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HOW TO: Wiring the Scorpion Nano TO A BOT.
A BRIEF SCORPION NANO MANUAL: USING A VIPER AS A WIRING EXAMPLE:
Assembly Concepts: OrientationAll of the instructions for assembling and wiring a bot are based on a critical concept: Orientation. In this case, we’ll use Fingertech’s Viper as our example bot. It is very important that you get the right and left sides of the bot oriented correctly as you’re assembling and wiring it. If you get the orientation wrong, your bot won’t drive correctly.
How to orient:With the back of the bot near to you, and the front of the bot facing away from you, the right side will be where your right hand is, and the left side will be where your left hand is. If you’re in doubt, refer to the picture.
Assembly Concepts: Polarity
Another important idea is the idea of polarity. Technically, what polarity means is that some electronics and components have an orientation. The electrons need to flow in a particular direction. If the part is oriented or connected incorrectly, the part may not work, may work incorrectly, may even overheat or blow up.
When Wiring the Scorpion Nano, the most important polarity to pay attention to when connecting the drive train is the motor polarity. If the wires are connected correctly, the motor will drive in a certain direction. Reversing the wires will cause the motor to run in the opposite direction: the bot will drive backward. In the case of our Viper example, the Silver Spark motors that are the drive motors for the Viper each have a polarity mark. The polarity mark on these particular motors is a red dot near one of the connection lugs. See the picture for details.
Wiring the Scorpion Nano: the Basic Scorpion Nano Wiring Diagram, INCLUDING Receiver Connections:
.IMPORTANT UPDATE: Robot Power has just changed their Scorpion Nano. In a few isolated cases, providing power and ground from two sources to the receiver can create issues. To solve this, ROBOT POWER HAS CHANGED FROM THREE wires on each connection to a single wire on the second connection. one connection has three wires, power, ground, and signal. These are typically red, black, and white, or brown, red, and orange. The other connection ONLY has the signal connection, colored yellow. See below for more information.
Note: Robot Power has also added glue as a strain relief on the receiver connections. this does not affect the operation of the board, only protects the wiring connections from breakage.
Think of this post as a basic Scorpion Nano Manual: giving you all of the necessary information to be successful at wiring and using the Scorpion Nano to drive a combat bot.
- Note: On the board near the wires, you’ll see a silkscreen that says “TH” for one set of wires and “ST” for another. These indicate “STeering” and “THrottle” channels. For most radios, steering should be Channel #1 and Throttle should be Channel #2.
- Note: Going forward, Nanos will be shipping with just a single wire conductor on the ST channel.
Assembly Steps – Motor Connections:
- Wiring the Scorpion Nano requires soldered connections..
- Solder the blue wire onto one Silver Spark motor’s red terminal. Look for the red polarity mark next to the connection lug. Connect the white wire to the motor’s second terminal. This will be the RIGHT motor.
- Connect the green wire to the left motor’s red-dot terminal. Connect the yellow wire to the motor’s other terminal. This will be the LEFT motor.
- Remember your orientation!
Check Your Motor Connections:
Polarity problems are one of the biggest issues for a bot to fail to drive correctly. Here’s a simple diagram to help you check your wiring. Match the wire color to the dot and the motors to the correct side of the bot.
- RIGHT motor: Blue wire –> Red Dot
- LEFT motor: Green wire –> Red dot.
- Remember your orientation!
If your motors don’t have a polarity marker, or they do and it doesn’t seem to make the motor spin in the right direction, first check your wiring and that you have the right channel plugged into the right slot on the receiver, and your signal is mixed. Then swap wires so that the right motor turns in the proper direction to drive the bot forward on that side.
For problems, see our troubleshooting guide (soon to be published)
Checking your wiring
- See the diagram for on overview of how the wiring looks in the bot chassis.
- Make sure the polarity of the wires attached to the motors are correct and the motor orientation (left vs. right) is also correct.
Connecting to Power
- The Scorpion Nano must be powered. The black wire should be connected to the negative power source. The red wire must be connected to the positive power source.
- In the case of the example Viper kit used here, the power wires are connected through the mini terminal blocks. You can see them in the diagram as small red and black blocks on the diagram.
Identifying Receiver Connections:
- Identify the connectors on the Scorpion Nano so that you are clear which is channel 1 and channel 2. See the diagram.
- The Channel 1 wires and connector are the ones that are close to the larger, square, black integrated circuit
- The Channel 2 wires and connector are the ones that are closest to the small switch in the center of the board near one edge.
Assembly Steps – Making the Receiver Connections:
- These instructions are based on the Turnigy or Hobby King T6A transmitter/receiver.
- Identify the connectors for the proper channels. Refer to the diagram above.
- Plug the ESC connector from CH1 on the Nano to CH1 of the 2.4GHz receiver.
- Plug the ESC connector from CH2 on the Nano to CH2 of the 2.4GHz receiver.
- Plug the bind plug, which is a simple black wire loop connected to a black connector, into the battery slot. This slot is labeled “BAT,” for battery. There is no polarity; the bind plug can be oriented in any direction.
- NOTE: The bind plug is used only to bind the receiver to the transmitter. Once this is complete, remove the bind plug or your bot will not react correctly.
