29.06.2021
Time-optimal fold-out of a mobile concrete pump

Project description

Mobile concrete pumps are used on construction sites to transport concrete from the cement mixer to the formwork. Such machines typically comprise a pump and a boom equipped with concrete convey pipes, see Fig. 1. To enable a large operating range (up to approx. 60m) while being able to transport the boom on a standard truck, the boom of these mobile concrete pumps is constructed in a lightweight design. Due to the complex kinematics with up to 6 individual joints and the large working areas, an optimal manual operation by a human operator is cognitively not possible.

In the current state of the art the actuator velocities of such manipulators are heavily limited to ensure safe operation. The complex motion of folding out the boom is performed sequentially by simultaneously movement of maximum 2-3 joints. Furthermore well experienced operating staff is required. The trend in the off-highway sector shows a significant increase in more complex assistance systems in the last years, helping the operating staff actively concerning user comfort and increased safety during autonomous operation.

Project focus

In this research project, a system is developed to obtain time-optimal, collision-free motions of the boom of a mobile concrete pump. The resulting trajectories for the joint angles consider the technical limitations of the joint angles and joint angular velocities as well as legal restrictions concerning Cartesian velocities. Furthermore, if the support feet of the machine are not fully extended (e.g. due to limited space on site), the working area of the manipulator is systematically limited. The developed concept is tested and validated on a real machine with 5 individual rotational joints.

Selected publications

• J. Henikl, W. Kemmetmüller, and A. Kugi, Estimation and control of the tool center point of a mobile concrete pump, Automation in Construction, vol. 61, p. 112–123, 2016.
  [BibTex] [Download]

  @Article{Henikl16,
  Title = {Estimation and control of the tool center point of a mobile concrete pump},
  Author = {Henikl, J. and Kemmetm\"uller, W. and Kugi, A.},
  Journal = {Automation in Construction},
  Pages = {112--123},
  Volume = {61},
  Year = {2016},
  Doi = {10.1016/j.autcon.2015.10.005},
  ISSN = {0926-5805},
  }

• J. Henikl, W. Kemmetmüller, T. Meurer, and A. Kugi, Infinite-dimensional decentralized damping control of large-scale manipulators with hydraulic actuation, Automatica, vol. 63, p. 101–115, 2016.
  [BibTex] [Download]

  @Article{Henikl16a,
  Title = {Infinite-dimensional decentralized damping control of large-scale manipulators with hydraulic actuation},
  Author = {Henikl, J. and Kemmetm\"uller, W. and Meurer, T. and Kugi, A.},
  Journal = {Automatica},
  Pages = {101--115},
  Volume = {63},
  Year = {2016},
  Doi = {10.1016/j.automatica.2015.10.024},
  ISSN = {0005-1098},
  }

• J. Henikl, W. Kemmetmüller, M. Bader, and A. Kugi, Modeling, Simulation and Identification of a Mobile Concrete Pump, Mathematical and Computer Modelling of Dynamical Systems, vol. 21, iss. 2, p. 180–201, 2015.
  [BibTex] [Download]

  @Article{Henikl14,
  Title = {Modeling, Simulation and Identification of a Mobile Concrete Pump},
  Author = {Henikl, J. and Kemmetm\"uller, W. and Bader, M. and Kugi, A.},
  Journal = {Mathematical and Computer Modelling of Dynamical Systems},
  Pages = {180--201},
  Volume = {21},
  Year = {2015},
  Number = {2},
  Doi = {10.1080/13873954.2014.926277},
  }

• M. Meiringer, A. Kugi, and K. W., Time-optimal fold out of large-scale manipulators with obstacle avoidance, in Proceedings of the 11th IFAC Symposium on Nonlinear Control Systems NOLCOS 2019, Vienna, Austria, 2019, pp. 114-119.
  [BibTex]

  @InProceedings{Meiringer2019,
  author = {Meiringer, M. and Kugi, A. and Kemmetm\"uller W.},
  title = {Time-optimal fold out of large-scale manipulators with obstacle avoidance},
  booktitle = {Proceedings of the 11th IFAC Symposium on Nonlinear Control Systems NOLCOS 2019},
  year = {2019},
  volume = {52},
  number = {16},
  month = {9},
  pages = {114-119},
  doi = {10.1016/j.ifacol.2019.11.765},
  address = {Vienna, Austria},
  issn = {2405-8963},
  }

