Abdur Rosyid's Blog
Just a few notes on mechanical engineering and robotics
Telecommunications and computer/device network communications can be broadly divided into three types: simplex, half duplex, and full duplex. The simplex communication means one-way communication. It’s like a one-way road. The communication can only be performed in one direction all the time. For example, communication between mouse and keyboard to computer (the mouse and keyboard always …
The communication can be broadly divided into serial and parallel communications. In the basic scheme of serial communication, only one wire, in addition to the ground wire, is used to transmit the bits from the sender to the receiver. Every bit is transmitted one by one in a sequential manner. There are two types of …
Three common protocols used in automation are serial fieldbus-based, Ethernet-based, and wireless. To perform better than the standard serial fieldbus and Ethernet communication protocols, some companies have developed some custom protocols for industrial automation purpose. Historically, industrial automation widely used serial fieldbus-based communication protocols in its earlier times. Although these serial fieldbus-based protocols have been …
The communication protocols are standardized by ISO in a scheme called the Open Systems Interconnection (OSI) model. The OSI model structures the communication protocols into seven layers as shown in the following table. In other words, there are various communication protocols which can be at any of the seven layers. For example, Ethernet is a …
PLC vs DCS Programmable logic controller (PLC) is widely used in industry. It is typically used in a small-scale system to control multiple devices in a centralized manner, i.e. one PLC controls multiple components. Distributed Control System (DCS), as implied by the name, implements a decentralized control architecture such that a failure in one sub-system …
Programmable Logic Controller (PLC) is a famous control unit and widely used in industry. It has been initially used for discrete control, i.e. ON and OFF control. The domain of use is wide, from a simple flip-flop light to flow or process control. It was made at the first place to replace relay- and timer-based …
Sebelum kita membahas tentang motor servo (servo motor), kita perlu berbicara tentang sistem servo (servo system). Sistem servo adalah sistem kontrol yang menggunakan sistem umpan balik negatif (negative feedback system), dalam rangka untuk memberikan kompensasi pada sistem yang dikontrol agar menghasilkan output sesuai dengan yang kita inginkan. Meskipun sistem dengan umpan balik kecepatan saja sudah …
Motor stepper bekerja berdasarkan dua sinyal input: STEP dan DIR. Sinyal STEP menyatakan jumlah step yang harus ditempuh ketika berputar. Besaran sudut untuk setiap step tergantung pada spesifikasi motor (yakni jumlah step per satu putaran motor). Adapun sinyal DIR menyatakan arah putaran motor. Motor stepper umumnya memiliki empat buah kabel, yang biasa disebut sebagai A+, …
Brushless DC motor (BLDC motor) biasanya memerlukan tiga sinyal analog (voltase analog) untuk membuatnya berputar, yaitu U, V, dan W. Ketiga sinyal (voltase) kontrol ini mesti disuplai oleh sebuah drive. Motor BLDC bekerja berdasarkan komutasi elektronik. Ini biasanya dilakukan dengan menggunakan “hall sensors” atau “encoder” yang berputar bersama dengan motor. Hall sensors lebih lazim digunakan …
Pada artikel ini, saya akan menjelaskan bagaimana mengontrol posisi (sudut) brushed DC motor. Untuk melakukan hal ini, kita perlu menerapkan “closed-loop control”. Ini bisa kita lakukan dengan menggunakan encoder. “Low-cost brushed DC motor” cukup banyak yang dijual dengan dilengkapi magnetic encoder yang menjadi satu paket dengan motor. Bisa juga memakai optical encoder yang memberikan presisi …