Risto Tiusanen

Dr. Risto Tiusanen

orcid

Research Focus & Metrics

Academic Career Length

39Years (1988-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
1 January 2020 in Open Engineering
Verified
Journal Article
Open access
PDF file
RTRisto Tiusanen
Risto Tiusanen
TMTimo Malm
Timo Malm
ARAri Ronkainen
Ari Ronkainen
The development of automated work machine systems towards autonomous operation is proceeding rapidly in different industrial sectors. The aim of the study was to explore the current situation and possible differences in standardization supporting the development in different industrial sectors. The existing ISO and IEC standards and work items related to autonomous machinery were reviewed as well as activities in international industry groups regarding automation and autonomy of machinery. In general, the current standards are made mostly for machine manufacturers, but the views or responsibilities at worksite level are not considered. Three different approaches for safety concepts for different operating conditions were identified. One of them relies on onboard safety systems including sensor and perception systems for indoor applications. One guides to separate and isolate the autonomously operating machinery and to use access control to the autonomous operating zone. The third one is relying mainly on the machine operator’s ability to understand the situation and to react correctly according to the available information. From technology point of view there seems to be a gap between the safety requirements set in standards and the state of the art in currently available technology.

1 January 2022 in Open Engineering
Verified
Journal Article
Open access
PDF file
TMTimo Malm
Timo Malm
RTRisto Tiusanen
Risto Tiusanen
Eetu HeikkiläEetu Heikkilä
Eetu Heikkilä
JSJanne Sarsama
Janne Sarsama
Autonomous mobile machines are applied increasingly often in outdoor applications, but only in places, where logistic problems and safety issues are resolvable. Solving safety issues require good hazard identification and risk estimation. The aim of this study is to show which new risks emerge in autonomous mobile machines compared to manual machines. There are new risks, which are valid only in autonomous mobile machines (e.g., related to sensors for situational awareness), and risks, which exist in both machine types, but human presence can make the difference in resolving the situation. Humans can take sophisticated protective measures during an unexpected hazardous situation. Another aim of this work is to give information to designers and assessors to consider risks of their own design. Autonomous mobile machines are complex, and their performance is not always easily predictable. A checklist of risks would help an assessor, but currently, it may be difficult to find a checklist for a specific autonomous mobile machine. The main result of this study is a checklist of new risk sources or hazards of autonomous mobile machines.

27 September 2022 in Drones
Verified
Journal Article
Open access
PDF file
EÖEmrehan Öz
Emrehan Öz
Eetu HeikkiläEetu Heikkilä
Eetu Heikkilä
RTRisto Tiusanen
Risto Tiusanen
To govern and ensure the safety of increasing drone operations, the European Aviation Safety Agency (EASA) has defined three risk-based categories of unmanned aircraft system (UAS) operations. A large part of commercial UAS operations fall into the Specific category, which includes operations with medium risk that require an authority approval. One possible way to gain approval for these operations is the light UAS operator certificate (LUC) awarded by a national aviation authority. It offers organisations the privilege to assess and approve operations without applying for authorisation from an authority. However, only general information regarding the LUC is available in the European regulatory publications. Thus, there is currently a lack of detailed guidelines and practical information about the process and requirements for acquiring LUC status. This paper describes the development of a LUC application process model following a design science research approach. The model supports organisations to assess their LUC capabilities, develop their organisation, create the documentation to fulfil relevant requirements, and to apply for the certificate. Finally, the results of a case study where the process model was applied are presented.

Verified
Journal Article
Open access
PDF file
Eetu HeikkiläEetu Heikkilä
Eetu Heikkilä
TVTero Välisalo
Tero Välisalo
RTRisto Tiusanen
Risto Tiusanen
JSJanne Sarsama
Janne Sarsama
MRMinna Räikkönen
Minna Räikkönen
Wave power is a potential technology for generating sustainable renewable energy. Several types of wave energy converters (WECs) have been proposed for this purpose. WECs operate in a harsh maritime environment that sets strict limitations on how and when the device can be economically and safely reached for maintenance. Thus, to ensure profitable energy generation over the system life cycle, system reliability is a key aspect to be considered in WEC development. In this article, we describe a reliability analysis approach for WEC development, based on the use of reliability block diagram (RBD) modelling. We apply the approach in a case study involving a submerged oscillating wave surge converter device concept that utilizes hydraulics in its power take-off system. In addition to describing the modelling approach, we discuss the data sources that were used for gathering reliability data for the components used in a novel system concept with very limited historical or experimental data available. This includes considerations of the data quality from various sources. As a result, we present examples of applying the RBD modelling approach in the context of WEC development and discuss the applicability of the approach in supporting the development of new technologies.

1 March 2023 in Scientific Journal of Gdynia Maritime University
Verified
Journal Article
Open access
Eetu HeikkiläEetu Heikkilä
Eetu Heikkilä
TMTimo Malm
Timo Malm
JSJanne Sarsama
Janne Sarsama
RTRisto Tiusanen
Risto Tiusanen
TAToni Ahonen
Toni Ahonen
Increasing automation is a major trend in container terminals. In automated container handling systems, safety has been previously ensured by segregating the automated machinery from other traffic and workers moving on foot. Currently, further increases in flexibility are sought by developing autonomous systems that are capable of mixed-traffic operations without the need for separate operating areas. This increases the complexity of the systems and introduces new safety hazards. In addition to traditional hazard analysis methods, new approaches are needed to address the emergent risks related to autonomous operations. This paper studies the applicability of the STPA (system-theoretic process analysis) method in hazard analysis of an autonomous machine system. To support the evaluation, we define evaluation categories for comparison of the analysis methods. We also compare STPA with an established method, HAZOP (hazard and operability study). To perform the comparison, both STPA and HAZOP are applied to an autonomous container handling system concept. The study suggests that both STPA and HAZOP are well suited to support the development of autonomous machinery. However, we also highlight some notable differences in the methods, mostly related to the different underlying accident models that they utilise. HAZOP is an established method with tools and standards available. STPA, on the other hand, provides a well-defined syntax to ensure the analysis quality and a system modelling approach that supports the system development.

5 June 2017
Verified
Conference Paper
Closed access
Eetu HeikkiläEetu Heikkilä
Eetu Heikkilä
RTR Tuominen
R Tuominen
RTRisto Tiusanen
Risto Tiusanen
JMJakub Montewka
Jakub Montewka
PKP Kujala
P Kujala