Andrea Manuello Bertetto

In-pipe inch-worm pneumatic flexible robot

A pneumatic flexible robot prototype for pipes inspection was built. A dynamic model which takes into account the flexibility, damping and friction was developed. Numerous experiments were carried out in order to characterize the robot and in order to provide the input for the numerical model. The model was validated by comparing the experimental and numerical robot gait in time. The robot motion for different pipes network geometry is presented.

Test rig for friction force measurements in pneumatic components and seals

This article describes the design of a new test rig for measuring the friction force in pneumatic components and seals. The test rig was designed in order to measure both the overall friction force in a pneumatic cylinder or a valve as a whole, and the single contribution to friction force caused by the sliding seals. To this end, special fixtures and devices were designed and manufactured in order to measure the friction force in piston seals, rod seals and cartridge valve seals individually. Results of friction measurements carried out on pneumatic cylinders with similar characteristics but produced by different manufacturers are presented and compared. A test procedure and a methodology, in order to separate the contributions of the individual seals from the overall friction of the cylinders, is presented.

Home automation systems and PMV classification for moderate confined environments

The home automation system to control the climatic health in confined environments is the subject of this article. The standard UNI EN ISO 7730:2006 classifies the conditions of moderate confined environments by three categories according to the PMV index. The comfort sensation is mainly affected by four variables: air temperature, mean radiant temperature, air velocity, relative humidity. They are all mechanical and thermal quantities therefore they are measured through the same measurement method. In evaluating the PMV index two more variables are taken into account: metabolism and clothing insulation. They can be evaluated by different accuracy levels. Their indirect measure is subjected to more uncertainty than the above four measuring parameters and the distribution is typically non-Gaussian. The paper analyses the uncertainty in PMV measuring through the Monte Carlo simulation. The proposed study identifies the different weight of independent variables showing as their uncertainty, particularly those referred to metabolism and clothing insulation, affects considerably the final values for classifying the moderate environments.

Human Energy Consumption During Harvesting of Saffron Flowers

In this paper the oxygen uptake using a metabolic measurement system and energy cost of a human operator during the harvesting of saffron flowers are discussed. The measurement of energy cost was performed for a traditional harvesting handmade activity compared to a harvesting phase with a facilitator machine. In the paper the facilitator machine prototype is described and its mechanical performances are presented. The metabolic measurements layout and results are then discussed, the test protocols are declared and the measures outlined and discussed comparing the energy cost with and without facilitator machine. For the experimental evaluation of the energy consumption a significant number of measurement samples for a statistically reliable evaluation has been used. A quantity synoptic parameter has been proposed for the comparison of energy consumption with and without the facilitator machine.

A portable light weight system for saffron harvesting

The system described here is conceived as a shoulder portable device for saffron flowers detaching and collecting. The system is a portable light machine, carried by the human operator on his back during the harvesting phase of the saffron production. The main parts of the system are two: the first one is a gripper designed to detach the flower containing three stigmas, which are the costly final product; the second one is aimed to collect the detached flower through a vacuum collector. In this paper, the operating principles of detaching and collecting devices are described: a model of the gripper is written and compared to the experimental laboratory tests, The model is also used to investigate the system operating principle sensitivity to the variation of some physical characteristics of the gripper. Experimental tests on field are also described to know on field performances of the system.

Human Energy Involved in Manual and Mechanically Facilitate Harvesting of Saffron Flowers

In this work the energy cost of a human operator during the harvesting of saffron flowers is discussed. The amounts of energy cost was achieved for a traditional harvesting hand-made activity compared to a harvesting phase with a facilitator machine. In the paper the facilitator machine prototype is described with its mechanical performances. Oxygen uptake (VO2) and carbon dioxide consumption (VCO2) were taken in five male healthy volunteers using a progressive exercise test on a cycle ergometer to calculate the respiratory ratio (VCO2/VO2) corresponding to the anaerobic threshold (AT) which, just it exceed 1, indicates the fatigue onset. VO2 was also assessed when volunteers simulated hand-made saffron harvesting or assisted by the facilitator device, to establish if the VO2 reached or not the AT value/fatigue onset in the one or in the other harvesting modalities.

Flexible Actuator for Biomorphic Applications: Performances and Energy Consumption Evaluation

The article describes an experimental evaluation of performance of a flexible actuator specially conceived for propulsion of biomorphic robots. Static and dynamic characteristics are presented, particularly referring to the energy consumption.

Semi-Empirical Study of Water Flow Through Vortex Triodes and Performance Optimization

A study was carried out to evaluate behavior and performance of vortex triodes. In particular, the study investigated the geometries and operating conditions which minimize the control flow capable of intercepting the supply flow. The study was conducted experimentally using a specially designed test bench on prototypes operating with water. The geometric parameters which influence vortex valve performance were identified and varied so as to minimize the ratio between control and supply flows. The paper presents a semi-empirical formula to predict vortex valve performance. In particular, the formula takes valve outlet geometry and the shape of outlet diffusers into account