During the early stages of the Industry 4.0 era, teleoperation with human involvement in manufacturing processes and robot operation remained important. The existing teleoperation technologies have limitations in providing operators with spatial awareness and initiative control mechanisms, making their applications difficult in tasks with high complexity and precision. This study implements the advancements from the internet of things (IoT) and virtual reality (VR) technology to improve the real-time teleoperation for industrial robots. The proposed design utilizes the benefits of the Message Queuing Telemetry Transport (MQTT) protocol in conjunction with a cloud broker, which has not been addressed significantly in previous studies for teleoperation. This setup enables the system to efficiently handle substantial amounts of data in short periods of time, allowing for an uninterrupted user experience while maintaining a consistent connection regardless of distance. Real-time robot control is accomplished by tracking the user’s hand movements with a VR controller while providing the user with visual feedback from the VR environment. The incorporation of VR technology intends to improve the intuitiveness of controlling robot operations, provide more responsive feedback, and improve the quality of work performed by operators. Practical experiments are conducted with an industrial robot to observe the performance against the system under different internet conditions and different QoS setups. The evaluation criteria primarily concern about latency and accuracy. The experiment aims to evaluate the effectiveness and scalability of the suggested system and to offer significant insight into its advantages and limitations relative to existing control system through systematic investigation.

Robotic manipulators play an innovative role as a new method for high-precision, large-scale manufacturing of composite components. However, machining composite materials with these systems presents unique challenges. Unlike traditional monolithic materials, composites exhibit complex behaviour and inconsistent results during machining. Additionally, robotic manipulator as a machine tool often associates with stiffness and vibration issues which adds another layer of complexity to this approach. By employing a comprehensive analysis and a combination of quantitative and qualitative review methodology, this review paper aims to survey diverse properties of composite materials by different categories and their interaction with machining processes. Subsequently, a survey of manufacturing techniques for composite machining following with a review in various modeling practices to capture material machining behaviour under a systematic framework is presented. Thereafter, the reviewed literature examines the errors inherent in robotic systems, alongside ongoing research efforts in modeling to characterise robot behaviour and enhance its performance. Afterward, the paper explores the application of data-driven modelling methods, with a primary focus on digital twins, in enabling real-time monitoring and process optimisation. Finally, this paper aims to identify the gap in this field and suggests the potential routes for future research and application as well as their challenges.

Electrical discharge drilling of blind holes has been a challenging task due to the inherent difficulties in removing debris from the discharging gap. This paper investigates the working mechanism and effects of new stepped electrodes which are used in conjunction with injection flushing in drilling deep blind holes. A series of theoretical simulations and comparative experiments were conducted using cylindrical electrodes and two types of stepped electrodes. Pulse waveforms were captured to analyse the discharge status. Surface topography and machining quality were analysed using scanning electron microscope (SEM) images. The machining performance was evaluated by studying the material removal rate (MRR) and tool wear ratio (TWR). Experiment results show that internal flushing caused the debris to circulate in the machining zone and led to abnormal discharges, disrupting the formation of the plasma channel. The MRR was increased by 75% and 82% when using cylindrical electrodes with pressures of 120 psi and 40 psi, respectively. In contrast, the MRR with injection flushing was about 80% of that without injection flushing when using stepped electrodes. Regardless of the type of electrode, the application of injection flushing resulted in the increase in the maximum effective machining depth.