A review of predictive monitoring approaches and algorithms for material handling systems

Abstract

Material handling systems (MHS) include a wide range of systems and equipment that are used for handling, movement, storage and control of materials during manufacturing. MHS can represent a significant portion of the cost to make a product and there can be significant cost savings in manufacturing processes if unexpected failures of such systems can be avoided and maintenance costs lowered. This paper first surveys the common maintenance practices of MHS including three typical warehouse MHS e.g. automatic picking system (APS), goods to destination (GDS), and Erector. The survey from end users shows that the majority of the companies does not keep the record of their past failures or improve their maintenance practices after major failures occur. Even the end users with more advanced maintenance programs use more reactive maintenance approaches, as opposed to preventive maintenance approaches which have the potential to lower the chances of unexpected failures and costly repairs. The present paper also reviews the past works in predictive monitoring of MHS categorized as machine level, component level, and production level. Although there has not been a large body of research published around this topic, the existing works demonstrate the suitability of applying Prognostics and Health Management techniques for improving the reliability of such machines and reducing their downtime. The opportunity for MHS to move towards a condition-based maintenance approach is still a few years away, and many end-users of this equipment would have to first adopt a good preventive and reliably centered maintenance philosophy. Once that occurs, the OEM's would be the most likely candidates for further developing and implementing the research work and methods for MHS predictive monitoring.

Analysis of maintenance outsourcing challenges for belt conveyors in the Industry 4.0 era

“…In the era of I4.0, many organizations operating MHE opt for maintenance outsourcing. According to a survey on the maintenance processes of MHE, including belt conveyors by Siegel et al (2014), 45% of organizations responded that their future maintenance strategy needs modification and 17% of them were unfamiliar with the various maintenance techniques. Furthermore, a large majority of respondents (74%) prefer that OEM perform the maintenance.…”

“…mobile sensors and fixed sensors may have to be used for condition monitoring of belt conveyors (Liu et al, 2014). Siegel et al (2014) pointed out that most approaches for monitoring conveyor belts include embedding conductive arrays, cords or layers in the belt and monitoring the belt by feeding electrical and magnetic fields. As the conductive material collapses the fields, a detector can be used to determine the continuity of the conductive arrays (or layer) and detect potential belt damage before it is extended.…”

“…Many maintenance data are incorrect, incomplete, unstructured, contain missing values and lack annotations (Kumar and Galar, 2018). A survey conducted by Siegel et al (2014) among different material handling equipment operators revealed that even after severe failures, many organizations do not keep track of their previous failures or improve their maintenance methods. According to the survey responses, only 14% of organizations use an information system to maintain maintenance history records, whereas 57% do not keep any records at all.…”

“…In addition to the belt, a conveyor system’s drive unit is an essential system that includes components, such as the motor, bearing, gearbox, brake system, etc. (Siegel et al , 2014). Drive unit components can be monitored with a variety of sensors such as vibration strain gauge, motor current (Kruse, 2005; Hills, 2009), etc.…”

“…To keep a conveyor belt safe and reliable throughout its lifespan, it must be maintained (Liu et al, 2014). However, a survey by Siegel et al (2014) among various material handling equipment (MHE) operators revealed that even after suffering productivity losses as a result of downtime or failure of MHE, the vast majority of organizations, to the tune of 61%, did not alter their maintenance strategies or plans. Herein lies the significance of diligent plans for the maintenance of MHE in general and belt conveyors in particular.…”