Vex needs a new micro-controller


#1

Vex needs to come out with a micro computer like the Raspberry Pi 3 (https://www.adafruit.com/products/3055) or Arduino (https://store-usa.arduino.cc/products/a000062) and price it at a reasonable price.


#2

What particular features are you looking for? Price is just one aspect of selecting a solution.


#3

I am not sure how much you actually know about micro controllers. Just want to add that something like a Raspberry Pi would absolutely terrible for something like motor control. Raw digital sensors and PWM requires a lot lower level access than an actual computer can provide.

Arduino mega is substantially weaker than a VEX cortex.
https://store-usa.arduino.cc/products/a000067

A Due is to be honest decently close in specs to a cortex. Due is the first arduino to actually allow all digital ports to be configured to act as interrupts, something a cortex has had for 6 years. And the cortex comes with lots of components that are not included on an arduino.

Have you ran into an issue with the amount of power that a cortex provides?


#4

i believe that they should lower the price but as @tabor473 was saying if we were to do that we wouldn’t be able to get as efficient controllers due to them being more cheaply made and the board wouldn’t work as well. If we were able to do it it would also have to change how the controller is made/looks in such a way that there would have to be too many changes that would end up changing the game itself.


#5

VEX announced to a group of event partners that they were working on their next-generation controller, and in 2016 they talked about it at VEX Worlds. It’s coming, but I don’t know when.


#6

At the Event Partner Summit (Summer 2016) they also indicated that there should be an updates on changes to the Microcontroller, Joystick and Motors coming.

I look forward to an update to the electronics. I hope to see something at Worlds.


#7

I’ve done a fair bit of embedded development. I look forward to working with whatever new hardware they make available. I assume they’ll make some things easier to use, with different interfaces, and a different interrupt structure. I expect they’ll change power handling some way, as that’s probably the biggest day-to-day complaint. Maybe they’ll also use integral wifi, bluetooth, near field, ZigBee, or something like that. And probably, they’ll better address I2C or other multidrop addressable interfaces. They may add an integrated panel interface, maybe someth like what they have in the VEX IQ brain. It will be cool to have all that.

But I am completely sure that no VRC game to date has required anything near the full computing resources of the current VEX Cortex.


#8

I would like to see higher-current PTCs in the Cortex (ideally around 12-15A) and more storage for files. I would also like to see a screen on the joystick and a way to measure current flowing through a motor port, or a motor if we get new ones.


#9

No I haven’t had problems with the cortex.
The arduino has Shields that have motor, servo, and sensor control. It also doesn’t need a Shield to use a sensor, motor, or servo. The cortex is over priced. The arduino UNO R3 is only 24.95$ the cortex is 249.99$, that is a rely big price difference.


#10

Arduino is also a developer platform, the Vex Cortex is finished product. Being able to easily plug in your motors and sensors into a device is better than breadboarding your robot. The cortex can take some abuse. Like it was said earlier, the Due is more what you would reference based on IO and power. At $37 for the Due, the Vex Cortex is still much more expensive, but the initial learning curve is much lower.


#11

There are very few robotics platforms that have the such a high level of robust flexibility that are also approachable for a wide audience (student, teacher, hobbyist, novice, expert, etc). VEXIQ and VEX EDR is extremely flexible and capable, yet still understandable for any level of skill.

When you look at the cost of any comparable systems with those advantages, VEX stands out as one of the (if not the) most affordable.

I’ve watched attempts to make use of Arduinos for robotics competitions, but it never fails that the less savy teams get bogged down by support issues. The steeper learning curve appears to limit success to a handful of teachers/mentors that have the skillset & time to deal with those issues. It fails to see a broader appeal.

In summary, cost shouldn’t be the only metric you look at when evaluating the value of a system. There are several other metrics that matter along with cost.


#12

I disagree with your point about the current breakers. VEX is an educational platform, being able to distribute the current over your breakers is an important lesson to learn. I don’t think vex should release new products just to make things easier for teams. Once a team is at a point where they are drawing enough current to trip the breakers in a cortex, they are at a point where they should be learning why that is happening. It’s similar to the “we need more powerful motors” discussion - the playing field is even, if things are easier students are only going to learn less. People need to learn to work around these issues. One of the biggest challenges in engineering is working with constraints.

