TY  - JOUR
A1  - Wittmann, Klaus
A1  - Feuerbacher, B.
A1  - Ulamec, S.
A1  - Rosenbauer, H. (u.a.)
T1  - Rosetta Lander - In Situ Characterisation of a Comet Nucleus
JF  - Acta Astronautica. 45 (1999), H. 4-9
Y1  - 1999
SN  - 0094-5765
SP  - 389
EP  - 395
ER  - 
TY  - JOUR
A1  - Wittmann, Klaus
A1  - Bibring, J.-P.
A1  - Rosenbauer, H.
A1  - Boehnhardt, H.
T1  - The Rosetta Lander (“Philae”) Investigations  / Bibring, J.-P. ; Rosenbauer, H. ; Boehnhardt, H. ;  [...] Wittmann, K.
JF  - Space Science Reviews. 128 (2007), H. 1-4
Y1  - 2007
SN  - 0038-6308
SP  - 205
EP  - 220
ER  - 
TY  - JOUR
A1  - Wittmann, Klaus
A1  - Bewersdorff, A.
A1  - Görler, G.P.
A1  - Otto, G.
T1  - Solidification of silver-germanium alloys in an amorphous matrix aboard the space station Mir
JF  - Acta Astronautica. 29 (1993), H. 7
Y1  - 1993
SN  - 0094-5765
SP  - 547
EP  - 552
ER  - 
TY  - JOUR
A1  - Wittmann, Klaus
T1  - The microgravity User Support Centre
JF  - Space Technology - Industrial and Commercial Applications. 13 (1993), H. 2
Y1  - 1993
SN  - 0892-9270
SP  - 121
EP  - 124
ER  - 
TY  - JOUR
A1  - Wittmann, Klaus
T1  - Overview of Space Operations at DLR
Y1  - 2000
N1  - SpaceOps2000 Conference, Toulouse, Frankreich,19-23 June 2000
ER  - 
TY  - CHAP
A1  - Wittig, M.
A1  - Rütters, René
A1  - Bragard, Michael
ED  - Reiff-Stephan, Jörg
ED  - Jäkel, Jens
ED  - Schwarz, André
T1  - Application of RL in control systems using the example of a rotatory inverted pendulum
T2  - Tagungsband AALE 2024 : Fit für die Zukunft: praktische Lösungen für die industrielle Automation
N2  - In this paper, the use of reinforcement learning (RL) in control systems is investigated using a rotatory inverted pendulum as an example. The control behavior of an RL controller is compared to that of traditional LQR and MPC controllers. This is done by evaluating their behavior under optimal conditions, their disturbance behavior, their robustness and their development process. All the investigated controllers are developed using MATLAB and the Simulink simulation environment and later deployed to a real pendulum model powered by a Raspberry Pi. The RL algorithm used is Proximal Policy Optimization (PPO). The LQR controller exhibits an easy development process, an average to good control behavior and average to good robustness. A linear MPC controller could show excellent results under optimal operating conditions. However, when subjected to disturbances or deviations from the equilibrium point, it showed poor performance and sometimes instable behavior. Employing a nonlinear MPC Controller in real time was not possible due to the high computational effort involved. The RL controller exhibits by far the most versatile and robust control behavior. When operated in the simulation environment, it achieved a high control accuracy. When employed in the real system, however, it only shows average accuracy and a significantly greater performance loss compared to the simulation than the traditional controllers. With MATLAB, it is not yet possible to directly post-train the RL controller on the Raspberry Pi, which is an obstacle to the practical application of RL in a prototyping or teaching setting. Nevertheless, RL in general proves to be a flexible and powerful control method, which is well suited for complex or nonlinear systems where traditional controllers struggle.
KW  - Rotatory Inverted Pendulum
KW  - MPC
KW  - LQR
KW  - PPO
KW  - Reinforcement Learning
Y1  - 2024
SN  - 978-3-910103-02-3
U6  - http://dx.doi.org/10.33968/2024.53
N1  - 20. AALE-Konferenz. Bielefeld, 06.03.-08.03.2024.
(Tagungsband unter https://doi.org/10.33968/2024.29)
SP  - 241
EP  - 248
PB  - le-tex publishing services GmbH
CY  - Leipzig
ER  - 
TY  - BOOK
A1  - Witte, Bertold
A1  - Sparla, Peter
T1  - Vermessungskunde und Grundlagen der Statistik für das Bauwesen
Y1  - 2011
SN  - 978-3-87907-497-6
PB  - Wichmann
CY  - Heidelberg
ET  - 7., überarb. erw. Aufl.
ER  - 
TY  - JOUR
A1  - Witt, Klaus
A1  - Bogner, D.
T1  - Druckmessung mit zukunftsorientierten Perspektiven
JF  - Sensor Report. 5 (1990), H. 1
Y1  - 1990
SN  - 0179-9592
SP  - 8
EP  - 14
ER  - 
TY  - JOUR
A1  - Wissenbach, U.
A1  - Six, S.
A1  - Bongaerts, Johannes
A1  - Ternes, D.
A1  - Steinwachs, S.
A1  - Unden, G.
T1  - A third periplasmic transport system for l-arginine in Escherichia coli: molecular characterization of the artPIQMJ genes, arginine binding and transport
JF  - Molecular microbiology
Y1  - 1995
SN  - 1365-2958 (E-Journal); 0950-382x (Print)
VL  - Vol. 17
IS  - Iss. 4
SP  - 675
EP  - 686
ER  - 
TY  - JOUR
A1  - Wissen, M.
A1  - Bogdanski, N.
A1  - Scheer, H.-C.
A1  - Bitz, Andreas
A1  - Ahrens, G.
A1  - Gruetzner, G.
T1  - Implication of the light polarisation for UV curing of pre-patterned resists
JF  - Microelectronic Engineering
Y1  - 2005
U6  - http://dx.doi.org/10.1016/j.mee.2004.12.099
SN  - 0167-9317
VL  - 78-79
SP  - 659
EP  - 664
ER  -