AdaptiveImpact Absorption Jan Holnicki-Szulc Institute of Fundamental Technological Research Smart Technology Centre http://smart.ippt.gov.pl
Smart Technology Centre: 25 researchers (Smart Technologies for Structural Safety) *AIA Adaptive Impact Absorption *SHM *Vibration Control *Vibroacoustics
ADLAND Adaptive Landing Gears for Improved Impact Absorption (IST-FP6-Aero1-502793-STREP) Consortium: IFTR PAS EADS PZL Mielec IA CEDRAT FhG-ISC USFD MD
Established methodology General algorithm Mhodology 1. Impact parameters identification formulation 1. Weight on the particular struts 2. Sink speed of the struts (independent sensor per each strut in order to obtain the accurate aircraft position vs runway) 2. Adequate control strategy application optimal damping force and stroke determination 3. Control process execution
Problems & challenges Control execution time: Problems & Fast actuator challenges Fast driving electronics Fast controller Fast sensing system for the data feeding of the controll system Accurate measuring of the sink speed ultrasonic sensor design Monitoring of the exact position of the aircraft in reference to the runway
Conducted research New landing gear design & manufacture Piezo-valve vs. MRF-based landing gear Magnetorheological fluid development Control system Sensing system Problems & challenges
New landing gear design & manufacture Problems & challenges
Piezo-valve and MRF-based landing gear prototypes Problems & challenges
Control system Trigger Fast Current Generation Disturbances Problems & challenges Force level Force Control Algorithm A Current Control Algorithm Supplier Fast Current Output MRD System Sensor Feedback Force sensor Sensor Feedback Fast control signal generation
Sensing system H = i ct 2 i R Problems & challenges V i = H i H T i 1 reflected wave H i transmitted ultrasonic wave
Testing sequence Laboratory scale test stand Experimental testing Full scale test stand Field testing
Laboratory scale testing RealTime_PC - DAQ Lab Stand x M d Experimental testing 1 k t FPGA unit x 2 k p c v k pd CURRENT AMPLIFIER
Laboratory testing results 30% 2500 2000 Controlled drop test 54kg non adapted adapted controlled Experimental testing 1500 Force [N] 1000 500 0-500 -50 0 50 100 150 200 250 300 350 400 Displacement [mm x10]
Full scale testing Experimental testing
Full scale testing results Fz [dan] 1500 1400 1300 1200 1100 1000 I23 NOSE LANDING GEAR - SHOCK ABSORBER WITH PIEZO-VALVE ADLAND pz172 pz107 Fz = f(t) U = 0 [V] const. pz105 H = 100 [mm] pz107 H = 200 [mm] U controled pz155 H = 100 [mm] pz172 h = 200 [mm] Experimental testing 900 800 700 600 500 400 300 200 100 0-100 pz155 pz105 0.60 0.70 0.80 t [s]
Field testing planned for 27.06.2006 Experimental testing
Adaptive Impact Absorption -other potential applications AIA for land transportation adaptive train buffers protective road barriers AIA for water transport applications safe docking systems (esp. in open, rough sea) AIA for reduction of damages caused by collisions Wind turbines Tall masts
UpWind - FP6-2004-Energy-3 IP task 1B3.7 (2006-2011) Main objectives: semi-active devices to mitigate vibrations k, c c,k Simulations and feasibility studies of systems with controllable stiffness and damping Development of control strategies to optimize the damping effect Hardware using MR fluid, piezo-valves or other Sensor system allowing for real-time adaptation span wise distributed, active pitch control system Local deformation of aerofoil, moveable surfaces or other means to control air flow locally Control strategies to reduce aeroelastic forces Sensor system allowing for real-time adaptation
Wind blows adaptation initial ideas (1) experimental demonstrator max F dyn < F crit pneumatic system used as smart interface piezo controlled valve as actuator cylinder pressure transducer as sensor
Wind blows adaptation initial ideas (2) numerical results
Wind blows adaptation initial ideas (3) pneumatic piston Further steps add Bruel & Kjaer surface microphone as loading sensor make closed loop between loading real time monitoring and the controllable valve Blover Additional surface B&K sensor
Tall Mast AIA -1 Monitored node Active elements equipped with structural fuses: adjustable yield stress value in the element Energy is dissipated in 1 semi-active zone Active elements 6 m 1000 kg Objective function for the controlled node: Minimise the maximal value of the horizontal acceleration min f f = max { q&& t } t cntrl ( ) 6m V0 = 8 m/s Impact index 1 T cntrl T t = 1 ( ) I = q && t
Elastic response Uniform yield stress 6e8Pa I = 2642 f = 3150 Displacement for the elastic and optimal solution Plastic response Yield stress: 1e8Pa Zone 1: 3.6e7 I = 180 f = 808 Optimal solution Acceleration for the elastic and plastic solution Yield stress: 6e8Pa Zone 1: 3.6e7 I = 40 f = 487 Acceleration for the elastic and optimal solution
Monitored node Tall Mast, AIA- 2 Crs. Sect.A gravity Energy is dissipated in 4 semi -active zones Active elements equipped with structural fuses: adjustable yield stress value in the element Active Zone 4 Active Zone 3 500 kg Objective function for the controlled node: Minimise the maximal value of the horizontal acceleration Crs. Sect.5A Active Zone 2 Active Zone 1 4 m 4m V0 = 8 m/s 500 kg min f f = max { q&& t } Impact index 1 T cntrl T t = 1 t ( ) I = q && t cntrl ( )
Elastic response Optimal solution elk.gnp" Structural failure Uniform yield stress 6e8Pa I = 2642 f = 7980 Yield stress: 6e8Pa Zone 1: 5.0e6 Zone 2: 6.0e6 Zone 2: 3.0e6 Zone 2: 6.0e5 I = 40 f = 587
Optimal Results Acceleration for the elastic and optimal solution Acceleration for the optimal solution
Optimal Results Displacement for the elastic and optimal solution Evolution of the kinetic and plastic strain energy for the optimal solution
Process of Adaptive Impact Absorption Identify the impact Choose the best strategy Adapt active elements according to the strategy Dissipate the energy of the impact Perform structural recovery
Structural Recovery - Self Repairing Structure Low level vibrations induced in the structure Elastic response Structural fuses in active elements If the sign of the residual strain is compatible with elastic strain: OPEN CLOSED CLOSED OPEN CLOSED
Thank you for your attention http://smart.ippt.gov.pl holnicki@ippt.gov.pl