Design and Compliant Control of a Piggyback Transfer Robot

2021 ◽  
pp. 1-54
Author(s):  
Yuxin Liu ◽  
Shijie Guo ◽  
Yuting Yin ◽  
Zhiwen Jiang ◽  
Teng Liu

Abstract Patient transfer, such as lifting and moving a bedridden patient from a bed to a wheelchair or a pedestal pan, is one of the most physically challenging tasks in nursing care. Although many transfer devices have been developed, they are rarely used because of the large time consumption in performing transfer tasks and the lack of safety and comfortableness. We developed a piggyback transfer robot that can conduct patient transfer by imitating the motion when a person holds another person on his/her back. The robot consisted of a chest holder that moves like a human back. In this paper, we present an active stiffness control approach for the motion control of the chest holder, combined with a passive cushion, for lifting a care-receiver comfortably. A human-robot dynamic model was built and a subjective evaluation was conducted to optimize the parameters of both the active stiffness control and the passive cushion of the chest holder. The test results of 10 subjects demonstrated that the robot could transfer a subject safely and the combination of active stiffness and passive stiffness were essential to a comfortable transfer. The objective evaluation demonstrated that an active stiffness of k= 4 kPa/mm along with a passive stiffness lower than the stiffness of human chest was helpful for a comfort feeling.

Akustika ◽  
2020 ◽  
pp. 58-66
Author(s):  
Stanislav Žiaran ◽  
Ondrej Chlebo ◽  
Ĺubomír Šooš

The quality of bearing production has an impact not only on their reliability and lifetime, but also on the dynamic load of the working and living environment by excessive vibration and thus also noise. The intensity of the noise emitted by a bearing which is perceived by man characterizes the quality of its production. Reducing the dynamic load of mechanical systems and their components is reflected in the working environment by reducing noise emissions and immissions. The article proposes an objective method of bearing quality assessment based on measuring vibro-acoustic parameters of dynamic load of a new bearing using FFT analysis and the magnitude of the amplitude of bearing vibration acceleration and compares it with a subjective method that also uses the human auditory organ to assess bearing quality. The results of vibro-acoustic measurements were analysed in terms of vibration intensity and the noise of the produced bearings. The proposed objective methodology was compared with the subjective evaluation of the quality of bearings and the results of this methodology matched. The proposed methodology is applicable to all types of bearings, and it is possible to automate this methodology in the production process.


2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Wei Zhou ◽  
Xuexun Guo ◽  
Xiaofei Pei ◽  
Chengcai Zhang ◽  
Jun Yan ◽  
...  

This paper is aimed at the problem that the subjective drivability evaluation by experienced test drivers is limited in time efficiency and is of high cost and poor repeatability. In this article, an intelligent drivability objective evaluation tool (I-DOET) for passenger cars with dual-clutch transmission (DCT) is developed and verified by real vehicle testing. First, the signal denoising method and its key parameters, which are suitable for drivability evaluation, are selected based on analytic hierarchy process (AHP) and technique for order preference by similarity to ideal solution (TOPSIS). Besides, combined with the uncertainty characteristics of subjective judgment, a mathematical model of the objective drivability evaluation FARODE (fuzzy AHP-RS based on objective drivability evaluation) is proposed by using the fuzzy comprehensive assessment (FCA) method. The AHP and rough set (RS) method are used to calculate the subjective and objective weights of the drivability evaluation, respectively, and the proportion of subjective and objective weights is determined by the principle of minimum relative information entropy. The fuzzy matrix is built by membership function of the evaluation indexes. Finally, the static gearshift condition focused on by the subjective evaluation experts is taken as a case study. The predictability score is obtained by combining the drivability quantization lever vector, comprehensive weight, and fuzzy matrix. The experimental results indicate that the proposed method is applicable for objective drivability evaluation in passenger cars with DCT.


Symmetry ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1340 ◽  
Author(s):  
Yaxue Zuo ◽  
Zhenya Wang

Product evaluation is very important for product improvement and development, and subjective product evaluation determines customer’s evaluation of products to some extent, so the purpose of this study is to establish a reasonable subjective product evaluation system. In this study, we comprehensively determine the evaluation indexes based on Kansei engineering (KE), establish an overall product evaluation system by using analytic hierarchy process (AHP), and establish the subjective product evaluation system by classifying the evaluation indexes in the overall product evaluation system into “objective evaluation index” and “subjective evaluation index”, removing the objective evaluation indexes, and retaining the subjective evaluation indexes. Additionally, we select some modern chairs as experimental samples to verify the reliability and validity of this subjective product evaluation system by means of questionnaires. The experimental results show that, in this subjective product evaluation system, the subjective evaluation of the product is positively correlated with the “favorite” level of the product in comprehensive evaluation, and negatively correlated with the “least favorite” level of the product in comprehensive evaluation, indicating that this subjective product evaluation system realizes a symmetry between subjective product evaluation and comprehensive product evaluation. Therefore, it can be concluded that this subjective product evaluation system based on KE and AHP proposed in this study has reliability and validity, and can be used for product evaluation to judge the popularity of products and enhance the competitiveness of products.


