Robot Stops Responding to Joystick and motors continue to run

We are running into a peculiar bug. Once in a while, while we are driving our robot, we will lose control of it and one, or multiple, motors will continue to run.

This happened to us in competition, and I thought it might have been a faulty controller - so I retired the joystick and brain.

But now we are seeing this happen more and more often during practice - to different robots with different joystick programs.

I asked our other teams, and they are also experiencing this problem.

Is this a know issue with the current firmware?

Thanks,

Cris

Hi crispierry,

We’re sorry that you have encountered this issue. The Robot Brain is set by default to stop all motors if it loses radio connection. To try to help resolve this issue, we have two questions.

Does this issue occur with the built-in Driver Control program, or with custom programs (such as from ROBOTC or Modkit)?

When this issue occurs, what is the LED on the Controller and Robot Brain doing? Is it blinking or solid?

Regards,

  • Art

Aloha crispierry,
We have also encountered this same problem after upgrading the firmware. We use Modkit. After we back our robot into the base where the first cube is located and hit solidly into this base the robot is very slow at going forward again.
Here are our observations:

  1. When we backed into the base on another try, we physically lifted up the robot immediately after the stop and notice the wheels rotated at least a half revolution before stopping. This is with our driver not touching the joystick controls.

  2. The robot seems to drive fine (forward and reverse) as long as we don’t back solidly and hit the base in reverse.

Another thing we noticed after the firmware update is that the program we wrote in Modkit was erased from the brain (understandable) and erased from our cloud account (hmm)

I believe we are both encountering the same problem.

Any suggestions to solve this would be greatly appreciated.

Hi Art -

>>>Does this issue occur with the built-in Driver Control program, or with custom programs (such as from ROBOTC or Modkit)?

We only use custom programs with RobotC.

>>>When this issue occurs, what is the LED on the Controller and Robot Brain doing? Is it blinking or solid?

LED is still blinking.

We are running into this issue in almost every practice we hold. It happens about once every 20 runs.

Cris

I encountered similar issues today, where some but not all wheels keep turning, and the joystick has no control of the robot. We are running our own custom program. It happens 2 times within 1 hour. The LED shows “I2C error on motors on port 10 to 12”.
My code is compiled with code optimization set to “None – Best for Debugging”, and RobotC version 4.27.

John

Hi crispierry,

Could you post your ROBOTC program code here so we can help debug it?

The LED on the Controller and Robot Brain blinks when there is active radio connection, and is solid when on tether or if there is no radio connection. Since the LEDs are still blinking, there might be a loop in your program or something waiting for a sensor input that might cause this momentary lack of control.

Regards,

  • Art

Here is one of the source codes for the simplest of our robots

Let me know if you spot anything wrong in the code

Cris

Note that in this program, we are not waiting for any sensor input.

Thanks for this information and the sample code; it looks like this file is referencing a custom include file, “utils.h”. If possible, can you send the simplest version of a program that replicates this error? This will help us debug this issue quicker and easier (we’ll be looking into this on our end as well, but having a simple program to base our research on will help expedite the issue).

Thanks in advance!

Hi John - i will send a simpler one later (out of the country right now).

Aloha Art,
Could VEX IQ provide teams with access to the previous firmware and allow teams to update either one? It really seems that the new firmware is affecting our teams here in Hawaii. Having the option to upload the previous firmware will help many teams. Could you provide a link and instructions to load the previous firmware? Our teams would like to desperately go back to the previous firmware.

Aloha ipanavigator,

We are currently investigating a bug fix for this behavior. In the interim, it is possible to revert back to the previous firmware instructions. Please send an email to our technical support folks at [email protected] for help with this. Unfortunately the firmware files are too large to attach to a forum post.

Regards,

  • Art

Thank you Art. I just sent a request to [email protected] for a copy of the previous firmware. Much Appreciated.

I am glad to hear this problem may soon be fixed. We are still running into it on maybe 2-5% of our practice runs. However, considering the investment that we have made with the joystick and autonomous software, we are not planning to revert back to an old firmware. We have a competition this Saturday, and we will just keep our fingers crossed that this bug won’t happen during a live match.

Can’t wait for the new firmware to be released!

Best of luck this Saturday crispierry. I’m glad that the bugs haven’t affected you that much. The bug affected us a lot. For example, we were scoring 105 points in driver skill prior to the updates. After the update in driver skills we scored 43 points. Huge difference. Largely because of the lags in switching between forward and reverse motion. I’m looking forward to the new firmware also.

105 is not too shabby! where do you compete?

Aloha crispierry,

We compete all over Hawaii. Oahu, Maui and the Big Island. We also competed in Dongguan, China at the 2014 Asia-Pacific Championships in December where we won the Teamwork Champion and Excellence Award in the middle school division. I guess that makes our team the #1 USA team in VEX IQ Middle School division in China. Very grateful. Go USA!! I forgot the name of the school we were teamed up with but they were awesome!! Their coach and kids were great. They are #1 also. Last year, two of our teams were also the Hawaii State Champions in VEX IQ. Currently, all of the VEX IQ competitions that we participated in we have won the Teamwork Champion award. As the state competition rolls around we are definitely crossing our fingers. Anything could happen. I’d like to get this firmware issue resolved so that we can continue our practices.

We too have experienced this problem since the update and have posted several issues here as well as to support. The response was recognized as a program issue and not firmware. Now that many have the same issues, it has been identified as a bug. Glad it will be fixed soon.

We have experienced this problem 4 times (4 separate matches) in an actual tournament matches today. One common incident was that 3 times the robot turned right on its own and kept turning.

Several times the [x] was not able to turn off brain. Program was able to run, joystick continued to work in 2 incidents. The only way to turn it off was to lift robot and pull out the battery. Then turning on the brain again it was normal…

In addition, that was one instance where one team was controlling another teams robot on field. My understanding was that each controller module was unique. Not sure if this is just channel overlap or a freak chance. Just thought that was interesting.

Firmware brain 1.13 controller 1.04

Hello everyone,

While we are still investigating the bug in the Smart Motor firmware that is causing these issues, we have posted instructions and firmware files for manually reverting to the previous firmware on the Robot Brain, Controller, and Smart Motors. The guide is available here:

http://link.vex.com/vexiq/downloads/Reverting-to-VEX-IQ-Firmware-v1-12

We apologize for any inconveniences this may have caused, and we are working as fast as possible on testing a new update to resolve this issue.

Regards,

  • Art