• W. Kemmetmüller, M. Meiringer, V. Platzgummer, and A. Kugi, Optimale Abstützung eines mobilen Großraummanipulators, at – Automatisierungstechnik, vol. 69, iss. 9, p. 782–794, 2021.
  [BibTex]

  @Article{Kemmetmueller2021,
  author = {Wolfgang Kemmetmüller and Martin Meiringer and Valentin Platzgummer and Andreas Kugi},
  title = {Optimale Abstützung eines mobilen Großraummanipulators},
  doi = {doi:10.1515/auto-2021-0052},
  number = {9},
  pages = {782--794},
  url = {https://doi.org/10.1515/auto-2021-0052},
  volume = {69},
  journal = {at -- Automatisierungstechnik},
  year = {2021},
  }

• M. Meiringer, A. Kugi, and W. Kemmetmüller, Modelling and calibration of a five link elastic boom of a mobile concrete pump, Mathematical and Computer Modelling of Dynamical Systems, vol. 29, iss. 1, p. 41–68, 2023.
  [BibTex] [Download]

  @Article{Meiringer2023,
  author = {M. Meiringer and A. Kugi and W. Kemmetm\"uller},
  title = {Modelling and calibration of a five link elastic boom of a mobile concrete pump},
  doi = {10.1080/13873954.2023.2177311},
  number = {1},
  pages = {41--68},
  volume = {29},
  journal = {Mathematical and Computer Modelling of Dynamical Systems},
  year = {2023},
  }

• M. Meiringer, A. Kugi, and W. Kemmetmüller, Semi-autonomous operation of a mobile concrete pump, Automation in Construction, vol. 156, p. 105079, 2023.
  [BibTex]

  @Article{Meiringer2023a,
  author = {Meiringer, M. and Kugi, A. and Kemmetm\"uller, W.},
  title = {Semi-autonomous operation of a mobile concrete pump},
  doi = {10.1016/j.autcon.2023.105079},
  pages = {105079},
  volume = {156},
  journal = {Automation in Construction},
  year = {2023},
  }

  02.06.2021
High-speed large format 3D printing

Project focus

• Development of a high speed polygon mirror based SLA 3D-printer
• Opto-mechatronic system design for maximum performance
• Characterization of polygon mirrors
• Correction methods for high resolution printing

Description

Additive manufacturing (AM) constantly gains in importance in the manufacturing industry. Compared to classical manufacturing technologies, it offers many advantages such as almost unlimited design freedom, direct manufacturing of parts from CAD models and affordable manufacturing even at low quantities. Furthermore, parts can be produced with minimum excessive material consumption compared to conventional manufacturing methods. This leads to a significantly reduced ecological footprint of AM. State of the art industrial printers, which achieve high resolution and accuracy, are based on the stereolithography (SLA) principle in combination with Galvanometer beam steering, which scan a laser spot over a resin surface for photopolymerization. Scanning speeds between 2 m/s and 30 m/s are typical and limited by the scanner dynamics, such that medium and large part counts are not economically achievable. By speeding up the manufacturing processes this limitation can be circumvented, enabling additive mass production.

Approach

In order to increase the printing speed and volume without impairing the achievable resolution, an integrated opto-mechatronic system design is applied in this project. In the development of the optical scanning unit, not only conventional galvanometer scanners, but also other scanners such as fast steering mirrors and polygon scanners will be considered. Such components will be synthesized to complement each other, where their interaction will be explicitly considered. Control algorithms of the synthesized system will be selected and designed by considering the underlying physical phenomena, such as mechanical dynamics and photochemical dynamics for the highest possible performance.

