Pick-and-placement control method and system for fragile materials

Abstract

The invention discloses a pick-and-placement control method and system for fragile materials, which is particularly suitable for a gas diffusion layer of a proton exchange membrane fuel cell. The method comprises the following steps of: executing a pick-and-placement operation on the materials through a tail-end pick-and-placement mechanism of a mechanical arm with multiple degrees of freedom, and detecting contact force by a force sensor at the same time; performing regulation and an analogue to digital (A / D) treatment on a detected force signal which then serve as a feedback signal, and establishing closed loop control with an expectation force value serving as a control signal, thus acquiring a force deviation signal; establishing closed loop control with an actual position signal for driving a servo motor of the tail-end pick-and-placement mechanism serving as a feedback signal, and an expectation motor position value serving as a control signal to build, thus acquiring a position deviation signal; and overlapping the deviation signals to acquire a comprehensive position deviation signal, and driving the servo motor correspondingly by a servo amplifier. According to the pick-and-placement control method and system, the pick-and-placement contact force can be accurately controlled, and the materials can be prevented from being damaged due to overlarge contact force, so that the fragile materials can be reliably picked and placed.

Description

technical field [0001] The invention belongs to the field of material transportation, and more specifically relates to a pick-and-place control method and system for brittle materials, especially gas diffusion layers of proton exchange membrane fuel cells. Background technique [0002] The membrane electrode assembly of a proton exchange membrane fuel cell (PEMFC, Proton Exchange Membrane Fuel Cell) is mainly composed of a proton exchange membrane, a catalyst and a gas diffusion layer (GDL, Gas Diffusion Layer). It is the core component of a proton exchange membrane fuel cell, equivalent to The CPU in the computer determines the performance of the fuel cell. GDL is a loose and brittle carbon fiber material with low mechanical strength and is easily broken. When the pick-and-place mechanism contacts brittle materials like GDL at a high speed, it is easy to generate excessive contact impact force and cause damage to the material, so the contact force must be strictly controll...

AI Technical Summary

Problems solved by technology

[0003] At present, there are pick-and-place devices that use springs to control the pressure in the pick-up process. For example, the patent application with publication number CN1533237A discloses a block-type placement head of a placement machine, in which springs are used to control the pressure. Simple, but the pressure adjustment is rough and the accuracy is not enough. For the pick-and-place of brittle materials, it is easy to fail to pick up or damage the brittle materials

In some other schemes (such as CN101707181A, CN102157351A), it is proposed to control the contact force by speed switching during the pick-and-place process, but these methods are generally suitable for pick-and-place operations on materials with high strength (such as chip pick-and-place). It is not suitable for picking and placing brittle materials, because the picking and placing of brittle materials requires higher contact force

At the same time, the picking of brittle materials such as GDL in the existing preparation process is mainly done by hand, which has low efficiency, high cost, and unguaranteed product consistency, which greatly limits the commercial application of the product

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