pigments Bismuth Pigments Ultramarine Pigments Iron Blue Pigments Carbon Black Properties Production Processes Specialty Pigments Magnetic Pigments Anticorrosive Pigments Luster Pigments Transparent Pigments.