2021 ◽  
Vol 13 (10) ◽  
pp. 5549
Author(s):  
Lei Kang ◽  
Zhaoping Yang ◽  
Fang Han

Rapid urbanization promotes the expansion of urban tourism and recreation functions, but it also brings many problems, which affect residents’ happiness. Previous studies have emphasized the direct impact of urban recreation environment on happiness, and few have explored the indirect impact of urban recreation environment on happiness through subjective evaluation. Based on the survey data of nearly 10,000 permanent residents in 40 key tourism cities in China, this paper establishes a theoretical framework of the direct and indirect impact of urban recreation environment on happiness. The objective evaluation of natural recreation environment and sociocultural recreation environment has an important influence on happiness, but the influence of natural recreation environment is greater than that of sociocultural recreation environment. Individual subjective satisfaction with urban recreation environment mediates the relationship between urban objective environment and happiness. Urban parks have a positive effect on happiness, while tourist attractions have a negative effect. The influence of urban location on happiness is nonlinear. The high-income group is more sensitive to the recreation environment, while the low-income group is less sensitive to the recreation environment. These findings provide insights for further improving citizens’ quality of life and designing urban construction in developing countries under the conditions of rapid urbanization.


Author(s):  
Li Jun ◽  
Li Li ◽  
Zhang Yongxiang ◽  
Chu Zhigang ◽  
Fan Xiaopeng

In China, noise pollution from substations in urban areas is becoming more and more serious. An annoyance evaluation of the noise emitted by urban substations is presented. First, the subjective evaluation is conducted on the noise samples from urban substations via the semantic differential method. Subsequently, according to the typical characteristics of urban substation noise, 14 acoustical metrics are used to describe the noise samples for objective evaluation. Then the correlation analysis and regression analysis between the objective and subjective evaluation results are carried out. Finally, a regression model for urban substation noise evaluation is established. Practical application shows that the regression model can correctly predict the subjective annoyance of urban substation noise.


Author(s):  
Linda Tallroth ◽  
Håkan Brorson ◽  
Nathalie Mobargha ◽  
Patrik Velander ◽  
Stina Klasson ◽  
...  

Abstract Background Objectively measured breast softness in reconstructed breasts and its relation to patients’ subjective satisfaction with breast softness has not yet been investigated. The aim of this study was to evaluate breast softness in patients 1 year following delayed breast reconstruction with an expander prosthesis (EP) or deep inferior epigastric perforator (DIEP) flap, using objective and subjective methods. Methods Seventy-three patients were randomised to breast reconstruction with an EP or DIEP flap between 2012 and 2018. Of these, 69 completed objective evaluation at a mean of 25 (standard deviation, SD 9.4) months following breast reconstruction. Objective evaluation included measurements of breast volume, jugulum-nipple distance, clavicular-submammary fold distance, ptosis and Baker scale grading. Breast softness was assessed with applanation tonometry. Subjective evaluation was performed using the BREAST-Q questionnaire. Results Objectively, DIEP flaps were significantly softer than EP breast reconstructions. Non-operated contralateral breasts were significantly softer compared with reconstructed breasts. In the subjective evaluation, the median score on the question (labelled 1.h) “How satisfied or dissatisfied have you been with the softness of your reconstructed breast (s)?” was higher in the DIEP flap group corresponding to greater satisfaction in this group. A fair correlation was found between the applanation tonometry and the patient-reported satisfaction with the reconstructed breast’s softness (rs = 0.37). Conclusions In terms of breast softness, breast reconstructions with DIEP flaps result in more satisfied patients. Concerning applanation tonometry as an objective tool for softness assessment, future studies on interobserver agreement are warranted. Level of evidence: Level I, therapeutic study


2012 ◽  
Vol 472-475 ◽  
pp. 1492-1499
Author(s):  
Run Xia Guo

The Unmanned helicopter (UMH) movement was divided into two parts, namely, attitude and trajectory motion. And then a two-timescale nonlinear model was established. The paper improved and expanded state dependent riccati equation (SDRE) control approach, deriving analytical conditions for achieving global asymptotic stability with lyapunov stability theory. Proof was given. By combining improved SDRE control with nonlinear feed-forward compensation technique, the full envelop flight attitude control laws could be designed. On the basis of attitude control, trajectory controller was developed. Actual flight tests were carried out. Test results show that the control strategy is highly effective.


Author(s):  
Vincent Aloi ◽  
Caroline Black ◽  
Caleb Rucker

Parallel continuum robots can provide compact, compliant manipulation of tools in robotic surgery and larger-scale human robot interaction. In this paper we address stiffness control of parallel continuum robots using a general nonlinear kinetostatic modeling framework based on Cosserat rods. We use a model formulation that estimates the applied end-effector force and pose using actuator force measurements. An integral control approach then modifies the commanded target position based on the desired stiffness behavior and the estimated force and position. We then use low-level position control of the actuators to achieve the modified target position. Experimental results show that after calibration of a single model parameter, the proposed approach achieves accurate stiffness control in various directions and poses.


Author(s):  
Junyi Hou ◽  
Lei Yu ◽  
Yifan Fang ◽  
Shumin Fei

Aiming at the problem that the mixed noise interference caused by the mixed projection noise system is not accurate and the real-time performance is poor, this article proposes an adaptive system switching filtering method based on Bayesian estimation switching rules. The method chooses joint bilateral filtering and improved adaptive median filtering as the filtering subsystems and selects the sub-filtering system suitable for the noise by switching rules to achieve the purpose of effectively removing noise. The simulation experiment was carried out by the self-developed human–computer interactive projection image system platform. Through the subjective evaluation, objective evaluation, and running time comparison analysis, a better filtering effect was achieved, and the balance between the filtering precision and the real-time performance of the interactive system was well obtained. Therefore, the proposed method can be widely applied to various human–computer interactive image filtering systems.


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