Abstract
The following topics are dealt with: mobile robots; multi-robot systems; path planning; robot vision; service robots; collision avoidance; learning (artificial intelligence); legged locomotion; control engineering computing; production engineering computing.

Abstract
The digital transformation that is on-going worldwide, and triggered by the Industry 4.0 initiative, has brought to the surface new concepts and emergent technologies. One of these new concepts is the Digital Twin, which recently started gaining momentum, and is related to creating a virtual copy of the physical system, providing a connection between the real and virtual systems to collect and analyze and simulate data in the virtual model to improve the performance of the real system. The benefits of using the digital twin approach is attracting significant attention and interest from research and industry communities in the last few years, and its importance will increase in the upcoming years. Having this in mind, this paper surveys and discusses the digital twin concept in the context of the 4th industrial revolution, particularly focusing the concept and functionalities, the associated technologies, the industrial applications and the research challenges. The applicability of the digital concept is illustrated by the virtualisation of an UR3 collaborative robot which used the V-REP simulation environment and the Modbus communication protocol.

Abstract

Abstract
Robotic platforms are being developed for precision agriculture, to execute repetitive and long term tasks. Autonomous monitoring, pruning, spraying and harvesting are some of these agricultural tasks, which requires an advanced path planning system aware of maximum robot capabilities (mobile platform and arms), terrain slopes and plant/fruits position. The state of the art path planning systems have two limitations: are not optimized for large regions and the path planning is not aware of agricultural tasks requirements. This work presents two solutions to overcome these limitations. It considers the VGR2TO (Vineyard Grid Map to Topological) approach to extract from a 2D grid map a topological map, to reduce the total amount of memory needed by the path planning algorithm and to reduce path search space. Besides, introduces an extension to the chosen algorithm, the Astar algorithm, to ensure a safe path and a maximum distance from the vine trees to enable robotic operations on the tree and its fruits.

Abstract
This work describes an experimental setup that was developed in order to automate the one-dimensional consolidation and the direct shear Tests. This experimental setup assures repeatability in the data acquisition, avoiding human errors, mainly when the tests data vary with a high dynamic. The described setup is based on LabVIEW, LVDT sensors and a 16 Bit Data Acquisition Board. For the one-dimensional consolidation test it was used a Load device and a consolidometer, being the experimental setup developed according to the standard ASTM D2435 / D2435M - 11. For the direct shear Test it was used an apparatus, covered in ASTM standard D-3080 / D3080M - 11,”Standard Method for direct shear test on soils under consolidated drained conditions”. © 2019 The authors.

Abstract
Typical vehicle suspension systems are based on passive energy dissipation devices. This type of systems has proven to be a reliable and economic approach, however they are not capable of modify its behavior in accordance with the road conditions. On the other hand, active systems allow a continuous control of the suspension response although requiring sensors, actuators and controllers which represents a more complex and expensive system, usually demanding high power requirements. A middle- term vibration control approach is to use the so-called semi-active systems with the adaptability of active systems and lower energy consumption. This paper aims to evaluate the comfort ridding of a full suspension bicycle equipped with semi-active open loop control suspension system using a magneto-rheological (MR) damper. The assessment is based on the analysis of real data, collected with an instrumented bicycle prototype, obtained in experimental tests carried out on a smooth indoor pavement and on a cobblestone road.