Schematic setup of the polygon mirror based SLA 3D-printer. The light engine, which consists out of a laser stabilizing mirror and the polygon scanner, is moved by two linear motors.[/caption]

Videos

• Development of a 3D-SLA printer using a polygonal mirror

Project Partners

• Cubicure GmbH

Funding

• FFG – Die Österreichische Forschungsförderungsgesellschaft
• The Austrian Federal Ministry for Digital and Economic Affairs

  19.04.2021
AC-KPFM

Project goals

• Development of electrical Atomic Force Microscopy (AFM) modes – KPFM
• Sensing electrical charge distributions at the nanoscale in aqueous environment
• In-vitro observations of biological cells

Description

Many fundamental processes in nature rely on the interaction between surface charges at the nanoscale, whether it is about functionalization of a materials surface to make it more durable (corrosion resistant) or the interaction of a biological cells with its environment. Surface charges play a key role in such cases, as they drive electrostatic forces which have direct impact on the behaviour of the carrier. With the ability to measure the local surface potential distribution on cells in their natural environment, one could investigate the influence of specific treatments on the systems behaviour.

This project aims towards the development of electric Atomic Force Microscopy modes for quantitative charge distribution measurements in liquids, or more specific, aqueous solutions with varying ionic concentration. To this end, studies are carried out regarding the formation of electric double layers (EDLs), movement of solvated ions and influence of measurement parameters (electrical drive frequencies,…).

Use cases

• In-vitro studies of biological cells or corrosion processes
• Research applications in biological / material sciences

Related Publications

• D. Kohl, P. Mesquida, and G. Schitter, Quantitative DC-free Kelvin Probe Force Microscopy, in Final Program 42nd International Conference on Micro and Nano Engineering, 2016.
  [BibTex]

  @InProceedings{TUW-254059,
  Title = {Quantitative DC-free Kelvin Probe Force Microscopy},
  Author = {Kohl, Dominik and Mesquida, Patrick and Schitter, Georg},
  Booktitle = {Final Program 42nd International Conference on Micro and Nano Engineering},
  Year = {2016},
  Note = {Vortrag: Micro and Nano Engineering 2016, VIenna; 2016-09-19 -- 2016-09-23},
  Doi = {10.1016/j.mee.2017.01.005},
  Numpages = {2}
  }

Project partner

• Physics Department, King’s College London (Dr. P. Mesquida)

Funding

• Austrian Science Fund (FWF) – Project No. P 31238-N28

  19.04.2021
Atomic Force Microscopy using self-sensing cantilevers

Description

In Atomic Force Microscopy (AFM), micro-cantilevers with a sharp tip are scanned over a sample to measure various surface properties with nanometer resolution. The measurement of the cantilever deflection is a crucial part, which defines the imaging performance of AFM. Self-sensing cantilevers with integrated piezoresistive or capacitive elements enable a direct and efficient deflection measurement and are a promising alternative to the conventional optical lever method. This project aims at enabling novel AFM methods and applications by exploiting the advantages of self-sensing cantilevers.

Integrated demodulation for dynamic measurement modes

In most AFM measurement modes, the cantilever is mechanically excited at its resonance frequency and the resulting oscillation is modulated by the tip-sample interaction forces. Therefore, the demodulation of the cantilever oscillation is required to obtain sample properties. Utilizing a piezoresistive detection scheme where the deflection is converted to a change of the electrical impedance, the demodulation can be integrated in the sensor electronics, which enables a simplified measurement of the oscillation.

Mechatronic system design for long-range high-bandwidth AFM

The application of AFM for in-line metrology requires large vertical motion of the AFM cantilever not only for high topography measurement, but also for compensation of sample height uncertainties (e.g. thermal expansion during AFM operation). However, the actuation range and control bandwidth of the cantilever’s vertical motion are restricted in a tradeoff, influenced by the actuation type and mover mass. Using integrated self-sensing cantilevers with small mass in combination with electromagnetic actuators and an optimized flexure design, a long-rage high-bandwidth AFM is developed.

Applications

• AFM for in-line metrology
• Compact and integrated AFM systems

Related Publications

• M. Poik, D. Kohl, M. Mayr, C. Kerschner, and G. Schitter, A Mechatronic Lock-In Amplifier: Integrating Demodulation in Sensor Electronics for Measuring Mechanical Oscillations, IEEE Transactions on Instrumentation and Measurement, vol. 70, pp. 1-8, 2021.
  [BibTex] [Download]

