A solar tracker is a device that orients a payloads can be toward the sun. Trackers are used to minimize the angle of incidence between the incoming sunlight and photovoltaic panel. This increases the amount of energy produced from a fixed amount of installed power generating capacity. In standard photovoltaic applications, it is estimated that trackers are used in at least 85% of commercial installations greater than 1MW from 2009 to 2012. This study is concerned about the structure design of a low coast and entry level dual axis solar tracker. This research purpose is to propose and verify a method to achieve higher product quality, lower costs, and far less physical testing. As a result of the new mechanism development, the volume of moving parts and the weight of main parts decreased by 46.8% and 20% respectively
This study is concerned about the optimal design of the main frame in a moper. Mopper is widely used for cleaning in the fields such as airport, subway, train station, large shopping mall, department store, hospital, government buildings, school, industrial building floor, etc. Especially, main frame in mopper are stressed by high, mostly loads. Nevertheless, design of main frame is dependent on experience, and it will cause reliability reduction and cost increase. This research purpose is to propose and verify a method to achieve higher product quality, lower costs, and far less physical testing. In this study, design parameters used for optimization are each thickness of 4 square pipes and 1 plate in the main frame. The result after optimization showed that the weight of main frame reduced to maximum 6.5% when compared with the initial design in main frame.
The object of this study is concerned about the optimal design of the supporting frame in a twist screen. Twist screen is widely used for grading and screening materials in the fields such as coal-selecting, mining-selecting, building materials, electrical power and chemical industry, etc. It is composed of base, supporting frame, vibrator, screen, spring, trough, clamp and etc. Especially, supporting frame in twist screen are stressed by high load, mostly it is shock-type loads. Nevertheless, design of base is dependent on experience, and it will cause reliability reduction and cost increase. The supporting plate is composed by the upper plate, the bracket and etc. This research purpose is to propose and verify a method to achieve higher product quality, lower costs, and far less physical testing. In this study, design parameters used for optimization are the upper plate thickness(8㎜, 10㎜, 12㎜) and the bracket thickness(8㎜, 10㎜, 12㎜) in the supporting frame. The result showed that base weight reduced to maximum 25.8% when compared with the current twist screen.
This study is concerned about the optimal design of the base in a vibrating screen. Vibrating screen is widely used for grading and screening materials in the fields such as coal-selecting, mining-selecting, building materials, electrical power and chemical industry, etc. It is composed of base, frame, vibrator, screen, spring, trough, clamp and etc. Especially, base in vibrating screen are stressed by high, mostly shock-type loads. Nevertheless, design of base is dependent on experience, and it will cause reliability reduction and cost increase. The base is composed by the lower plate, the middle plate and the upper plate. This research purpose is to propose and verify a method to achieve higher product quality, lower costs, and far less physical testing. In this study, design parameters used for optimization are the lower plate thickness(7mm, 9mm, 11mm), the middle plate thickness(4mm, 4.5mm, 5mm) and the upper plate thickness(7mm, 9mm, 11mm) in the base. The result showed that base weight reduced to maximum 19.1% when compared with the current vibrating screen.
This study proposes the compensation method for the mechanical deflection error of a SCARA robot. While most studies on the related subject have dealt with the development of a control algorithm for improvement of robot accuracy, this study presents the control method reflecting the mechanical deflection error which is predicted in advance. The deflection at the end of the gripper of SCARA robot is caused by the self-weights and payloads of Arm 1, Arm 2 and quill. If the deflection is constant even though robot’ posture and payload vary, there may not be a big problem on robot accuracy because repetitive accuracy, that is relative accuracy, is more important than absolute accuracy in robot. The deflection in the end of the gripper varies as robot’ posture and payload change. That’ why the moments , and working on every joint of a robot vary with robot’ posture and payload size. This study suggests the compensation method which predicts the deflection in advance with the variations in robot’ posture and payload using neural network. To do this, I chose the posture of robot and the payloads at random, found the deflections by the FEM analysis, and then on the basis of this data, made compensation possible by predicting deflections in advance successively with the variations in robot’ posture and payload through neural network learning.
Robots in various types carry and assemble parts through repeatedly and accurately moving to stored locations by combining linear motions. And, linear systems are used in orthogonal axes of robots and driven via ball screws, such as 2-axis cartesian coordinate robot in this paper. This paper presents the effect of the linear motion guide that is used in 2nd axis in 2-axis cartesian coordinate robot. Some simulation results show that the linear motion guide influence greatly in robot performance such as the nominal life of linear guide. When use LM guide that have capacity near in 2nd axis, this paper show that the nominal life on LM block of 1st axis increases 37.4% and that the specification of 2nd axis LM guide influences greatly the nominal life of 1st axis LM block.
This paper presents the design for performance improvement of 2-axis cartesian coordinate robot. We cannot obtain the expected design performance unless we select the best-fit linear system for the robot. For this, this paper finds conditions of most suitable to select a LM(Linear Motion) guide and design a 2nd axis arm. By simulation results, the 2nd axis LM guide and the 2nd axis arm structure are confirmed that influence to the deflection of work piece end and the loads on 1 axis LM block. On using LM guide that have capacity near, this paper shows that the maximum load on LM block of 1 axis increases 4.23% and the maximum deflection of work piece end increases 7.95%.
This study is concerned about the robot joint mechanism with the slider joint. Most of robots are sliding using rolling bearing, cam follower or roller follower in the slider joint. Because such structure must impose pre-load so that outer ring of the bearing may have suitable contact force on contact side, when used many long term, life is fallen, and become factor of rising prices because must do precise machining about parts that use. This research proposes method to solve such problem. This research applies method to use sliding bearing instead of rolling bearing and develope mechanism that can operate for this. Also, this research develops structure that can transmit power using gear to reduce cost price. And optimal design for gear and main parts is achieved.