The most important thing to me with a micro-controller for a competitive robotics platform is reliability. If VEX were to reduce the quality of the cortex, reliability would almost certainly decrease as well. Nothing is more heartbreaking than to see a team lose because their connection cut out.

The cortex should be a one off purchase. With the small quantity vex sells, I don’t see how they can cover their R&D costs with a $37 micro-controller. You can’t have both more features and a low price. In short, VEX really doesn’t need a new controller. Sure it would be cool, but are you going to learn more or build better robots because of it? Probably not.


#13

They always say pick one of the 3:

Cheap
Good
Fast

Gotta say the Cortex fits 2 of those at best. I’ll let you guess which ones.


#14

@OscarNVCC Actually it’s Cheap, Good, Fast pick two, the other one changes with the choices. (In my world, people pick good and fast and then are astounded by how much they cost. )

I’ve watched the VEX platform change from PIC 0.5 - (Crystal stuff was a pain) to PIC w VEXNET (Backpacks for everyone!) to Cortex to the IQ controller.

I’ve also watched motor sizes grow and motor use grow and more importantly abuse of motors grow.

@jacko makes the key point -> VEX’s market is education. If you looked at the number of VEX kits in classrooms vs VEX kits as part of VRC, you’d really wonder why from a business standpoint they put such efforts into VRC at all. Teachers care about it working, not breaking, easy to use, not breaking, working and hard to break. Teacher money comes out of a school budget. Teachers are doing simple projects, not 12 motor monsters that run at full tilt for 60 seconds with a dozen sensors on it.

What I’d like to see is the IQ “brain” and an “brain extender”. Brain extender is a “brain” that runs a special program that slaves it to the “brain”. You would just then connect the two with a short cable and now you have 22 ports AND two battery packs. Likewise some new IQ code to allow two Joysticks to connect with the tether connection to join them and give partner control. I really hate the existing extender and this gives a way to really split motors across two battery packs.

Next would be a line of VEXIQ motors that have bosses on them to allow screw mounting. (Actually just screwing a small plate onto the VRC robot and then snapping the motor onto the plate with IQ connectors could work. With 6 IQ pins, those motors are NOT coming off. The motors have IME built in, so that is a bonus for teams that haven’t switched to the IME.

Then create a bigger version of the motor, for those extra power needs. The bigger motors would be extra strength shaft sized to start (with the adapter to downsize to standard shaft)

Creation of a standalone rotational sensor and something like a “limit switch” would round out the existing suite of sensors.

Lastly is “Motor Controller 99” adapts the VEXIQ brain to standard “393 two wire motors” to ease the transition.

This gives a growth path for the 5000 VRC teams and allows the 50,000 VIQ teams to transition to VRC.


#15

If you were to take apart the CORTEX and see the mainboard, you can see that the device isn’t as complex as I thought it should be. The CORTEX motherboard still seems to have a ton more space for things that can be added, maybe more computing power or another port for SD? I believe that VEX isn’t really meant to be a starter robotics system, but I think it should start getting more advanced in the creation of a robot. They should have a motherboard where you can add onto it, get you into the electrical engineering mechanics. Then when done, you will have a shell that you will put the motherboard in for protection. The CORTEX seems just too limited, and it seems like it should have the option to add/remove components if needed so you can allow more abilities, computing power, and other things whenever it seems needed. I’m not saying this will be a thing that you HAVE to do, I’m saying that this should be an option to get into the more advanced mechanics of engineering to educate about not just mechanical engineering, but also electrical. If you were to compare VEX to FIRST, you will realize that FIRST is by far much more open sourced and less restricted to your abilities for achieving certain tasks. I believe that VEX needs to be less strict with some rules, and maybe also allowing 3D printing of components, soldering, and other abilities will be a really good idea for the future of VEX to improve the education of students.


#16

In terms of inputs/outputs, power, breakers, etc., the CORTEX is great. Whoever said that student need to learn to work within constraints hit the nail on the head. Good teams will push the limits, and push them well, no matter what you give them. Weaker teams will complain that there isn’t enough power or the motors keep burning out.