  @article{TUW-292319,
  author = {Poik, Matthias and Kohl, Dominik and Mayr, Mario and Kerschner, Christoph and Schitter, Georg},
  title = {A Mechatronic Lock-In Amplifier: Integrating Demodulation in Sensor Electronics for Measuring Mechanical Oscillations},
  journal = {IEEE Transactions on Instrumentation and Measurement},
  year = {2021},
  volume = {70},
  pages = {1-8},
  doi = {10.1109/TIM.2020.3047208},
  keywords = {Demodulation, Lock-In Amplifier, Resonant sensor, Cantilever, AFM}
  }

• M. Poik, D. Kohl, M. Mayr, C. Kerschner, and G. Schitter, Efficient Demodulation for Measuring the Amplitude of Mechanical Oscillations, in Proceedings of the IEEE International Instrumentation and Measurement Technology Conference (I2MTC 2020), 2020.
  [BibTex] [Download]

  @inproceedings{TUW-291330,
  author = {Poik, Matthias and Kohl, Dominik and Mayr, Mario and Kerschner, Christoph and Schitter, Georg},
  title = {Efficient Demodulation for Measuring the Amplitude of Mechanical Oscillations},
  booktitle = {Proceedings of the IEEE International Instrumentation and Measurement Technology Conference (I2MTC 2020)},
  year = {2020},
  numpages = {5},
  doi = {10.1109/I2MTC43012.2020.9129045},
  keywords = {Demodulation, Resonant sensor, Cantilever, AFM},
  note = {Vortrag: IEEE International Instrumentation and Measurement Technology Conference Proceedings I2MTC (2020), Dubrovnik, Kroatien; 2020-05-25 -- 2020-05-28}
  }

• S. Ito, M. Poik, J. Schlarp, and G. Schitter, Atomic Force Microscopy Breaking Through the Vertical Range-Bandwidth Tradeoff, IEEE Transactions on Industrial Electronics, 2020.
  [BibTex] [Download]

  @article{TUW-288567,
  author = {Ito, Shingo and Poik, Matthias and Schlarp, Johannes and Schitter, Georg},
  title = {Atomic Force Microscopy Breaking Through the Vertical Range-Bandwidth Tradeoff},
  journal = {IEEE Transactions on Industrial Electronics},
  year = {2020},
  numpages = {9},
  doi = {10.1109/TIE.2020.2982113},
  keywords = {Atomic force microscopy , Mechatronics , Nanopositioning , Precision engineering , Design for control}
  }

  19.04.2021
Sub-micrometer scanning probe based characterization of RF products on wafer-level (SuRF)

Project goals

• Development of a scanning probe based metrology system for sub-micrometer characterization and testing of RF semiconductor products
• Precision probe alignment and automation for in-device RF metrology
• Evaluation of millimeter-wave circuit characterization on device and wafer-level

Description

RF systems belong to the key components of modern technologies such as radar for environmental detection for safe automated driving through night and fog and Internet of Things devices like 5G telecommunication chips. State of the art RF probing systems have a limited spatial resolution due to large contact pads of conventional ground-signal-ground probes and cannot measure signals within the active area of the RF structures.

SµRF will address this shortcoming by developing a flexible and versatile RF microscopy system up to 90 GHz using conductive atomic force microscopy (AFM) cantilever, which facilitates precision down to nanometer scale. Advanced control and positioning algorithms with camera-based and optical AFM readout enable RF probing with automated probe alignment and nanoscale spatial resolution. The developed RF scanning probe system is verified on mmWave circuit devices (MMIC) and on wafer-level to validate the capability for production in-line metrology. The unique RF measurements enable design cycles to be reduced, chip size to be shrunk and improve RF and mmWave products to be designed with increased spatial precision.

Use case

• In-line metrology for production of radio frequency (RF) and millimeter wave (mmWave)
  semiconductor system-on-a-chip circuits like radar and 5G telecommunication

Project partner

• Infineon Technology Austria AG

Funding

• Production of Future, FFG – Austrian Research Promotion Agency
• Infineon Technology Austria AG

  15.04.2021
RF-AFM

Goals

• Development of contactless probing system for evaluation of integrated circuits
• Measurement of voltage distribution within RF-devices

Description

The accurate measurement of local RF-voltages within integrated circuits is crucial for the development of miniaturized electronic devices. Contactless probing techniques are considered a promising approach to overcome the space limitations imposed by the size of required contact pads used in conventional probing techniques. This project aims at developing a scanning probe based measurement system capable of mapping voltages within RF-devices with sub-um spatial resolution.

