During this period, we had focus on the hardware of the project that is the Development of miniature robot with Servo-powered legs. The hardware that are in focus during this period are the servo motor, check degree of freedom (DOF), and prototype of robot. During the research, Servos contain a small DC motor, a gearbox and some control circuitry, and feed on 5 volts at about 100mA maximum, and about 10-20mA when idle. They have a three-wire connector, one common wire (0 volt, usually black), one +5v wire (usually red), and one signal wire. In normal use they are controlled by pulses of about 1 to 2 milli-seconds at a repetition rate of about 50 per second. A short pulse makes the servo drive to one end of the travel, a long pulse makes it drive to the other end, and a medium one puts it somewhere proportionally between. Some servos have gear components that allow them to rotate continuously. Using a Radio Controlled (RC) servo for steering is a good method, because the position of the steering mechanism is determined by the length of the servo drive pulse, which can be generated by a software countdown loop or a hard-ware counter. If an RC servo is used as a drive motor, wheel motion sensors are needed on at least one wheel as in any DC motor system. The use of an RC servo for driving only simplifies the mechanics. In summary, servos are very small and precise motors. Degrees of freedom is a general term used to express dependence on parameters, and implies the possibility of counting the number of those parameters. In mathematical terms, the degrees of freedom are the dimensions of a phase space. Robot arms are often categorized by their degrees of freedom (typically achieving more than six degrees of freedom). This number typically refers to the number of single-axis rotational joints in the arm, where a higher number indicates an increased flexibility in positioning a tool. This is a practical metric, in contrast to the abstract definition of degrees of freedom which measures the aggregate positioning capability of a system.
Problem Faced
The selection of the hardware seems to take more that the proposed timeline. This is due to other assignments need to be carried out other than to focused on the project.
Solution
The problems is handle by speeding up the research pace for such using the common manufactured component available in the market that meet the specific requirement of this project. Cytron Technologies for example offer many sets of component with detail explanation on what can we can expect by their supplied components such as the users manual and the data sheet. They also make a couple of suggestion on what combination that those component fits in.
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