Adding Light Touch While Walking in Older Adults: Biomechanical and Neuromotor Effects

Adding haptic input may improve balance control and help prevent falls in older adults. This study examined the effects of added haptic input via light touch on a railing while walking. Participants (N = 53, 75.9 ± 7.9 years) walked normally or in tandem (heel to toe) with and without haptic input. During normal walking, adding haptic input resulted in a more cautious and variable gait pattern, reduced variability of center of mass acceleration and margin of stability, and increased muscle activity. During tandem walking, haptic input had minimal effect on step parameters, decreased lower limb muscle activity, and increased cocontraction at the ankle closest to the railing. Age was correlated with step width variability, stride length variability, stride velocity, variability of medial-lateral center of mass acceleration, and margin of stability for tandem walking. This complex picture of sensorimotor integration in older adults warrants further exploration into added haptic input during walking.

Haptic input devices with intelligent signal processing ensuring process stability and quality management

As part of the Cluster of Excellence Merge, a complete process chain was developed for the production of a hybrid laminate with sensory function for continuous production processes. An interior surface of the VW UP! is a good example of this. In this work, the forming processes of the centre console and the parameters influencing quality are discussed. An important parameter for the polarisation of the sensor layer is the thickness of the piezoceramic foil after forming. The maximum signal quality can only be achieved by an exact prediction of the thinning of the foil during the forming process. In addition, the electrical characterisation, especially the capacitance, of the sensor areas is used to determine the foil thickness within the sensor areas in the complex-shaped centre console. Furthermore, a practicable polarisation strategy is deducted in consideration of thickness, electrical characteristics of the piezoceramic foil and process parameters of forming process. For evaluation a novel impact localisation method based on machine learning is shown. Special focus is put on the independence of the impact intensity in order to guarantee a user-independent operation. In this respect, the suitability of various intensity-independent localisation methods will be discussed and subsequently empirically evaluated.

Haptic input and balance control: An exploratory study examining normative messaging

This study examined the effect of descriptive norm messaging information on the relationship between haptic input and balance control. Participants were randomly assigned to either a message group where they balanced with haptic input after receiving a descriptive norm message about the positive effect of haptic input or a control group. Findings from an analysis of covariance revealed a significant difference between the two groups. Those in the descriptive norm message group had better balance control than those in the control group. These findings suggest that efforts designed to improve balance control through haptic input may be enhanced through normative messaging.

Novel Type of Biaxial Wheel-Type Haptic Input Device With MR-Brakes to Control Hydraulic Multi-Axis Manipulators

In the paper, authors present a design of a novel input device, in which, thanks to two ergonomically placed wheels, the operator can control the multi-axis manipulator with a single hand. The application of rotating elements provides the following benefits: achieving unlimited angular displacement, controlling numerous number of axes thanks to the certain combination of wheels motions, assigning force and position amplification individually, what helps to obtain both high speed and precision. In order to generate feedback force in the joystick, dedicated MR brakes were designed and built. The proposed feedback approach is an example of admittance control [1]. The joystick was built and tested at the Institute of Mechanical Technology of Poznan University of Technology. In the article, a theoretical model of the brake was shown together with analysis and discussion of its parameters. Additionally, it was supplemented with the results of theoretical and simulative studies. The paper also contains the outcome of the initial study focused on the analysis of the functionality, ergonomics and possibility of two-, three- and four axis control. It showed that the control algorithms played an essential role in motion control. They allow a rapid change of the generated resistance force during the change of motion direction. The obtained results validated the assumed design of the joystick with rotary elements and applied MR brakes due to the possibility of precisely control the motion resistance.