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Vorpal The Hexapod User Guide

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Revision as of 02:57, 3 July 2017 by Vorpalwiki (talk | contribs) (Proper Care of the Servo Motors)

Changing the Battery

To choose batteries properly, see Vorpal Combat Hexapod Battery Recommendations.

Here are the steps to change the battery:

  • Turn the Hexapod off using the power switch.
  • Twist the cap counter clockwise (when looking from above) until it comes off.
  • There are red JST connectors tying the battery to the Hexapod's electrical system. Grip the plastic connectors (not the wires!) one side in each hand. Pull apart. Sometimes wiggling them helps get them loose more easily. Never pull via the wires or you may pull the connectors apart internally.
  • Connect a new battery pack (or after recharging the pack you removed) in the same way. Make sure the JST connectors are lined up properly.
  • Place the tabs on the edges of the cap into the matching indentations in the top, push down slightly and turn clockwise.

Turning the Hexapod On and Off

To turn the robot on:

  • Turn the dial all the way counter-clockwise, it should be pointing to STP (stop).
  • Press the on/off switch upward (toward the "1" label).
  • Select the mode you want using the dial.

To turn the robot off:

  • Press the on/off switch downward (toward the "0" label).

Using the Dial to Select Mode

Proper Care of the Servo Motors

Your Vorpal Combat Hexapod is equipped with metal-gear servos that should last a long time under proper care. But they can be damaged if misused.

There are two main ways servos fail: overheating and too much weight pressing down on them. Overheating causes the insulation in the motor coils to burn up, causing the motor to short circuit. Weight stress on the servo can cause one or more gear teeth to break.

Overheating is caused either by:

  • continuously moving the hexapod under load with no "rest" for more than 5 minutes at a time, or
  • stalling a servo for more than a few seconds. Stalling means the servo is commanded to go to a certain position, but something physically prevents it from getting there, such as an obstacle or another robot during a competition. A few seconds generally won't cause a problem, but continuous stalling will rapidly heat the servo.

Here are some things you should avoid if you want your servos to last a long time:

  • Do not press down on the robot when it is running and the servos are under power. We have seen young children do this, and press with enough force to break several servos in just a few seconds.
  • Along these same lines, when you are installing the cap you need to press down on the robot to get the tabs inserted into their slots properly. But you should support the bottom of the robot with your hand while doing this. You should not press down on the cap to install it in a way that puts pressure on the legs.
  • Do not run the hexapod for long periods of time under constant motion. For example, do not enable demo mode with a high capacity battery and let the robot run for more than 5 minutes at a time with no rest. Eventually the servo motors may overheat. For contests and games, make a "round" of play last a maximum of 3 to 5 minutes. Letting the robot rest between strenuous routines will allow the servos to cool.
  • When programming the robot using ScratchX, it is important not to try to lift the entire hexapod body weight with fewer than 4 legs from a sitting position.
    • Once standing, as few as 3 legs can hold the robot's weight. But when standing up from a floor position, if you try to lift the robot's entire weight with, say, one leg, you will overstress that servo.
    • It is safest to write your programs while the robot is on the stand so you don't accidentally do something that will stress the servos. Once your program seems to work on the stand, try it on the floor for real. but if you see the program try to lift the robot's full weight with fewer than 4 legs, stop it immediately (or lift it off the floor and put it back on the stand for further debugging).
  • During competitions, stalling a motor may occur when two competitors attack each other, such as during a joust. If the legs of the opposing robots "lock up" for more than a few seconds, the referee should order the players to back off. If they do not, then the referee should physically separate them, wait 30 seconds for the servos to cool, then continue.
  • Do not attach objects to the hexapod that weigh more than 100 grams (about 4 ounces). This could cause too much stress on the knee servos, and over time will cause their lifespan to be reduced considerably. If you design attachments for the hexapod, keep them light!