Due to the outstanding characteristics of the large structural flexibility and strong dexterity of soft robots, they have attracted great attention. However, the dynamic modeling and precise control of soft robots face huge challenges. Traditional model-based and model-free control methods find it difficult to obtain a balance between complexity and accuracy. In this paper, a dynamic model of a three-chamber continuous pneumatic manipulator is established based on the modal method. Moreover, a hybrid controller integrating model predictive control (MPC) and iterative learning control (ILC) is proposed, which can simultaneously perform model parameter learning and trajectory tracking control. Experimental results show that the proposed control method can optimize the parameters of the dynamic model in real time with less iterations than the traditional model-free method and have good control performance in trajectory tracking experiments. In the future, the proposed dynamic model and the hybrid controller should be verified on a multi-section manipulator.

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Based on the analysis of echo amplitude envelope and power spectrum of backscattering echo, our group has attempted the characterization of various types of tissue such as liver, lymph node, and skin. For example, the scatterer size estimation of rat liver showed that the estimated size was 30-50 μm. However, it was not investigated how the obtained parameters related to the histology in detail. To resolve this problem, it would be invaluable to understand the spatial distribution of acoustic properties, e.g., speed of sound, attenuation, and acoustic impedance in the scale from micro- to millimeter range. Thus, we measure and accumulate the data using ultrasound with center frequency of 1- 500 MHz. This report introduces the acoustic properties of specimen prepared from two different types of rats: normal liver and liver fibrosis models. A scanning acoustic microscopy using 250-MHz ultrasound with spatial resolution of 7 μm was employed. After the measurement, H&E staining and Masson trichrome staining were conducted to obtain histology. Image registration of SoS image and histology image enabled to separately evaluate SoS of cell nucleus, cytoplasm, and fibrotic tissue. The result demonstrated that there was no significant difference in SoS among cell nucleus, cytoplasm, and fibrotic tissue.

Background: Compound medicines (traditional Chinese medicines [TCM] formulae) are the main means of treating diseases in TCM. Now, for the convenience of clinical use, there are a lot of Chinese patent medicines (proprietary Chinese medicine) on the market. However, the preparation of Chinese patent medicine needs to solve 2 key problems. One is as far as possible to keep crude drug's active ingredients, and the second is the cost control of industrialization; in this article, the extraction process for the proprietary Chinese medicine of the classic TCM formula, Duliang formula, has been studied effectively. Objective: To investigate the optimal ethanol-based extraction process for Duliang formula by central composite design and response surface methodology. Materials and methods: Central composite design was used to carry out a 3-factor 5-level study for a comprehensive evaluation of the extraction process of Duliang formula after normalization processing, with the ethanol concentration, solvent volume, duration, and times of extraction as investigation factors to consider; also, the contents of imperatorin, ferulic acid, and extract yield were determined as Quality Control indicators. Multiple linear regression, binomial fitting, and response surface methodology were used to analyze and determine the optimal ethanol-based extraction process for Duliang formula and predict its extraction parameters. Results: The determined optimal ethanol-based extraction process was thermal reflux extraction twice with 11 times of 90% ethanol for 2.5 h each time. The overall desirability for the “Normalization Value” evaluation was 0.7681, with a deviation of −0.99% (<5%) compared with the predicted value (0.7758). Conclusions: The determined ethanol-based extraction process for Duliang formula was easy and convenient, with stable, accurate, reliable parameters and reasonable predictability, and could serve as a reference for the industrial production of Duliang formula.