Abstract---After the new definition of kilogram in the International System of Units (SI), in the field of micro mass measurement, methods such as Kibble balance, electrostatic force and photon pressure are becoming new research fields in direct mass measurement with SI traceability .The calibration of small masses, especially in the mass calibration range of less than 50 μg, is becoming possible with these methods in the mass metrology field, such as the sensitivity calibration of electromagnetic balances with resolution of 10 ng and the measurement of mass changes of electromagnetic balances caused by magnetic measurements. For mass metrology, the physical weights below 50 μg are very difficult to manufacture and implement because of the small quantity value, and difficult to operate, so it is impossible to realise the calibration of the physical microweights to the micro mass of the microbalance. Usually for 100 μg physical weights, the uncertainty is usually 0.3 μg, the relative standard uncertainty is about 0.3 %. On the nanogram scale, the relative uncertainty of the physical weights may exceed 100 %. Thus the weights of steel or other material is not a suitable option for mass standards below 50 μg. The laser photon-momentum-based method is more and more used in the optical power measurements. As a revert use, the laser optical power can be used as a traceable source to small mass in micro range using the same photonmomentum-based method to new SI with better measuring accuracy. The sensitivity calibration for mass comparator based on laser optical force was carried out using an optical power range between 20 W and 120 W at a wavelength of 1080 nm. The air density meter is used to sense the stability of the laser power and optical force. Uncertainty of measurement is evaluated. With a coverage factor k = 2, relative expanded uncertainty of reference sensitivity mass standard using photon force of laser is better than 2 %. The uncertainty of the sensitivity calibration is also investigated. Keywords: optical force; microgram calibration; mass metrology

The laser photon-momentum-based method is more and more used in the optical power measurements. As a revert use, the laser optical power can be used as a traceable source to small mass in micro range using the same photon-momentum-based method to new SI with better measuring accuracy. The sensitivity calibration for mass comparator based on laser optical force was carried out using an optical power range between 20 W and 120 W at a wavelength of 1080 nm. The air density meter is used to sense the stability of the laser power and optical force. Uncertainty of measurement is evaluated. With a coverage factor k = 2, relative expanded uncertainty of reference sensitivity mass standard using photon force of laser is better than 2 %. The uncertainty of the sensitivity calibration is also investigated.

为了实现对拖拉机空调电机转速的精确控制,设计了一种基于单片机和模糊PID的转速单闭环无刷直流电机控制系统,可以对电机转速进行控制调节,从而驱动制冷压缩机工作,降低拖拉机车内温度.实验结果表明:基于单片机和模糊PID的拖拉机空调电机控制系统稳态误差较小,控制精度较高,与理论基础相符合,证明了该方法的可行性和正确性.

为了实现采摘机器人通过手势动作进行远程控制的目标,采用MYO手环采集人体手势动作信号,将信号进行滤波、放大和A/D转换等预处理后,通过无线通信模块发送给PC机;PC机提取右移、左移和采摘等动作的特征值,送入RNN网络中进行训练和识别,并将识别结果以指令的方式发送给采摘机器人,控制采摘机械手进行相应操作.实验结果表明:采摘机器人SEMG手势识别算法识别率较高,结果非常理想,验证了采摘机器人通过手势进行远程控制的可行性.

To improve measurement efficiency, calibration laboratories are gradually employing automatic measurement systems instead of manual measurements. At present, the data directly generated by the automatic measurement system focuses on the presentation of the measurement results but lacks the key information elements required by ISO-17025 for the original records and certificate reports. In the meantime, when carrying out mass measurements in small nominal values, it is easy to generate incomplete data due to measurement interruptions caused by falling weights. After the measurement, it is often necessary for inspectors to process data manually. Therefore, in the actual inspection work, the data analysis and processing of the automatic measurement system still require a lot of manpower. In this paper, combined with the features of mass measurements in small nominal value, a data analysis and processing method based on the automatic measurement system was proposed. Functions such as automatic segmentation and reorganization of data, identification of unqualified results, and processing of incomplete data were added. reduces the interference of human factors. The method realized automatic analysis of data, automatic generation of original records and certificate reports, reduced human factor interference, and further enhanced the efficiency of quality inspection and automatic data processing and analysis.

以农用蓄电池电机车为研究对象,首先介绍了电机内部结构、工作原理及其数学模型;然后,对比了常规和农用蓄电池两种电机车的电机调速控制方法;最后,基于模糊PID控制技术实现了农用蓄电池电机车调速系统.实验结果表明:农用蓄电池电机车电机变速系统驱动控制能力强,具备启动速度快和抗干扰能力强等优点.

高准确度质量测量时需要修正由于被测砝码与标准砝码质心高度差引入的质量差值,因此需要测量质量标准的质心高度.质心高度可通过将质量标准按不同朝向放置在称量桥的不同位置,根据质量测量仪器的示值变化计算得到.研究了 2种质心高度测量方法的不确定度评定,分析了各不确定度来源,给出了不确定度评估方法,并结合实例进行了讨论.

为了提高采摘机器人机械手果实的定位精度,降低果实采摘过程的破损率,将模糊算法和PID控制引入到了机械手控制系统的设计上,并采用PC上位机编程和嵌入式系统实现控制算法的运行.为了验证算法的可行性和可靠性,以果实采摘真实环境为测试环境,对机械手的定位精度和果实采摘的破损率进行了测试,结果表明:采用模糊PID算法可以明显提高机械手的果实定位精度,降低果实采摘的破损率,对采摘机器人控制系统的优化设计具有重要的参考价值.

