Energy optimal point-to-point motion profile optimization

Abstract

Position-controlled systems driving repetitive tasks are of significant importance in industrial machinery. The electric actuators used in these systems are responsible for a large part of the global energy consumption, indicating that major savings can be made in this field. In this context, motion profile optimization is a very cost-effective solution as it allows for more energy-efficient machines without additional hardware investments or adaptions. In particular, mono-actuated mechanisms with position-dependent system properties have received considerable attention in literature. However, the current state-of-the-art methods often use unbounded design parameters to describe the motion profile. This both increases the computational complexity and hampers the search for a global optimum. In this paper, Chebyshev polynomials are used to describe the motion profile. Moreover, the exact bounds on the Chebyshev design parameters are derived. This both seriously reduces the computational complexity and limits the design space, allowing the application of a global optimizer such as the genetic algorithm. Experiments validate the added value of the chosen approach. In this study, it is found that the energy consumption can be reduced by 62.9% compared to a standard reference motion profile.

An Industrial Applicable Approach towards Design Optimization of a Reciprocating Mechanism: an emergency ventilator case study

“…However, in this paper we avoid such approximations leading to inaccuracies by exactly modelling the mechanism in CAD software. As literature proves [21], the models of machines built by machine designers are very accurate. In that way, using these CAD simulations in an optimization algorithm give trustworthy results.…”

CAD-Based Design Optimization of Four-Bar Mechanisms: An Emergency Ventilator Case Study

“…// Prepare to deal with the remaining 2 dimensions. Choose any 2 of the values of Equation (16). Here, the first 2 are chosen.…”

“…However, as noted by [5], the analytical computation of mechanism dynamics can become complex when dealing with systems containing a large number of components, as is commonly the case in industrial machinery. Alternative approaches, such as the use of generic equations of motion, have been proposed in the literature [16]. However, these methods still typically require information such as the reduced motor inertia as a function of motor position, which can be obtained by the method of kinetic energy [17], being cumbersome and error-prone.…”

Real-Time Embedded System-Based Approach for Sensing Power Consumption on Motion Profiles

“…Another aspect to consider besides the motion profiles is the control algorithm, which is designed to keep the tracking error as low as possible, guaranteeing efficiency in the execution of the movement [15]. The most commonly used control technique is the classical Proportional-Integral-Derivative (PID) and PD controllers as observed in [16].…”

“…For their part, Wang et al propose a methodology for using degree 4 polynomials in an industrial robot [25]. On the other hand, the reduction of energy consumption has been analyzed in point-to-point movements using trapezoidal and cycloid profiles [2], as well as trajectories based on Chebyshev polynomials [15]. A review and classification of energy-saving optimization strategies for robotic and automatic systems are presented in [26], being a software approach based on motion planning, an effective and economical technique easy to implement on existing systems [27].…”