scholarly journals RASberry - Robotic and Autonomous Systems for Berry Production

2018 ◽  
Vol 140 (06) ◽  
pp. S14-S18
Author(s):  
Pål Johan From ◽  
Lars Grimstad ◽  
Marc Hanheide ◽  
Simon Pearson ◽  
Grzegorz Cielniak

The soft fruit industry is facing unprecedented challenges due to its reliance of manual labour. We are presenting a newly launched robotics initiative which will help to address the issues faced by the industry and enable automation of the main processes involved in soft fruit production. The RASberry project (Robotics and Autonomous Systems for Berry Production) aims to develop autonomous fleets of robots for horticultural industry. To achieve this goal, the project will bridge several current technological gaps including the development of a mobile platform suitable for the strawberry fields, software components for fleet management, in-field navigation and mapping, long-term operation, and safe human-robot collaboration. In this paper, we provide a general overview of the project, describe the main system components, highlight interesting challenges from a control point of view and then present three specific applications of the robotic fleets in soft fruit production. The applications demonstrate how robotic fleets can benefit the soft fruit industry by significantly decreasing production costs, addressing labour shortages and being the first step towards fully autonomous robotic systems for agriculture.

Author(s):  
K. Ratkovská ◽  
J. Čerňan ◽  
M. Cúttová ◽  
K. Semrád

The operational issues of a small turbojet engine MPM – 20 are discussed. The engine was created by modifying the Soviet turbostarter TS – 20B/21 designed for short-term operation. It is necessary to make structural modifications that allow for the long-term operational premise of the engine. For this purpose, several analyses were focused on the thermally stressed parts. The first, a material analysis carried out on the outer casing of the combustion chamber and on the combustor liner reveals information about the mechanical properties of these structural nodes. It was necessary since there is no documentation of the engine with this information. Another analysis of the infrared emission spectra is important for monitoring operational conditions, especially from the temperature point of view. Subsequent stress analysis of the casing is based on results from previous analyses. It was used to observe the behaviour of the casing as operational conditions changed. This revealed a dangerous increase of thermally induced stress levels as temperature increased up to 150°C. Various structural modifications can be made in the future with these results, such as an application of a protective coating on the casing and combustor liner of the engine.


Rangifer ◽  
1999 ◽  
Vol 19 (4) ◽  
pp. 111 ◽  
Author(s):  
Jouko Kumpula

In arctic and sub-arctic regions semi-domestic reindeer management forms an important livelihood which should be able to provide enough income for herders. Reindeer management has natural limits of growth. Consequently it should be managed to optimise both the use of reindeer pastures and herder income. Reindeer pastures should be grazed at the economic carrying capabity level. This gives the maximum sustained harvest from reindeer stock and also the maximum sustained foraging from pastures. How is this to be accomplished? First, reliable knowledge about reindeer pastures in time and place is necessary: to estimate the quantity and quality of specific reindeer pastures within each management district, as well as the productive capacity and the changes in condition and productivity of those pastures. Secondly, data is needed on the accurate productivity of reindeer stock and the production costs for each management district. Thirdly, study the relationships between pasture resources and productivity of reindeer stock together with the effects of long-term reindeer densities on pasture condition and productivity. Finally, knowledge is needed about the effects of herd structure on reindeer stock productivity as well as the factors which restrict the use of reindeer pastures. Models based on adequate data could provide a useful tool for optimising the use of reindeer pastures and herder income. First the economic carrying capacity of reindeer pastures should be studied. Subsequently the economy of reindeer husbandry could be modelled with respect to reindeer stock density. Also the economy of reindeer husbandry based on different levels of feeding, and the effects of this husbandry practice on pastures, should be modelled. Models should be accurate and flexible enough to use when looking for solutions to practical questions and challenges in reindeer management.


Author(s):  
Sergey Kovalenko

The management of surface watercourses is an urgent scientific task. The article presents the results of statistical processing of long-term monthly data of field observations of hydrological and hydrochemical parameters along the Upper Yerga small river in the Vologda region. Sampling estimates of statistical parameters are obtained, autocorrelation and correlation analyzes are performed. The limiting periods from the point of view of pollution for water receivers receiving wastewater from drained agricultural areas are identified.


The results of experimental studies of masonry on the action of dynamic and static (short-term and long-term) loads are presented. The possibility of plastic deformations in the masonry is analyzed for different types of force effects. The falsity of the proposed approach to the estimation of the coefficient of plasticity of masonry, taking into account the ratio of elastic and total deformations of the masonry is noted. The study of the works of Soviet scientists revealed that the masonry under the action of seismic loads refers to brittle materials in the complete absence of plastic properties in it in the process of instantaneous application of forces. For the cases of uniaxial and plane stress states of the masonry, data on the coefficient of plasticity obtained from the experiment are presented. On the basis of experimental studies the influence of the strength of the so-called base materials (brick, mortar) on the bearing capacity of the masonry, regardless of the nature of the application of forces and the type of its stress state, is noted. The analysis of works of prof. S. V. Polyakov makes it possible to draw a conclusion that at the long application of the load, characteristic for the masonry are not plastic deformations, but creep deformations. It is shown that the proposals of some authors on the need to reduce the level of adhesion of the mortar to the brick for the masonry erected in earthquake-prone regions in order to improve its plastic properties are erroneous both from the structural point of view and from the point of view of ensuring the seismic resistance of structures. It is noted that the proposal to assess the plasticity of the masonry of ceramic brick walls and large-format ceramic stone with a voidness of more than 20% is incorrect, and does not meet the work of the masonry of hollow material. On the basis of the analysis of a large number of research works it is concluded about the fragile work of masonry.


2017 ◽  
Vol 1 (21) ◽  
pp. 65-73
Author(s):  
Monika Gwoździk

The paper presents results of studies on the crystallite sizes of oxide layer formed during a long-term operation on 10CrMo9-10 steel at an elevated temperature (T = 545° C, t = 200,000 h). This value was determined by a method based on analysis of the diffraction line profile, according to a Scherrer formula. The oxide layer was studied on a surface and a cross-section at the outer and inner site on the pipe outlet, at the fire and counter-fire wall of the tube. X-ray studies were carried out on the surface of a tube, then the layer’s surface was polished and the diffraction measurements repeated to reveal differences in the originated oxides layer.


Sign in / Sign up

Export Citation Format

Share Document