What is needed is durability and some updated functionality. My high schoolers do some of the dumbest things, but that just comes with the age. Learning from mistakes is an essential part of the process, and I like being able to let them explore. But when they start wiggling the battery plug, I cringe knowing that I already have two cortexes that have been damaged by this. When they lose the motor port clip for the 10th time, I want to scream. When we have to keep unplugging the VexNet key to upload our program via usb, it’s a pain in the butt (and it eventually wears on the connections). I try to teach not to do these things, but … freshmen.

  1. We shouldn’t have to buy a separate LCD screen. Build one into the next cortex.
  2. Memory is cheap these days, so improve it or have a micro SD slot. Allowing for multiple programs would be great (though I do love teaching ways to make different autonomous selectable).
  3. Either make wireless programming easier or put a second USB port on the cortex.
  4. Joysticks need more durable competition plugs. Kids are emotional from a match and just pull the cable out, or walk away on accident. The little tabs should be metal. They also should cost MUCH less.
  5. The way things plug into the cortex could be improved. I understand that ease of attachment/removal and security of that attachment are competing values, but I think improvements can be made.

I say all this hoping that they actually have a replacement ready to unveil at worlds, in which case my suggestions are too late.


#17

I understand your points. But here are my thoughts as someone who been a part of VEX since before it was VEX. I must start by saying that the FIRST programs are good programs and the students that compete in them learn many valuable things. I have chosen to align with VEX however.

  1. To me, the VEX philosophy has always been to keep the cost as reasonable as possible and to keep the playing field as even as possible. Allowing teams unfettered access to add things to the motherboard of the onboard processor as well as 3d parts will give, in my opinion, an incredible unfair advantage to teams who have access to LOTS of money and high powered engineering mentors/coaches. The range of people involved in VEX is quite large, from Tech Ed teachers who have never programmed any code to the aforementioned high powered engineers.
  2. Allowing of 3d printed parts also fits under trying to keep the playing field as even as possible. Although the availability of 3d printers is growing, there are many teams that don’t have them nor the means to acquire them. There has been indications from RECF that this issue might be re-opened in the future as the availability/accessibility becomes greater.
  3. I think a major difference between FIRST and VEX is the amount of money that it takes to get involved in the programs. FIRST programs, whether it be FLL, FTC or FRC require far more money to compete than their comparable VEX programs. I would NOT want to see VEX become FIRST. If one wants to deal with the things that FIRST offers, it is there.
  4. The VEX platform is also the platform for PLTW and as such needs to be accessible to a wide range of teachers abilities as well.
  5. There are other ways for students to learn the things you suggest, I personally have no problem with VEX as it stands.
  6. My understanding, and it has been alluded to above, is that we will see a new onboard processor for VEX soon, possibly introduced at Worlds. We will just have to wait and see what that entails.

#18

Interesting thread but considering the announcement last summer at the event partner summit in Louisville it may all be moot. The new cortex by whatever clever name that was available for trademark is more than likely sitting on a shelf in the warehouse in Greenville at this moment and if it isn’t yet just hope our politics with off-shore manufacturing countries remains calm for at least the near future. My wish is for a highly incentivized exchange program as the scope of replacing potentially the cortex, joystick, vexnet and motors at one time is frightening as unlike school districts vex clubs do not have taxing powers.


#19

Completely agree. It’s hard to imagine that it’s not already here, or at least loaded in a container and on the way. For cheap shipment, there’s at least a 6 week transit time, and 8 weeks is better. (We have to ship fireworks by container ship, so the pyro community knows a bit about multi-modal logistics.)

I assume there will be a period during which both systems are in heavy use. But you have to imagine a serious incentive plan is the only way to speed the changeover, and quell the pitchfork-laden crowds. Because a full retail changeover is going to be really, really expensive. I believe EC3 has 13 current teams, with a retail electronics cost of about $1500 per team. That doesn’t include the use by the engineering program. I don’t know how many systems each PLTW program uses. Hardin County Schools has one middle school, 3 high schools, and the EC3 facility all with a PLTW program. Retail electronics cost is…scary.

Clubs, though, largely won’t be able to seek grants.

You and I may have to host a bake sale…


#20

Yeah I heard rumors last year that they pulled the release of it right before 2016 VEX Worlds. Hopefully we get it this year, and hopefully it’s ready to purchase at Worlds.

But I’ll have 6 VEX Teams next year, and I’ll be putting each one on the new system if available.

You think at $350 * 6 = $2100.

That’s a hefty price for new brains, not even including the cost of motors.