- NOTE: Your transmitter and receiver may be different, look different, and may bind differently. Refer to your TX/RX manual.
TIP: The channel numbers can be seen on the receiver label immediately to the left of the pins, labeled CH1 through CH6, starting at the bottom, with the top-most labeled BAT (battery).
CRITICAL TO QUALITY: Make certain to ensure that the black wire in each connector faces to the OUTSIDE of the receiver. See the wiring diagram.
TIP: Wait until all the mechanicals are in before permanently mounting the receiver in position.
IMPORTANT UPDATE: Robot Power has just changed their Scorpion Nano. In a few isolated cases, providing power and ground from two sources to the receiver can create issues. To solve this, ROBOT POWER HAS CHANGED FROM THREE wires on each connection to a single wire on the second connection. one connection has three wires, power, ground, and signal. These are typically red, black, and white, or brown, red, and orange. The other connection ONLY has the signal connection, colored yellow. See below for more information.
A Note on Nanos and Mixing:
Scorpion Nanos come with a great built-in capability: channel mixing. The board actually has on-board mixing– it will take an unmixed signal and mix it. That capability can be turned on or off by leaving a jumper in place or cutting out the jumper.
We’ve been told that when you have mixing set up in your transmitter, Tx mixing plus onboard mixing cancel each other out, leaving the signal unmixed.
This picture shows a mix jumper installed.
TIP: One easy way to tell if your mixing is canceling itself out is to move the throttle stick on the right to the top diagonal right. If this causes the bot to move forward, your signal is unmixed.
The fix is simple: Clip out the small white “mix” jumper and the onboard mixing will be disabled. The bot should drive correctly after that. PRO TIP: Cut and bend the MIX jumper so it’s disconnected but still mostly in place. This allows it to be bent back into contact and re-soldered if MIXing is desired later.
If you are going to use the on-board mixing of the Nano, here are some tips and tricks to get it working correctly. If your motors don’t have a polarity mark, or you can’t figure out the wiring, and you’re not using the transmitter’s mixing, do this:
- Set the radio to the default trim condition with transmitter mixing off and channel reversing to “normal” (i.e., non-reversed).
- Plug the receiver and power into the Nano. Then push the throttle control (stick or trigger etc.) “forward”. Touch the motor wires to the left and right motor terminals, in turn, to make sure they both are spinning in the correct direction to make the robot move forward. Make sure you mark somehow which wire worked correctly on which terminal.
- Once this is OK the motors wires can be soldered.
- Now check the steering function. The motors should spin in the correct direction to make the robot turn to the indicated direction i.e. a left turn is right motor forward and left motor reverse. If not correct then activate channel reversing for steering only.
MY BOT’S NOT DRIVING RIGHT! TROUBLESHOOTING:
- If Nano MIX is enabled (in other words, you haven’t cut the jumper on the board) and transmitter mixing is on you’ll get strange behavior. Examples include:
- No response to the steering channel
- Always turning when trying to go straight.
- One motor won’t drive at all
What’s happening here is that the transmitter mix and Nano mix are canceling each other out in some way.
- PRO TIP: We suggest disabling mixing activation from the switches on the transmitter or setting all switch positions to no mix. That will prevent accidentally turning on mixing by hitting the switch.
- PRO TIP: A reverse throttle (not steering) mix on a switch is useful for inverted driving. So putting that one on a switch is a nice feature if you have a programmable radio.
You should NOT connect a weapon ESC AND the Nano with BEC intact to the same receiver. It may work or it may not work properly.
Pull (or clip) the center wire out of the TH channel RC cable to disconnect the Nano BEC.
PRO TIP: Pull the wire out and bend it back and wrap it with tape when you disconnect the Nano BEC. This lets you reinstall it easily if desired without soldering.
Radio calibration procedure.This isn’t as important as it used to be with the super adjustable computer radios now. But for a lowest cost 2-ch radio it might be needed.Basically the steps to calibrate the Nano to the specific radio signal range are as follows:
- No motors are needed for this but they don’t interfere so it can be done in a fully wired robot.
- Turn on TX and apply power to Nano and receiver with RC wires plugged in
- Wait for solid LED on Nano which indicates RC signals detected.
- Controls should be centered and trims should be at neutral i.e. default radio factory condition but with the channel reversing set as you like it.
- Press and hold the CAL button until the LED goes out (about 3-5 seconds). Then release CAL button. LED should blink.
- Move the controls to the extremes of travel several times both together and individually.
- Press and release the CAL button to permanently store the settings.
To do a factory reset.
- Follow steps 4 and 6 above with TX OFF and/or without the RX plugged in.
- This sets the Nano to the internally stored default Futaba RC signal range which should be close enough to get started on every radio that outputs standard RC PWM signals.
Here are the configuration settings that we use on our bots. All of the wiring diagrams work 100% correctly with a known good Viper, using this configuration on a T6A transmitter and the wiring as shown.
You can find the Turborix programmer for the T6A here. It is an awesome program that runs on a Mac. We love it.
Hope ALL OF this helps you with your Scorpion Nano!
TROUBLESHOOTING THE SCORPION NANO.
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