Scanning probe based microscopy systems are widely used for surface analysis in various research fields, such as biology, physics and material science. A small probe is scanned over the investigated sample to record surface properties with nanometer resolution. Due to its outstanding spatial resolution, this concept is employed for the measurement of voltages in highly integrated RF-devices in this project.

 

 

 

 

 

 

 

 

 

 

 

 

 

A small conducting probe is used as capacitively coupled sensor which is moved to individual circuit test points using high precision positioning stages. The measurement system can therefore be used for contactless evaluation of circuits without modifications of the layout. The small physical size of today’s RF-devices impose major challenges on the development of the system which have to be solved and will be addressed in this project.

To this end, a detailed analysis of the probe-circuit interaction is carried out using electrostatic and circuit simulations to identify the relevant trade-offs between sensitivity, spatial resolution and invasiveness, thus enabling the selection of suitable measurement parameters for achieving the best possible performance.

Applications

• Development and verification of RF-devices
• Failure analysis

Project Partners

• Infineon Technologies

  08.03.2021
Digital Literacy in Robotics & Informatics – for underprivileged people

Robotics and computer science are not imaginable without digital competence. Both are a possible entry into the digital world and promote the development of digital competence. However, the question also needs to be asked as to which barriers arise in the digital world and how these can be overcome. To this end, a working group with interdisciplinary members from different partner universities will be constituted to make common barriers visible and propose improvements for gender-appropriate didactic concepts.

Partners:

TU Wien ACIN Institut für Automatisierungs- und Regelungstechnik

TU Wien Department of Geodesy Geoinformation

FH Technikum Wien Digital Manufacturing & Robotics

FH Technikum Wien Informatik

Universität Wien, Institut für Bildungswissenschaften

Funding:

The Projectnumber is GEV376020CTS.

  19.02.2021
Versatile technology platform for MEMS scan system for automotive safety applications (AUTOScan)

Project focus

• Versatile technology for automotive MEMS mirror
• Sensing and Actuation for high performance MEMS scan systems
• Advanced control development for automotive qualified MEMS scan systems
• Feasibility evaluation of the MEMS scan system for automotive safety applications.

Description

Advancements of sensors, communication and artificial intelligence are about to bring a revolutionary changes in mobility and transportation by autonomous driving. Scanning mirrors based on Micro-Electro-Mechanical Systems (MEMS) technologies are one of the promising solutions for various automotive applications, e.g. photonic sensing such as lidars and human machine interfaces such as augmented reality head -up display (AR HUD) and smart headlights. Small form factor, high scanning performance and scalable low unit cost by mass production are raised as main advantages of the MEMS scanning solution for automotive applications. As a drawback, MEMS mirrors are prone to harsh operating conditions such as vibrations, shocks, and temperature variations, requiring highly robust system design with controls to guarantee their full device performance at any situation. However, it is challenging for analysis and control design since MEMS mirrors are highly nonlinear devices.

The AUTOScan project aims for automotive grade MEMS scanning systems for robust sensing and imaging in harsh automotive environmental conditions, enabling reliable MEMS lidars and AR HUDs. The research topics are categorized four aspects. First, precision metrology and automotive test setups for MEMS mirrors are developed to evaluate their performance under severe automotive conditions. Second, modeling and analysis of MEMS mirrors are investigated to understand its nonlinear dynamics. Third, sensing, actuation, and control concepts of MEMS scanning mirrors are studied for robust scanning motion in harsh environmental conditions. Last, test setups of lidars and AR display for automotive use are built to verify the performance in the final application level.

