Mario Di Castro, Alessandro Masi, Giacomo Lunghi, Roberto Losito
An incremental slam algorithm for indoor autonomous navigation

Robots indoor autonomous navigation is a crucial requirement for many challenging applications like the inspection of unstructured and harsh environments. Simultaneous Localization and Mapping (SLAM) is a key component to navigate autonomously. A novel embedded incremental algorithm that could be used on ground or aerial robots to localize and create 3D maps of an unknown GPS-denied environment, is presented. The algorithm is processing-wise light, is executed on board in real time and is suitable to be integrated in a full framework for autonomous navigation. It has been validated using a minimal set of sensors composed of a laser scanner and an inertial unit. Preliminary test results of the algorithm are presented using the CERN test facilities as case study.

Kun-Chih Tsai, Win-Ti Lin, Jiunn-Haur Shaw, Cheng-Tsair Yang, Chun-Min Su
LEGAL METROLOGY CONTROL OF A LIQUEFIED PETROLEUM GAS TRANSFER STANDARD AND FIELD PRACTICE

The paper presents construction, metrological testing and field practice of a Liquefied Petroleum Gas (LPG) transfer standard (TS). This meter package was tested first with water as working medium and re-tested with propane and butane at the National Measurement Institute of Australia (NMIA). The rational is that NMIs maintaining LPG legal measurement infrastructure could simplify the traceability method by utilizing water as test medium while keeping the same accuracy. In addition, the meter package is intended to replace the conventional gravimetric approach, which requires tedious in-situ testing process for a LPG fuel dispenser. The project is supported by Asia Pacific Metrology Program (APMP) Technical Committee Initiative fund.

Carme Valero, Eduard Egusquiza
Condition monitoring of Pump-turbines

At present, new renewables like wind, solar and marine energy are having a strong development. The generation of energy by renewables has the disadvantage that it depends on atmospheric conditions. It means that they can generate energy at any moment independently if this energy is required or not by the consumers.
For the stability of the electrical grid, supply and demand of energy has to be matched. The surplus of energy produced when consumption is low has to be stored and delivered again when consumption is high. Therefore, the future of renewables is tied directly to the future of energy storage.
At present, the only system to store huge amounts of energy is pumped storage (Pump-turbine machines). In these plants the surplus of energy in the grid is used for pumping water to a higher reservoir (pump operation). At peak hours or in case of emergency this water goes down generating energy (turbine operation). To guarantee this operation these machines have to be available at any time.
Pump-turbines (PT) are high performance machines that have to change operation from pump to turbine mode (reversing runner rotation and flow direction) in a short time. Due to their design characteristics (large power concentration) and operating conditions, they generate large pressure pulsations and forces when in operation. The PT structure has to resist all these forces and keep stresses below fatigue limit, for a lifespan of several decades.
With the increasing production of new renewables and the market regulations, new scenarios are appearing with:
- a large increase in the number of start and stop cycles
- a longer time of off-design operation at very low loads.
Due to these facts the machines suffer from large hydraulic forces generating strong vibrations and stresses especially in the runner. Improved (and affordable) monitoring techniques are necessary.

Loredana Cristaldi, Marco Faifer, Massimo Lazzaroni, Mohamed Mahmoud Abdel Fattah Khalil, Marcantonio Catelani, Lorenzo Ciani
Failure Modes Analysis and Diagnostic Architecture for Photovoltaic Plants

Failure modes analysis and diagnostic architectures are very interesting aspects for plants based on PV panel. In fact, these plants are called to operate for many years. The monitoring of plant parameters and performances is a very important task that can be obtained by means a well-designed monitoring system. This approach allows to improve complex system maintenance policies and, at the same time, to achieve a reduction of unexpected failure occurrences in the most critical components.

M. Catelani, L. Ciani, S. Rossin, M. Venzi
Failure rates sensitivity analysis using Monte Carlo simulation

This paper is focused on sensitivity analysis achieved on system reliability: sensitivity assessment allows putting in discussion nominal values taken from a generic database and focus on uncertainty quantification and propagation of uncertainty from input to output. There are many sources of uncertainty that can affect input data and this uncertainty imposes a limit on our confidence in the response of the model. In this paper sensitivity analysis is achieved on GE Oil&Gas mineral lube oil console, a system forced to endure extreme process and environmental conditions. In order to have a wide sample survey Monte Carlo simulation is used supposing two different probability distributions (uniform and normal) for failure rates coming from OREDA Offshore Reliability Data Handbook.