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This paper aims to deal with the force and position tracking problem when a robot performs a task in interaction with an unknown environment and presents a hybrid control strategy based on variable admittance control and fixed-time control.

A hybrid control strategy based on variable admittance control and fixed-time control is presented. Firstly, a variable stiffness admittance model control based on proportional integral and differential (PID) is adopted to maintain the expected force value during the task execution. Secondly, a fixed-time controller based on radial basis function neural network (RBFNN) is introduced to handle the model uncertainties and ensure the fast position tracking convergence of the robot system, while the singularity problem is also avoided by designing the virtual control variable with piecewise function.

Simulation studies conducted on the robot manipulator with two degrees of freedom have verified the superior performance of the proposed control strategy comparing with other methods.

A hybrid control scheme for robot–environment interaction is presented, in which the variable stiffness admittance method is adopted to adjust the interaction force to the desired value, and the RBFNN-based fixed-time position controller without singularity problem is designed to ensure the fast convergence of the robot system with model uncertainty.

The purpose of this study is to raise the issue of contemporary retromania with marketing historians.

This is a reflective essay combining personal experiences with empirical exemplars.

It is found that retromarketing is a subject requiring scholarly scrutiny. The commodification of the past is increasingly prevalent and marketing historians are ideally placed to lead the discussion.

As yestermania is unlikely to evaporate anytime soon, it provides rich, socially and managerially relevant pickings for marketing historians.

Aside from the scurrilous suggestion that historians should get out of the dusty archives, it argues that originality is overrated.