Design of Prototype Load Moment Indicator on Mobile Crane using Microcontroller based on Lifting Load Chart

Abstract

A load moment indicator (LMI) is an electronic device on heavy equipment cranes that can provide information and a warning system to operators in the event of an overload during the lifting load process. This tool has a very important role because it provides accessible information to the operator about the safe working load (SWL) that the crane can lift. Mobile cranes have a high accident potential when compared to tower cranes, and this is because mobile cranes have high mobility. In this paper, a prototype LMI has been made on a mobile crane based on a microcontroller that can provide value. The method used is an algorithm to find the closest value from the lifting load chart of a crane car. The programming algorithm is still manual, namely by equating and comparing boom crane conditions such as boom length, boom angle, and radius contained in the lifting load chart with the results of measuring boom crane conditions by sensors. The nearest value search algorithm follows the rules of how to read the mobile crane lifting load chart. The test results show that the sensors used to measure boom length, boom angle, and actual load each have a maximum relative error of 0.92%, 8%, and 4%, respectively. Meanwhile, to find the SWL value, the comparison scanning method can provide the SWL value according to the lifting load chart of the mobile crane. It can provide accurate information on whether the lifting load process is safe or overloaded.