Applications

• Lidar for autonomous driving
• Augmented reality head up display
• Precision measurement systems

Related Publications and Patents

Journal articles

• R. Schroedter, H. W. Yoo, D. Brunner, and G. Schitter, Charge-Based Capacitive Self-Sensing With Continuous State Observation for Resonant Electrostatic MEMS Mirrors, Journal Of Microelectromechanical Systems, vol. 30, iss. 6, p. 897–906, 2021.
  [BibTex] [Download]

  @article{TUW-299022,
  author = {Schroedter, Richard and Yoo, Han Woong and Brunner, David and Schitter, Georg},
  title = {Charge-Based Capacitive Self-Sensing With Continuous State Observation for Resonant Electrostatic MEMS Mirrors},
  journal = {Journal Of Microelectromechanical Systems},
  year = {2021},
  volume = {30},
  number = {6},
  pages = {897--906},
  doi = {10.1109/JMEMS.2021.3107797},
  keywords = {Charge-based capacitive self-sensing , resonant MEMS mirror , electrostatic comb drive , switched current integrator , capacitance network , nonlinear switched input Luenberger observer}
  }

• D. Brunner, H. W. Yoo, R. Schroedter, and G. Schitter, Adaptive Lissajous scanning pattern design by phase modulation, Optics Express, vol. 29, iss. 18, p. 27989–28004, 2021.
  [BibTex] [Download]

  @article{TUW-296868,
  author = {Brunner, David and Yoo, Han Woong and Schroedter, Richard and Schitter, Georg},
  title = {Adaptive Lissajous scanning pattern design by phase modulation},
  journal = {Optics Express},
  year = {2021},
  volume = {29},
  number = {18},
  pages = {27989--28004},
  doi = {10.1364/OE.430171}
  }

• H. W. Yoo, D. Brunner, M. Macho, L. Niedermueller, A. J. Devesa, L. Kormann, and G. Schitter, Evaluation of robustness against external vibrations for long-range MEMS lidar with one-dimensional resonant micromirror, Journal of Optical Microsystems, vol. 2, iss. 1, 2022.
  [BibTex] [Download]

  @article{TUW-303700,
  author = {Yoo, Han Woong and Brunner, David and Macho, Matthias and Niedermueller, Leonhard and Devesa, Angel Jurado and Kormann, Leonhard and Schitter, Georg},
  title = {Evaluation of robustness against external vibrations for long-range MEMS lidar with one-dimensional resonant micromirror},
  journal = {Journal of Optical Microsystems},
  year = {2022},
  volume = {2},
  number = {1},
  doi = {10.1117/1.JOM.2.1.011007},
  keywords = {Microelectromechanical systems, LIDAR, Mirrors, Clouds, Receivers, Transmitters, Field programmable gate arrays, Optical microsystems, Video, Microcontrollers}
  }

News

• Control of MEMS lidar mirrors enables steady pictures in shaky environments
  

Project partners

• Infineon Technologies

Funding

This project (activity) has received funding from the Mobility of the Future programme. Mobility of the Future is a research, technology and innovation funding programme of the Republic of Austria, Ministry of Climate Action. The Austrian Research Promotion Agency (FFG) has been authorised for the programme management
• FFG Mobilität der Zukunft

  17.11.2020
PriMActO

Goals

• Development of a systematic system design for active optics.
• Development of a modular approach for the support strcture of the primary mirror.
• Construction of primary mirror cell for an 1 m mirror with active axial and lateral support.

Description

Currently, midsized telescopes with a diameter between 0,6 m and 2,0 m are gaining increased importance in several established as well as in newly emerging applications. Optical communication with satellites in the orbit, which enables more than ten times higher data rates than available radio frequency communication systems, and the identification and tracking of space debris, in order to reduce the risk for functional satellites, are two examples for applications requiring midsized robust telescope systems with sufficient light-gathering power as a fundamental prerequisite. To guarantee appropriate reliability of these systems, a large number of optical ground stations is required. This makes a low system mass of telescopes, allowing for easy transportation and installation, as well as low production costs a desirable property.

For reducing the weight of about 1500 kg and costs for production, transportation and installation of current, comparably heavy, telescopes in the 1-m class, thin lightweight mirrors can be employed to reduce the mass of the primary mirror, which is the driving factor for overall system cost and weight. To avoid a degradation of the imaging quality caused by deformations of the thin mirror due to gravity, this project aims to develop methods for the development and integration of an active optic system into the primary mirror cell of telescopes by the industrial partner ASA Astrosysteme GmbH in the 1-m class. The active optics enables to compensate for orientation dependent gravitational sag thermally induced deformations by an active correction of the mirror by using an active axial and lateral suspension system. Following an integrated mechatronic system design approach an extremely lightweight design, a high imaging quality of the system as well as an exceptional cost efficient solution are to be obtained. In this course, a modular concept for the system design will be developed, including methods for the optimal number and placement of actuators over the mirror surface and modular highly integrated actuator-sensor-systems. An optimal system integration systematically will consider the interplay between the system components, the system requirements and the real time control system and will enable the design of lightweight telescopes with highest optical quality.

