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Three types of thin, flexible force sensor were studied under a variety of loading conditions to determine their suitability for measuring grip force. Static accuracy, hysteresis, repeatability, and drift errors were established, the effects of shear force and surface curvature were considered, and dynamic accuracy and drift were measured. Novel tests were developed to consider dynamic accuracy and sensitivity to shear loadings. Additionally, three sensors were evaluated in a real-life gripping scenario, measuring grip force during a golf shot. Comments are made on sensor performance, ease of use, and durability.

Assessment of sports equipment 'performance' is generally derived from physical and technical parameters, such as power, speed, distance and accuracy. However, from a psychological perspective, players need to feel comfortable with their equipment and confident in its properties. These factors can only be measured via the subjective assessment of individual perceptions. Using a study of a group of elite golfers as an example, this paper presents a formalised approach for eliciting and structuring player's descriptions of their perception of sports equipment. Qualitative methods of inquiry are employed to generate perceptions from a group of professional golfers (n=15) during play testing. The equipment characteristics of significance to the golfers emerged from an inductive analysis of their responses. However, whilst this method of representation of the results was invaluable in identifying the key components or dimensions of a player's subjective perception, it was insufficient to describe the potential relationships between the dimensions. With this in mind, a new technique, entitled structured relationship modelling, was developed to illustrate these associations. Ten general dimensions emerged from the analysis, of which three are presented in this paper along with a section of the relationship model. These results demonstrate the effectiveness of qualitative techniques for eliciting human perceptions and of structured relationship models for representation of the associations found.

This totally general velocity sensitivity model can be applied to any measurement configuration on any target. The model is also sufficiently versatile to incorporate time dependent beam orientation and this is described in this paper, with reference to continuous scanning Laser Doppler Vibrometry. For continuous scanning applications, the velocity sensitivity model is shown formulated in two useful ways. The first is in terms of the laser beam orientation angles, developing the original model to include time dependency in the angles, whilst the second is an entirely new development in which the model is written in terms of the mirror scan angles, since it is these which the operator would seek to control in practice.In the original derivation, the illuminated section of the rotating target was assumed to be of rigid cross-section but, since continuous scanning measurements are employed on targets with flexible cross-sections, such as beams, panels and thin or bladed discs, the theory is developed in this paper for the first time to include provision for such flexibility.

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