Page 165 - Anatomy of a Robot

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150 CHAPTER FIVE
in a somewhat unplanned way. So get a jump on it and reserve spare resources the
robot can draw upon.
Once the basics of the robot have been roughed out, and the HLD has been written
down and reviewed, it’s time to get fully organized for development. No engineer likes
to wait for another engineer’s work to be completed, nor do they appreciate being stalled
for either decisions or resources. It’s important to put together working guidelines and
plans that make things work smoothly. Here’s one suggested way to help make this hap-
pen.
Divide the team up into independent groups. One group could handle the mechanics
and power systems. A second group could handle the automation. Have the teams sit
down at the beginning and work out all the interactions between the two groups. The
following issues should be addressed in this particular case:
What signals will the mechanics provide to the computer, and what signals will
the computer provide to the mechanics?
Sit down, draw out, and explain all the major movements and functions of the
robot in storyboard form. Not everyone will have read the specifications. Further,
many people cannot simply read specs and visualize the operations. Some people
have to see things and hear them before they will fully understand.
Discuss which tests will be performed and who will document the test regimens.
Discuss which Computer-Assisted Design (CAD) systems will be used for
mechanical and electrical design. Ideally, these systems should be integrated
so that it is easier to fit the printed circuit boards (PCBs) into the mechanical
chassis.
Discuss how the mechanics will fit inside the robot. Although a CAD system can
be used to align things, almost nothing can be a substitute for an audit of the crit-
ical areas in the robot. As an example, let’s suppose we are designing a PCB that
must fit within the robot. Let’s further assume that the CAD systems are not inte-
grated, as is often the case. Make a spreadsheet of every interaction point within
the robot where the PCB might interact with the mechanics and packaging. By
interact, we mean touch or require accommodation. For each of the interaction
points, enter all the relevant dimensions for that point into the spreadsheet, includ-
ing XYZ coordinates. With a thorough tabulation of the interaction points, it is
much easier to determine if the PCB will fit within the robot’s mechanics without
an error. Without such attention to detail, it is very easy to suddenly realize that a
post is right where we thought the PCB would go. Make mockups, if need be, out
of Styrofoam and cardboard. Just don’t let the “customer” see it!