Applications

• Satellite communication
• Space debris observation

Related Publications

• C. Schwaer, A. Sinn, P. Keller, and G. Schitter, Design methodology to develop an active optics system for a thin 1-m meniscus mirror, Journal of Astronomical Telescopes, Instruments, and Systems, vol. 6, iss. 4, p. 049002-1–049002-22, 2020.
  [BibTex] [Download]

  @article{TUW-291787,
  author = {Schwaer, Christian and Sinn, Andreas and Keller, Philipp and Schitter, Georg},
  title = {Design methodology to develop an active optics system for a thin 1-m meniscus mirror},
  journal = {Journal of Astronomical Telescopes, Instruments, and Systems},
  year = {2020},
  volume = {6},
  number = {4},
  pages = {049002-1--049002-22},
  doi = {10.1117/1.JATIS.6.4.049002},
  keywords = {active optics, telescopes, mirrors, lightweight design, finite element analysis, mechatronic system design}
  }

• C. Schwaer, A. Sinn, and G. Schitter, Mechatronic Approach towards Lightweight Mirrors with Active Optics for Telescope Systems, in Proceedings of the Joint Conference 8th IFAC Symposium on Mechatronic Systems (MECHATRONICS 2019), and 11th IFAC Symposium on Nonlinear Control Systems (NOLCOS 2019), 2019.
  [BibTex] [Download]

  @InProceedings{TUW-281662,
  author = {Schwaer, Christian and Sinn, Andreas and Schitter, Georg},
  title = {Mechatronic Approach towards Lightweight Mirrors with Active Optics for Telescope Systems},
  booktitle = {Proceedings of the Joint Conference 8th IFAC Symposium on Mechatronic Systems (MECHATRONICS 2019), and 11th IFAC Symposium on Nonlinear Control Systems (NOLCOS 2019)},
  year = {2019},
  volume = {52/15},
  note = {Vortrag: Joint Conference 8th IFAC Symposium on Mechatronic Systems (MECHATRONICS 2019), and 11th IFAC Symposium on Nonlinear Control Systems (NOLCOS 2019), Wien; 2019-09-04 -- 2019-09-06},
  doi = {10.1016/j.ifacol.2019.11.641},
  journal = {IFAC-PapersOnLine/Elsevier},
  keywords = {Active Optics, Meniscus Mirror, System Analysis, Optomechatronics},
  numpages = {6},
  }

Project partner

• ASA Astrosysteme GmbH

Funding

• ASAP 15, FFG – Die Österreichische Forschungsförderungsgesellschaft
• ASA Astrosysteme GmbH

  08.10.2020
Modelling and optimal control of a linear motor

Project focus

• Modeling of the linear motor
• Optimal currents for different use cases
• Development of a control concept for position control of one or more transport units

Description

The usage of long stator linear motors provides higher flexibility in a transport system for production plants compared to common conveyor belt systems. The usage of multiple transport units offers the advantage that the distances between the transport units, and thus the run-time of the transport process itself, can be freely chosen. In order to guarantee a high-dynamic operation it is necessary to obtain an accurate model of the motor and an optimal control strategy.

A main challenge when describing the behavior of electric machines are the systematic consideration of nonlinear magnetic material saturation and of nonlinear cogging forces along the transport motion. The modeling method chosen in this project uses magnetic equivalent circuits and allows a systematic derivation of a motor model, which is able to consider these phenomena. Based on the derived model, a optimal control problem is formulated, which yields optimal currents of the motor coils such that a given tractive and normal force is obtained for the transport units. Additionaly, existing efficiency constraints are taken into account for the calculated optimal currents. The positioning of one or multiple transport units is done using the calculated optimal currents. A further challenge arises from the task to guarantee positioning accuracy while moving multiple transport units within a very short distances between them.

Project partner

B&R Industrial Automation GmbH