• Research topic, the global picture
• During my research, I investigate mechanical systems, where the known velocity directions play key role. Within this area, I focus on those systems where the human factor also appears, e.g. the human tries to control. Skateboarding or car driving, what is a popular research topic recently, can be efficiently modelled as human controlled non-holonomic systems.
• My research in key words

• Analytical mechanics Dynamics Non-holonomic systems Control Human control

  Stability analysis Time-delay systems Time-varying systems Finite-time Lyapunov exponent

• Skateboarding
• Since my bachelor thesis work, I deal with the description of the motion of skateboards. It has several similar aspect with biking, e.g. it is difficult to ride on a bicycle at low speed, but it gets easier at higher speed. In case of skateboarding, there are some similar effect, but clearly at even higher speeds it is really dangerous to ride on a board. This is the reason, why we call it extreme sport. The description of this phenomenon is challenging from both engineering and theoretical point of view. Moreover, the proper description of skateboard's motion brings us closer to the understanding how the human balancing works, what may help us to understand the human brain itself.
• Vehicle manoeuvrability
• Another similarly inspiring question is that how can we keep the straight line motion of a car. What should we do, when suddenly an accident avoiding manoeuvre is required and it is not allowed to leave the road. This situation can be even more complicated, if the car accelerates or deaccelerates. A similar question arises in case of truck-trailer or semi-trailer systems. Here the high speed is not even necessary to cause problems with parking, especially in reverse motion.
  In this case we can ask, how the reflex delay of the driver influences the performed task's feasibility. Another key point is the selection of the appropriate control strategy to get home safely.
• Publications

• Dissertations
  MSc
  • Varszegi B.: The effect of time delay in skateboard balancing, 2014, Supervisors: Takacs D., Hogan S.J.
  • Varszegi B.: A tőkefelhalmozás időbelisége és a gazdasági növekedés kapcsolata, 2015,
    Supervisor: Domi A.
  Journal papers
  2019
  • Várszegi B., Takács D., & Orosz G.: On the nonlinear dynamics of automated vehicles–A nonholonomic approach. European Journal of Mechanics-A/Solids , 74, 371-380. (2019)
    doi: 10.1016/j.euromechsol.2018.11.015
  2018
  • Varszegi B., Takacs D., Insperger T.: Acceleration helps in skateboarding at high speeds, International Journal of Dynamics and Control 6(3):982–989, (2018) doi: 10.1007/s40435-017-0368-9.
  2017
  • Varszegi B., Takacs D., Stepan G.: Stability of damped skateboards under human control, ASME Journal of Computational and Nonlinear Dynamics, 12(5):051014-051014-7 (2017) doi: 10.1115/1.4036482.
  2016
  • Varszegi B., Takacs D., Stepan G., Hogan S. J.: Stabilizing skateboard speed-wobble with reflex delay, Journal of the Royal Society Interface 13, 20160345, (2016) doi: 10.1098/rsif.2016.0345.
  • Varszegi B., Takacs D.: Downhill Motion of the Skater-Skateboard System, Periodica Polytechnica Mechanical Engineering 60(1), pp. 58-65, (2016) doi: 10.3311/PPme.8636
  Conference papers
  2018
  • Varszegi B.: On the convergence and the steady state in a delayed Solow model In Proceedings of 14th IFAC Workshop on Time Delay Systems (IFAC-TDS 2018), Accepted manuscript, June 28 – 30, 2018, Budapest, Hungary
  • Vörös I., Varszegi B.: Lateral Vehicle Control Using Finite Spectrum Assignment In Proceedings of 14th IFAC Workshop on Time Delay Systems (IFAC-TDS 2018), Accepted manuscript, June 28 – 30, 2018, Budapest, Hungary
  2017
  • Berezvai Sz., Lehotzky D., Molnar T., Varszegi B., Antali M., Sykora H.: Lehetőségek és motiváció doktorandusz szemmel In Proceedings of XIII. Mechanikát Oktatók Hazai Rendezvénye (MOHR), pp 9-11, August 29 – 30, 2017, Szeged, Hungary
  • Vörös I., Varszegi B.: Sávváltás prediktív modell alapú szabályozása In Proceedings of 25th Nemzetközi Gépészeti Konferencia (OGÉT 2017), pp 476 - 479, April 27 – 30, 2017, Cluj-Napoca, Romania
  2016
  • Varszegi B., Takacs D.: Emberi egyensúlyozás gördeszkán In Proceedings of 12th Tavaszi Szél Konferencia, April 15-17, 2016 Budapest, Hungary, pp. 1-11
  2015
  • Varszegi B., Takacs D., Stepan G.: Skateboard: a human controlled nonholonomic system In Proceedings of ASME 2015 International Design Engineering Technical Conferences & Computers and Information in Engineering Conference (IDETC/CIE 2015), August 2-5, 2015, Boston, Massachusetts, USA, pp. 1-6 doi: 10.1115/DETC2015-47512
  • Varszegi B., Takacs D., Stepan G.: Position Control of Rolling Skateboard In Proceedings of 12th IFAC Workshop on Time Delay Systems (IFAC-TDS 2015) June 28-30, 2015, Ann Arbor, Michigan, USA, pp. 286-291, doi: 10.1016/j.ifacol.2015.09.392
  • Varszegi B., Takacs D., Hogan S. J.: A gördeszkázás Dinamikája In Proceedings of XII. Magyar Mechanikai Konferencia August 25-27, 2015, Miskolc, Hungary, pp 1-6
  2014
  • Varszegi B., Takacs D., Stepan G., Hogan S. J.: Balancing of the skateboard with reflex delay In Proceedings of 8th Europien Nonlinear Dynamics Conference (ENOC 2014), July 6-11, 2014, Vienna, Austria, pp. 1-6
  Conference posters
  2014
  • Varszegi B., Takacs D., Stepan G., Hogan S. J.: Reflex delay influenced stability of skateboarding Investigating Dynamics in Engineering and Applied Science (IDEAS), Julay 3-5, 2014, Budapest, Hungary
  Conference abstracts
  2017
  • Varszegi B., Takacs D., Insperger T.: Balancing on accelerating skateboard, Extended Abstract; 9th Europien Nonlinear Dynamics Conference (ENOC 2017) ISBN 978-963-12-9168-1, ID 430, June 25 – 30, 2017, Budapest, Hungary
  • Varszegi B., Takacs D.: Gördeszkázás nehézségei változó sebesség mellett, Accepted Abstract; 13th Tavaszi Szél Konferencia, March 31 – April 2, 2017, Miskolc, Hungary

Copyright © 2018 Balázs Várszegi