Application of microwave in wood tomography

Wood degradation and defects, such as voids and knots, affect the quality of lumber. The ability to detect the internal defects in the log can save mills time and processing costs. In this case, the microwave propagation is used to investigate the internal defect of wood. The principle of this case study is to measure the attenuation of microwave signal when propagates through the wood. The microwave trainer Type (e) 4510 that transmit 14.5 GHz with 20m W microwave signal is used and the measurements are made in voltage using multi-meter that connected with detector. The development of amplification circuit has been developed to amplifY the received signal from detector. Rubber wood is used as material under test, (rvlUT) with thickness used between 20mm to 60mm. The wood defection is created with known size and the wood is immersed in water in order to study the effect of moisture content on microwave signal. Several experiments must be performed with several samples of woods and results of measurement must be studied in order to determine the different measurement between the defect wood and good wood. Artificial Neural Network (ANN) is applied in Visual Basic to recognize the pattern voltage based on experiment data to develop 2D image and determine the internal characteristic of wood. All data presented are based on experiment results. The results from this work will determine the suitability to use microwave signal in wood scanning

Force Control for One Degree of Freedom Haptic Device using PID Controller

Haptics has been used as an additional feedback to increase human experience to the environment over years and its application has been widening into education, manufacturing and medical. The most developed haptic devices are for rehabilitation purpose. The rehabilitation process usually depends on the physiotherapist. But, it requires repetitive movements for long-term rehabilitation, thus haptic devices are needed. Most of the rehabilitation devices are included with haptic feedback to enhance therapy exercise during the rehabilitation process. However, the devices come with multiple degrees of freedom (DOF), complex design and costly. Rehabilitation for hand movement such as grasping, squeezing, holding and pinching usually does not need an expensive and complex device. Therefore, the goal of this study is to make an enhancement to One DOF Haptic Device for grasping rehabilitation exercise. It is improved to perform a force control mechanism with few types of conventional controller which are Proportional (P) controller, Proportional-Integral (PI) controller, Proportional-Derivative (PD) controller and Proportional-Integral-Derivative (PID) controller. The performance of the haptic device is tested with different conventional controller to obtain the best proposed controller based on the lowest value of Mean Square Error (MSE). The results show that PID Controller (MSE = 0.0028) is the most suitable for the haptic device with Proportional gain (Kp), Integral gain (Ki) and Derivative gain (Kd) are 1.3, 0.01 and 0.2 respectively. The force control mechanism can imitate the training motion of grasping movement for the patient

Application of microwave in wood tomography

Wood degradation and defects, such as voids and knots, affect the quality of lumber. The ability to detect the internal defects in the log can save mills time and processing costs. In this case, the microwave propagation is used to investigate the internal defect of wood. The principle of this case study is to measure the attenuation of microwave signal when propagates through the wood. The microwave trainer Type (e) 4510 that transmit 14.5 GHz with 20mW microwave signal is used and the measurements are made in voltage using multi-meter that connected with detector. The development of amplification circuit has been developed to amplify the received signal from detector. Rubber wood is used as material under test, (MUT) with thickness used between 20mm to 60mm. The wood defection is created with known size and the wood is immersed in water in order to study the effect of moisture content on microwave signal. Several experiments must be performed with several samples of woods and results of measurement must be studied in order to determine the different measurement between the defect wood and good wood. Artificial Neural Network (ANN) is applied in Visual Basic to recognize the pattern voltage based on experiment data to develop 2D image and determine the internal characteristic of wood. All data presented are based on experiment results. The results from this work will determine the suitability to use microwave signal in wood scanning