Robotics and FPGAs (8) - Design of a Multi-Channel Servo Controller PCB (Rev. 1), Part 2 - Analysis and Component Selection

This blog post describes the analysis and component selection stage of the multi-channel servo controller board design and it is during this stage where, sadly, for most of us it all begins to go wrong.  It is during this process that every datasheet must be read and reread again and again, until every line of text and every curve in a graph is thoroughly understood. It is at this stage that some, out of despair of a looming deadline, decide to fall on their knees, look skywards and utter words of reverence, utter words of importance or just words.  

It is at this stage that others decide it  is time to put on their jeans and T-shirt and lock themselves in their study. Only to emerge  a few days later wearing a robe and sandals. As you will find out in this blog post we chose to put in a few night shifts to resolve the recurring problems in the design and felt justified emerging with our guru's attire. However, we have known some at this stage of the design process to decide that X marks the spot and continuously aim their heads at it, ceremoniously. Entertaining as this method could be, we prefer ours. However, we recommend you should choose the problem solving method that works for you!

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First Impression (5) - The MG996R Servo, An Insider's View

To me all similarly priced servo motors look the same and promise the same performance and maybe they ought to, too. So amongst all the servos out there how do you choose that perfect one for your application? Well, I suppose that is the question that needs answering! Quite fortunately when I had to answer that question, of which set of motors to choose for the 17 Degree-of-Freedom (DOF) robot project, the Tower Pro MG996R motors came recommended, as part of the 17 DOF robot kit. Hence, these motors were thrust upon me.  

The predecessor to this motor, the MG996, did not receive the most glowing of reviews and was particularly noted for its lack of accuracy and centering. However this version is meant to be a worthy successor with a redesigned PCB and Integrated Circuit (IC) control system, which makes it more accurate. We provide an insider's view of this servo in this blog post.

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