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During the working of portable flexible CMM, the mechanical arm΄s gravity and operating load generate dynamic strain, the thermal distortion also results in its length change. The caused errors would severely deteriorate the measuring accuracy. An error compensating system of the mechanical arm is designed in this paper, based on the monitor of dynamic strain and environmental temperature. The mathematical model of portable flexible coordinate measuring machine (CMM) was established.For the dynamic strain, four resistance strain gauges are sticked symmetrically on the root of each mechanical arm to monitor the dynamic strain. Then length error caused by the measuring arm΄s gravity or external operation load can be calculated through the analysis of stress. Strain compensation can be realized, when they are fed back to the measurement procedures. For thermal distortion, the temperature values acquired by the single-linear digital thermometer are substituted in the correction formula to calculate the relevant compensation dosage. Finally, these compensation dosages are feedbacked to the measuring program to have these errors compensated continually. The integrated error compensation system can improve the measurement accuracy of portable flexible CMM effectively. [ABSTRACT FROM AUTHOR]

Non-contact measurement is widely used for free-form surface inspection due to its effectiveness and convenience. However, the non-contact measurement accuracy is one order less than tactile probe. In this paper, a method of error analysis and compensation for a laser scanner on Articulated Arm Coordinate Measuring Machines (AACMMs) is presented. Based on the constrained optimization algorithm, the coordinate transformation is obtained between low accuracy data and high accuracy data. The deviations between the reference points to the datum are calculated. The average deviation as an error compensation value is used to correct other point clouds for reducing the measurement system errors. Experimental results show that this method can improve the accuracy of laser scanning data on AACMMs. [ABSTRACT FROM AUTHOR]

Molecular communication is a novel paradigm that uses molecules as an information carrier to enable nanomachines to communicate with each other. Controlled molecule delivery between two nanomachines is one of the most important challenges which must be addressed to enable the molecular communication. Therefore, it is essential to develop an information theoretical approach to find out communication capacity of the molecular channel. In this paper, we develop an information theoretical approach for capacity of a molecular channel between two nanomachines. Using the principles of mass action kinetics, we first introduce a molecule delivery model for the molecular communication between two nanomachines called as Transmitter Nanomachine (TN) and Receiver Nanomachine (RN). Then, we derive a closed form expression for capacity of the channel between TN and RN. Furthermore, we propose an adaptive Molecular Error Compensation (MEC) scheme for the molecular communication between TN and RN. MEC allows TN to select an appropriate molecular bit transmission probability to maximize molecular communication capacity with respect to environmental factors such as temperature and distance between nanomachines. Numerical analysis show that selecting appropriate molecular communication parameters such as concentration of emitted molecules, duration of molecule emission, and molecular bit transmission probability it can be possible to achieve high molecular communication capacity for the molecular communication channel between two nanomachines. Moreover, the numerical analysis reveals that MEC provides more than % 100 capacity improvement in the molecular communication selecting the most appropriate molecular transmission probability. [ABSTRACT FROM AUTHOR]