Continuous totalizing automatic weighing instruments is widely used in many industries, and need to be tested under different conditions especially for different temperature, humidity and electrical disturbance. Usually this kind of weighing instruments are very large and can not be put into such test environments, thus a test sample without belt conveyor is needed. Due to the working principle of continuous totalizing automatic weighing instruments, the test sample may include not only essential part of weighing instruments such as load cell, indicator, and load receptor, but also a device to simulate the displacement of the belt. In the paper, a device that can simulate the velocity of the belt is researched, it can generate square pulse signals to the test sample, thus the sample can operate as normal belt weigher. The configuration of the device is discussed and example is given to show its effectiveness.

为简化采摘机器人底层控制系统软硬件设计,提高系统的实时性和可靠性,在处理器的设计上引入了嵌入式微处理器,取代了常规的单片机和PLC方案.提出了基于ARM控制器和源代码开放的Linux操作系统组成的采摘机器人控制系统,对其实时避障功能进行了设计,并模拟采摘机器人作业环境对该方案的可行性进行了测试.结果表明:采摘机器人行使过程中可以躲避障碍物,向目标作业区域移动,成功地实现了实时避障功能,为采摘机器人自主导航系统的开发提供了重要的借鉴.

本项研究测量了AuNP的k壳层X射线荧光强度.测量到了AuNP溶液浓度在0.1～4.0mg/mL的金元素k壳层荧光光谱特征峰,并得到了特征峰强度与AuNP浓度的线性校准曲线,将金k壳层X射线荧光特征峰在AuNP溶液中可被探测的能力和灵敏度提高了一个数量级,并且扎实地达到了0.1mg/mL.

质量单位是国际单位制中7个基本单位之一,在量值传递体系中占有举足轻重的地位.为了应对质量单位重新定义的国际变革,确保千克重新定义后量值传递准确可靠,基于我国能量天平和真空质量测量装置的结构特点,提出了真空容器+双真空传递腔体的量值传递关键技术,实现了实物砝码从真空容器到真空质量测量装置(M-one)的准确可靠传送和真空质量测量.

The dissemination method after redefinition of mass unit will be changed from Planck constant to primary mass standard and from primary mass standard to secondary mass standard. The measurement of weights under vacuum will replace the measurement of weights in air. M-one manufactured by Mettler-Toledo company is a product for measuring the mass of an object under vacuum. In order to transfer weights from vacuum vessel to M-one, a vacuum transfer equipment (VTE) is developed by National Institute of Metrology, China (NIM). A multistage manipulator system is designed to transfer weight under vacuum between VTE and M-one. The experimental results show that the performance of VTE is efficient for transferring the weights under vacuum.

Stable and uniform sound distribution is a key factor in high precise volume determination of solid material especially for mass standards. A numerical study is carried out to study the distribution and uniformity of sound pressure. The FEM simulation results show that the sound pressure distribution gradient of the small chamber is better than large chamber. With the FEM model in this paper, the maximum sound pressure level change is only 0.003 DB (RMS). And also for small chamber, the sound pressure signals are higher and more easily to be acquired for real measuring system.

The acoustic volume measuring method is a promising non-contact method for volume determination of mass weights. To improve the measuring accuracy of volume determination with the non-contact acoustic method, an acoustic measuring system with two measuring chambers is newly designed to compensate for the non-linearity measuring errors. When reducing the remaining air in the measuring chamber, the measuring accuracy can be greatly reduced. The volumes of mass standards ranging from 100 g to 5 kg are tested to evaluate the non-linearity errors of the volume measurement. The relative uncertainties of the acoustic volume determination are below 7.0 ×10-4 (k=2).

This paper analyses the influence of air pressure regarding the precise mass measuring process. The stability of air pressure to the mass determination process is discussed experimentally using the new M-one mass comparator. Due to the change of air pressure, air flow and vibration with regard to the weighing hanger can be arisen. The vibration of weighing hanger is from both the base and the air flow. Under air pressure control, the standard deviation of weighing process can be reduced to 0.39 mu g.

动态汽车衡的型式评价依据为目前现行有效的JJG907-2006《动态公路车辆自动衡器检定规程》和GB/T21296-2007《动态公路车辆自动衡器》.动态汽车衡在进行型式评价时需明确其计量参数,其中分度值d是非常重要的一个参数,但常常不被企业人员重视.

重力式自动装料衡器与非连续累计自动衡器是两种广泛使用的自动衡器,具有不同的原理和计量特性.然而这两类衡器在结构上具有一些相似之处,易于造成混淆.本文从计量特性角度出发,研讨了这两类衡器的差异,并以装车站为实例进行了分析,从而说明了重力式装料衡器与非连续累计自动衡器是不同的两类衡器,并明确了如何区分这两类自动衡器.

连续累计自动衡器是自动衡器的重要分支之一,是受法制计量管理并列入我国《依法管理的计量器具目录（型式批准部分）》的计量器具。本文就该计量器具进行型式评价过程中涉及的关键技术参数进行讨论,并就型式评价试验要求,特别是现场试验的要求和测试难点进行了讨论和分析。

CCM.M-K4 is a key international comparison organized by the Bureau International des Poids et Mesures (BIPM) to verify the measurement ability of 1kg stainless weights. This paper reports the process analysis of mass determination of CCM.M-K4 during the measurement in NIM, China. The gravity correction and air bouncy correction are discussed, and the measuring uncertainties of measurement process are evaluated. Mass difference between the test standards is 0.0015 mg, and average mass of both test standards is 0.013 mg. The standard uncertainty of test weights is 0.013 mg.