Troubleshooting

It’s not always easy to figure out why a robotic system isn’t doing what’s expected!

The following is a set of general procedures that may help you debug your Hummingbird-based robot or electronics project. They are arranged in the order that they typically come up for us when helping train students and teachers who have no Hummingbird experience.

If you’re still having trouble contact us.

Check that Hummingbird is Connected

Make sure your Hummingbird is connected via USB to the computer. If the Hummingbird is in tethered mode, ensure that software such as the BirdBrain Robot Server or CREATE Lab Visual Programmer identifies the Hummingbird.

Once the software identifies the Hummingbird and connects to it, the green status LED will turn solidly on; if it is not connected it will fade on and off. If the Status LED is off or blinking, your Hummingbird is in Arduino mode and will need to be reverted to tethered mode before you can use it with the BirdBrain Robot Server or CREATE Lab Visual Programmer.

If the Hummingbird is in tethered mode and connects to BirdBrain’s programming software, go to the next troubleshooting step. If the Hummingbird is not connecting to your computer, contact us for help.

If the Hummingbird is in tethered mode and connects to BirdBrain’s programming software:

Go to the next troubleshooting step

If the Hummingbird is not connecting to your computer:

Contact us for help

Check Hummingbird Component Connections

Make sure that you have connected all of the components you are using to the Hummingbird correctly.

Common mistakes include connecting an LED or servo backwards, or connecting components that should go in one port to another port – connecting LEDs to the sensor ports, for example.

Review the Connecting Electronics tutorial and double check that all is as it should be.

Similarly, in the programs you create, ensure that your code is set to the right ports: a program that turns on an LED on port 1 will not do anything on a Hummingbird that only has an LED connected to LED port 2.

If Motors or Servos Do Not Work, Check Motor Power

If your project uses gear motors or servos:

You must plug in motor power.

Ensure that power is plugged into the barrel jack on the left side of the board, and that the orange LED indicator light is on.

Perform a Software Reset

If your program was working but seems to no longer run, or if your computer went to sleep and your program no longer responds, try resetting the software using the following procedure:

  1. Save your work.
  2. Close the programming software you’re using. Note that you do not typically need to close Scratch or Snap!, but you will need to quit out of the BirdBrain Robot Server or the CREATE Lab Visual Programmer.
  3. Disconnect the Hummingbird from USB AND from Motor Power.
  4. Reconnect the Hummingbird to USB and then to Motor Power.
  5. Reopen the BirdBrain Robot Server or CREATE Lab Visual Programmer
  6. Re-run your program. If it works, then the issue was probably a software glitch.

If it does not work:

Go to the next troubleshooting step

Test Components in the Programming Interface or Run an Example Program

If your program does not appear to be working in Scratch, or Snap!, try simply clicking on Hummingbird blocks corresponding to the outputs or sensors you have connected to cause actions.

If the program isn’t working in the CREATE Lab Visual Programmer, you can use the Expression builder interface to test any attached outputs, and you can use the Sensor structure in the sequence block to test a sensor.

For text-based environments such as Arduino or Python, try running an example program that uses the part or parts you are currently using.

If our examples do not seem to work:

Go to the next troubleshooting step

Test Components

It is possible that you have either a non-functional component or a broken port on your Hummingbird. To test if a part is not functioning, do the following:

  1. Place a replacement component in the same port and then run either your program or an example program to see if it works. With the exception of the sensors, Hummingbird kits come with at least two of each component type.
  2. If testing a sensor, you may need to use a different sensor type, but you can still observe if the new sensor is behaving properly to rule out a problem with the sensor port.
  3. To verify that the component works, place it in a different port and then program that port to turn on the output or read from the sensor.
  4. If the replacement parts also do not work, you may have a broken port.

If you end up having a broken component or broken port on your Hummingbird, please contact us to see if it can be replaced under our warranty.

Contact us

No piece of hardware or software is perfect, and the Finch, as a combination of hardware and software, can sometimes be doubly prone to problems.  If you’re having a problem with your Finch, read through the following set of issues and see if one matches your experience.

If you’re still having trouble contact us.

Finch Doesn't See an Obstacle

Description: The Finch doesn’t seem to detect an obstacle.

Cause:  The Finch uses two infrared LEDs and an infrared receiver to detect obstacles. Using infrared is a low-cost and effective way to detect most obstacles, but it is limited:

  • The obstacle must be approximately 2”-4” from the sensor to be detected.
  • Dark and non-reflective objects are harder to detect.
  • Narrow vertical objects like chair legs may not be detected.
  • Certain black plastics transmit infrared light (they look like glass in the IR spectrum) and so don’t reflect sufficiently to be detected.

We strongly recommend using lightly colored obstacles like cardboard boxes or white office paper. Covering obstacles in tin foil increases responsiveness significantly.

Finch Doesn't Move Straight/Turn Accurately

Description: The Finch’s movements are not repeatable – a timed turn that moved 90 degrees might move 110 degrees the next time.

Cause: The Finch’s tether makes repeatable movements difficult – turns cause the tether to twist, causing a spring force that tends to resist continued turning in the same direction. The tether may also drag on the Finch, causing it to turn slightly when it should move straight. You can minimize the effect of the tether by:

  • Holding the tether overhead while the Finch is moving (see photo)
  • Driving Finch on smooth flooring – carpeting will tend to slow down the Finch.
  • Turn at slow speeds.
  • Use sensors to help the Finch move more accurately by using cues in its environment. For example, the Finch can follow a light source or a wall.
Finch Randomly Disconnects from USB

Description: The Finch seems to lose connection with the computer while running a program.

Cause: USB plugs and cables weaken over time and occasionally this affects the stability of the Finch’s connection to the computer. Try using a cable tie or tape to fasten the USB cable to the Finch, providing strain relief, so that there is little movement of the cable near the plug. If the issue is severe, and your Finch is less than one year old, please contact us to request a replacement.