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The purpose of this study is to design and manufacture a new remote center of motion (RCM) mechanism for use in laparoscopic surgical operations. In addition, obtaining the forward and inverse kinematic equations of the RCM mechanism and performing real-time position control with the Proportional–Integral–Derivative (PID) control method.

At the design stage, it is benefited from similar triangle rule. To obtain the kinematic equations in a simple way and facilitate control, two-fold displacement ratio is provided between the limbs where linear motion occurs. The rotation and displacement amounts required to move at the RCM point have been calculated by using the kinematic equations of the mechanism. Limb dimensions and motion limits are determined in the manner to avoid singularities and collisions. The x, y and z coordinates of the end effector have been defined as the reference point. Control of the mechanism was provided by PID control. To generate the user interface and control algorithm, MATLAB/Simulink real-time toolbox has been used. Four reference points were determined, control was performed and position error values were examined. MF634 Humusoft data acquisition card has been preferred to collect data from encoders.

A novel RCM mechanism has been designed and manufactured. Kinematic equations of this mechanism have been obtained. Position control of the cannula tip has been performed using PID control method for four different reference points. After settlement, maximum position error has been observed as 0.45 mm.

Structure of the designed mechanism is quite simple. Thus, costs are quite low. The operation area of the operator is widened by hanging the mechanism from the ceiling, so operational capability of health personnel is increasing. It helps to decrease the operation time and increase the success of the operation.

With this study, it is aimed to contribute to the literature by designing a new RCM mechanism. The rotation of the mechanism around the RCM point is provided by only one rotary motor, and the displacement of the RCM point in the vertical axis is provided by only one linear motor. The mechanism is also a surgical robot. The designed system is suitable for use in robot-assisted laparoscopic surgery in terms of maneuverability.

The purpose of the study is to design a three-dimensional (3D) triglide parallel robot with a different approach and to control the manufactured robot via sliding mode control method that has not been applied to the robot before.

The x, y and z coordinates of the end effector of the robot have been given as a reference. The x, y and z reference values are transformed as new reference values of the vertical movement of the robot on the endless screw by using the inverse kinematic equations of the robot. The control of the robot over these reference values is provided by a sliding mode control. The MATLAB/real-time toolbox has been used for creating the interface. The real-time control of the triglide robot has been carried out with a sliding mode controller in the Simulink environment.

When the results of the sliding mode control are examined, it is seen that the desired reference values are provided in about 0.6 s. The velocity of the sliding limbs in each arm of the robot is approximately 50 mm/s. The reference values have been reached using the sliding mode control method, with an average error of 0.01 mm. In addition, the problem of chattering in the system caused by using the sign function has been relatively eliminated by using the saturation function instead of the sign function. Thus, the sliding mode control method with saturation function is more feasible.

In this study, the triglide parallel robot was manufactured using a 3D model after taking into consideration the dimensions of the 3D model. After production, the necessary hardware connections were provided, and a real-time sliding mode control method was implemented to the robot by using the interface program in MATLAB/Simulink environment. The literature contribution of the paper is the real-time control of the triglide robot with the sliding mode control method.

The trust in participation banks depends largely on authentic dependence on Sharia, legal financial instruments and fair yet transparent distribution among account owners and banks. Taking into account the economic Islamic principles and those of mudarabah agreement, this study aims to identify problematic areas pertaining to profit sharing in addition to revealing opportunities leading to the improvement of the profit distribution system while developing a new profit distribution system proposal.

This study proposes two hypotheses (H). H1: There are partial deviations between the profit considered to be legal according to the economic principles of Islam and the practice of participation banking. H2: There are partial deviations or loss of right in practice between the mudarabah contract concluded among owners of participation account and participation banks. In-depth interview technique and review of the literature including legislation were used to determine the parameters affecting the distributed profit. The collected data was tested through comparison with the theoretical framework of the mudarabah contract.

There are two separate fund pools used in participation banks, including equity and participation accounts. Managers’ selection of pools set according to their personal goals related to balance sheet profit management may cause profit to pass between participation accounts and equity. Many issues negatively affect the distributed profits. For example, incomes from funding commissions, reserve requirements and idle funds, although they originate from participation accounts, are recorded in the bank’s income. In addition, the bank does not return the profit initially recorded in its own account to participation pools, whether or not profit.

The interviewed officials were cautious to avoid a negative perception of the sector. This made it difficult to determine the real situation of applications decided with initiative in profit distribution. Although the authorization documents have partially been published, it is still difficult to access most licensed documents. There is no independent audit report made considering the interest-free banking principles regarding the profit distribution system of participation banking. The scarcity of the literature on the subject is another limitation. The research does not cause any harm to the reputation of participation banks.

Adopting a single-pool system in line with the global practices will end the shift of right between pools while ensuring a fair and transparent system. In this system, the bank equities, other shareholders’ funds and participation accounts are collected and operated in a single pool. The pool profit and loss are distributed as per the shares in the pool. The profit per each participation account is distributed based on the share of each participation account in the pool and profit-sharing ratio.

Participation banking is expected to support the real economy by means of production, leasing, merchandising based on certain religious, ethical and contractual principles. Bringing funds of conservatives, that does not go to conventional banks for avoiding of interest, in the economy is expected to provide new sources to reduce the foreign dependency for the economy and to supply a financial alternative for the conservatives who stay away from interest-based economic activities. However, if this will represent an alternative to debt-based systems, then products, contracts, business processes and legislations driven according to interest-free banking principles should be developed.

This study introduces and analyzes a new proposal of the profit distribution system of participation banking. A similar methodology is used in interest-free banking on a global scale, especially in Malaysia, and is compatible with the profit distribution decisions in AAOIFI’s depositor accounts. However, this methodology is considered to be new as far as participation banking is concerned. The implementation of this new methodology will eliminate several problems identified in the profit distribution system of participation banks. This research provides an academic contribution to the participation banking profit distribution system and represents a reference material on the subject.