The power subsystem could possibly be the most underappreciated and forgotten of all of the on-board electrical subsystems. There may be several reasons for this, but the most likely is that most people just don't find the subject interesting enough. There are, of course, exceptions to this generalization, but it is safe to say that no one is currently planning a mission to demonstrate optimization of power system network. Grabbing the attention of spacecraft engineers are subjects like; more advanced communications systems, on-board data handling, and high speed data links, imaging systems, micro-propulsion, attitude control algorithms, sensors and actuators. It is natural that the best people in a small organization focus on the more exciting aspects of a mission; these subjects will typically be the differentiator of an organization's space mission from that of the rest of the world. However, it is also clear that these systems need power, and power that is delivered reliably and efficiently. For most companies and organizations planning their own microsatellite mission, the prospect of producing a reliable, yet affordable power system for their mission is not a trivial problem. Some non-traditional spacecraft manufacturers, such as Universities, are finding out the importance of a well-designed power system the hard way. The most common cause of failure on microsatellite mission to date has been the power system. As all microsatellite missions require some sort of optimization of power system network, and since this system will differ little from mission to mission, it makes sense to provide an off-the-shelf solution for common buses. By providing such a system, the responsibility of design of the power system within smaller organizations can be removed, allowing the mission design team to focus on the design of the rest of the spacecraft.

The main targets in designing control systems are stability, good disturbance rejection, and small tracking error. Several industrial robot manipulators are controlled by linear methodologies such as Proportional-Derivative (PD) controller, Proportional-Integral (PI) controller or Proportional-Integral-Derivative (PID) controllers. In this work, a Tunable Proportional Integral Derivative (TPID) controller is proposed for the control of a robotic arm. This tuning method is an attempt to obviate the shortcomings of the conventional PID controller where the proportional gain KP, integral gain KI and derivative gain KD, are fixed. The proposed controller provides opportunity for tuning the PID to be able to control the nonlinear movements and operations of a robot. The robot arm manipulator can be tuned as desired to provide control measures to enhance stability and suppress vibrations arising from robot arm operation. Simulation results showed an improvement over conventional PID controller for robotic arm manipulator.