Dr David J Purdy CEng, FIMechE

Senior Lecturer
Location: Shrivenham campus
E: d.j.purdy@cranfield.ac.uk
T: +44 (0) 1793 785352
Department of Engineering and Applied Science

Current activities

My main area of expertise is the dynamics of wheeled and tracked vehicles for on and off road. I believe in understanding the fundamental phenomena of the systems being investigated, generating designs that are close to optimal passively and enhancing their performance by the use of control techniques.

I specialise in problems relating to;

Wheeled and Tracked vehicle dynamics (ride/handling/stability)
Vehicle suspension configuration and design including adaptive/active elements
Improving vehicle performance in relation to ride
Vehicle testing
Novel vehicle configurations

These problems I solve using;

A combination of physical testing, modelling and simulation including real time implementation
Use of conventional and modern control techniques
Writing of specialist software
Optimisation methods

Additional areas covered

Specialist courses in;

Matlab and Simulink for Defence Related Problems

Whole Vehicle (Four Post), Suspension Component and Tyre testing

Modelling, simulation and testing of Gun/Weapon Control Systems

Snowboard and artificial snow surface design

Selected publications

Journals

Brooks, L. E. E., Purdy, D. J., and Edmonds, S., Modelling and experimental validation of an artificial snow surface, Journal of Mechanical Engineering Science (Part C), In press.

Leung, K.T., Whidborne, J., Purdy, D. and Dunoyer, A., A review of ground vehicle dynamic state estimations utilising GPS/INS, Vehicle System Dynamics, 2009.

Leung, K.T., Whidborne, J., Purdy, D. and Dunoyer, A., Ideal vehicle sideslip estimation using consumer grade GPS and INS, SAE International, 2009.

Purdy, D. J. Gun barrel models for use in weapon control system investigations, J. Battlefield Tech. Vol. 9, No. 1, March 2006.

Purdy, D. J. and Kumar, J. R., Mathematical modelling of a hydro-gas suspension unit for tracked military vehicles, J. Battlefield Tech. Vol. 8, No. 3, November 2005.

Purdy, D. J. and Simner, D., A Brief Investigation into the Effect on Suspension Motions of High Unsprung Mass, J. Battlefield Tech. Vol. 7, No. 1, March 2004.

Wormell, P. J. H. and Purdy, D. J., Handling of Tracked Vehicles at Low Speed, J. Battlefield Tech. Vol. 7, No. 1, March 2004.

Purdy, D. J. and Wormell, P. J. H., Handling of High-Speed Tracked Vehicles, J. Battlefield Tech. Vol. 6, No. 2, July 2003.

Pedchote, C. and Purdy, D.J., Parameter Estimation of a Quarter-Vehicle Suspension Using Hybrid Differential Evolution, Journal of Automobile Engineering (Part D) 2003, Vol. 217, pp 431-447.

Purdy, D. J., Theoretical Investigation into the Modelling of a Flexible Beam With Drive-Line Compliance, Journal of Mechanical Engineering Science (Part C), 2002, Vol. 216, pp 813-829.

Purdy, D. J., Theoretical and Experimental Investigation into an Adjustable Automotive Damper, Journal of Automobile Engineering (Part D), 2000, Vol. 214, pp 265-283.

Purdy, D. J. and Bulman, D. N., An Experimental and Theoretical Investigation into the Design of an Active Suspension System for a Racing Car, I.Mech.E., Journal of Automobile Engineering (Part D) 1997 Vol. 211 pp 161-173.

Conferences

Ahmed, F. and Purdy, D. J., Controller Design of Active Suspension System with Terrain Preview using Evolutionary Multi-Objective Algorithms, International conference on soft computing for problem solving, SocProS – 2011, Roorkee India, December 2011.

Purdy, D. J. and Stonier, C., Experimental and theoretical investigation into the rollover of tracked vehicles, 10th International Symposium on advanced vehicle control (AVEC10), Loughborough UK, 2010

Purdy, D. J. and Dias Torcato, R., Test signals for four and sever post rigs, FISITA World Automotive Conference, Budapest, 2010.

Purdy, D. J., Mehrishi, S. and Berrouila, L., Design and implementation of an active suspension system with terrain preview, FISITA World Automotive Conference, Budapest, 2010.

Brooks, L. E. E. and Purdy, D. J., Advanced snowboard design (modelling and testing), NAFEMS UK Engineering Simulation Conference, Oxford, 2010.

Leung, K.T., J. Whidborne, D. Purdy, A. Dunoyer and R. Williams, A study on the effects of GPS accuracy on a GPS/INS Kalman fillter, Proceedings of UKACC International Conference on Control, Manchester, UK, 2008.

Purdy, D. J., An Investigation into the Modelling and Stability of High Speed Tracked Vehicles, FISITA World Automotive Congress, Yokohama, October 2006.

Purdy, D. J., Development of a Six Degree of Freedom Tracked Vehicle Model, The 18th International Conference on Systems Engineering, Coventry, September 2006.

Purdy, D. J., Comparison of Balanced and Out Of Balance Main Battle Tank Armaments, The 9th US Army Symposium on Gun Dynamics, McLean, VA, November 1998.