This hack allows you to ditch the 6xAA battery holder and replace it with a nice RC battery, like those used on RC cars and boats. In addition, with this hack you can have a charging port that is easily accessible and allows you to charge the battery without even removing it from Mimsy!
Difficulty: Easy Edit
Time: About 10 minutes Edit
Expense: A few dollars for Tamiya connectors, of course an RC battery costs more, about $12 to $20 depending on capacity. You will also need a charger for your RC battery, low cost ones are $10, smart chargers and high speed chargers are more. Edit
Materials Required Edit
- Two Tamiya connectors, one male and one female. These can be purchased from websites that have RC (remote control) parts. They only cost a few dollars.
- A 7.2 volt NIMH RC battery with a Tamiya plug. These come in many capacities, you will want one that is long and thin as shown in the photo here.
- A 7.2 volt NIMH RC battery charger with Tamiya plug.
WARNING: It is strongly recommended that you use a 7.2 volt NIMH battery. Do not use a rechargable battery of greater than 8.4 volts, as you can damage your Nano controller by doing that.
(Reason: for those of you who are technical, there's a voltage divider used to allow Mimsy to read its battery level. That divider feeds 50% of the battery voltage to an analog pin. Analog pins can only take 5 volts max. If you were to use, for example, a 9.6 volt battery, when fully charged it will actually be over 10 volts. And half of that is over 5 volts, and that will destroy your controller.)
- Turn power OFF.
- Remove the front grill and control panel so you have access to the electrical system.
- Pull out the 6xAA battery holder and remove the batteries just to be sure there is no power to the system.
- Follow the battery holder's red wire to the WAGO connector that has the "positive bus" bundle. Open the WAGO clip and remove the battery holder's red wire. Insert the red wires from the two Tamiya connectors in the Wago clip and then secure the lever to lock in place.
- Do the same thing for the black wire. Trace the battery holder to its WAGO connector, open the lever, remove it, then plug in the black wires from the two Tamiya connectors.
- Move the battery rail near the back (LCD side) of the robot from its default slot into its extended slot. That should provide enough room for most RC 7.2 volt batteries to fit. If not, just remove it and use a thick rubber band or a piece of adhesive velcro to secure the battery to the bottom of the robot.
- Place the RC battery in the robot, connect it to the matching Tamiya connector. You are ready to roll! Turn on the robot to see if it powers up. If not, check connections and make sure its charged.
- Route the other Tamiya connector to a location that is easy to get to for charging. For example, toward the front grill by the bottom fence so you can reach it easily.
- You can charge the battery by turning the robot OFF, then plugging the other Tamaya connector into the charger. You should probably not run the robot while it is plugged in to the charger, you may draw too much current and damage the charger.
- Remember that if it's not a smart charger you need to unplug it when it's fully charged. Follow all manufacturer directions!