This research aims to develop a pickup truck to become a hi-rail vehicle that runs on meter gauge railways in Thailand. It is intended to be used for rails maintenance or response times during train derailments and for accessing inaccessible areas via rails in emergency situations. A hi-rail vehicle can travel both on rails and roads. The guide train steel wheels set is designed to have steel wheels running on rails with the vehicle being raised above the rails using a programmable logic controller for hydraulic cylinders. The results of the road test can run at a normal speed of not more than 90 kilometers per hour. The results of the test run on the rails can run at speed of not more than 30 kilometers per hour. There is a vibration of the hi-rail vehicle due to the designed guide train steel wheels set mechanism that can be accepted.

The paper presents an experimental study that aims to measure the compressor electric current of a split-type air conditioner for analyzing the various abnormal condition of the R-32 refrigerant pressure, especially for detecting compressor electric current while occurring dirt in the evaporator coil and condenser coil. The method was to install sensor devices to measure the temperature and humidity of inlet air and outlet air, and the velocity of the air outlet of the evaporator unit. In condenser unit was to measure the electric current compressor and electric power input. All data from sensors send to the Arduino board and using Parallax Data Acquisition (PLX-DAQ) Excel Macro for the record. The results show physical behavior and the changing of compressor electric current according to the abnormal condition of the refrigerant system, blocking of condenser and evaporator coil.

This research was to propose the DC linear actuators and a stepper motor as mechanical drive systems such as brake pedal, clutch pedal, forward-reverse gearshift, gear position selection, tail-lifting system to lift the chemical tank, and the speed selection system of power take-off (PTO). The DC linear actuators were used instead of the muscles, arms, and legs of the human being. The stepper motor was used to control the steering direction of a driverless tractor robot. The control was based on the programmable logic controller and radio remote control for the driverless tractor robots. Both MATLAB/Simulink simulation and experimental results were the validation and satisfactorily achieved. The test results of the driverless tractor robot in spraying water on a football field were satisfactory steering response and rapid braking.

The research proposed the design and installation of the DC motor with a feedback position used to control the steering direction of a rice-planting machine here will be converted into driverless robots. The MATLAB/Simulink software is used to simulate and measure signal drive from the servo controller board to obtain results that can be used to drive BTS 7960 motor driver module for the DC motor with feedback position. The SkyDroid T10 is used to remote control of steering direction of rice-planting machines and the mechanism to drive all robots. The results of test results of the robot spraying chemicals in rice fields were excellent. The operator can remotely control the robot through the camera from the mobile phone. The chemicals can be sprayed quickly, and the chemicals are distributed evenly and evenly into the ground.