Twenty-seven Ideas Based on This Year's Expereince

VEX V5 General Discussion New Product Ideas
1

The following ideas are limited to parts that I think could be fabricated by making small changes to those already existing:

  1. Create all metal parts in 2.5 inch increments out to 17.5 inches as well as in 0.5, 1.0, 1.5 and 2.0 inch lengths. Cutting and finishing parts is time-consuming. A more complete set of parts would allow teams with tight schedules to spend more time developing and experimenting as opposed to fabricating. It would also assist in being able to reuse parts.

  2. Create an aluminum version of all steel parts.

  3. Stamp aluminum parts with a pattern to easily distinguish them from steel.

  4. Create pillow blocks in longer lengths (up to 7.5 inches).

  5. Create double-wide versions of all plastic gears.

  6. Predrill all but smallest gears with mounting holes.

  7. Fabricate tank-tread chain without treads for use with heavier loads.

  8. Fabricate tank-tread with predrilled holes for attachment of wire-ties (may need four holes per tread).

  9. Create at tread with holes aligned such that it can be secured to metal parts.

  10. Possibly create axles from stronger steel (15 & 17.5 inches also, see above).

  11. Please, please, please add torx-head fasteners.

  12. Create standoffs that fit inside channel.

  13. Create a kit that allows users to fabricate custom length cables.

  14. Provide a plastic snap fitting that holds wire connectors together.

  15. Sell the battery hold-downs as a separate part; they tend to break fairly easily.

  16. Modify the micro-controller housing to incluse a spring clip or wire-tie points for securing incoming cables.

  17. Provide a “dry” lubricant that can be used with slides and possibly gears. It cannot be create a mess or stain clothes etc. I have no idea if such a material exists or if this is even a good suggestion. Given that Vex is designed to be reused, the wrong material might end up everywhere—including on screw threads that are already a problem.

  18. Create a more functional set of tools that includes nut drivers, and allen wrenches with handles (or even better, torx heads). A very light-weight battery operated driver might also be useful for teams that are not composed of burly boys. This proved invaluable for the 13 year old girls on my team.

Ok, those were fairly easy. Here are some tougher ones:

  1. Create motors that either work or fail, but do not have an intermediate state where they appear to work but then fail a short while after being put under load. At the very least create a way to accurately determine a motor’s state. Determining which, if any, motor has a problem becomes a real challenge when two or four motors are ganged together.

  2. Add a micro switch to motors that allows them to be reversed without having to change programming. This would simplify using them with Y cables.

  3. Change motor wire lead-in to opposite end of case; currently it is always facing in the direction of axles, gears etc.

  4. Create a stronger motor. Possibly just gang two existing motors inside a larger case.

  5. Add encoder function to motor (highly desirable).

  6. Add two limit switch interfaces to motors (somewhat desirable).

  7. Current servo is inaccurate and too limited in range. It really needs at least 180 degrees of motion. One solution is to give it 1440 degrees of rotation so that it can be geared down for power and accuracy. Alternatively, if encoder function is built into standard motor, with limit switch functionality also, an improved servo might not even be needed.

  8. There seems to be a disconnect between some batteries and some charging stations. I have not identified a pattern, but occasionally stations will double-blink indicating a bad battery, but when the battery is placed in another station, it works fine. Note all batteries have been properly inserted since day-one. This creates an uncertainty that is not acceptable during competitions.

  9. Finally, track down the cause of RF problems at championships. If this requires new equipment, so be it. Reliability is far more important than cost when competing.

Hope you find these ideas useful.

–Bill Wiley
Coach, Vexy Things

2

The answer to 27 is this. At the competitions the teams in queuing were using their robots with crystals in at the same time as a match thus creating two signals on the same frequency which caused problems for the teams on the field. This is not a Technical or hardware issue but a problem on miscommunication and poor education. My team knew not to run the robots with the crystals in but I never once heard any announcements informing teams that they should not run their robots with crystals in, even if the robot is tethered.

3

Although this was a source of some of the problems encountered during the matches, it seems to have become the defacto standard reason that teams use to account for most of the problems they encountered. I know that my team had two such matches that the students to this date would probably swear under oath that it was problems with field controls, crystals or some other form of external interference. This may very well have been the case, especially with the duplicate set of crystals being used by both fields. However there are other possible reasons for things not going as they should during matches.

Here is a list of other possible causes a for robot not operating properly. The solutions to some of these are totally within the control of teams to mitigate or totally eliminate from competition. These are items that I have personally noted or observed during the build season and/or other competion events.

  1. Crystals are not properly seated in the receiver on your robot or the transmitter.
  2. Yellow cable is not properly plugged into the receiver or robot controller.
  3. Sensor/motor/servo cable is not plugged into the correct port.
  4. Sensor/motor/servo cable is not fully plugged in properly
  5. Sensor/motor is overloaded and shuts down due to thermal overload
  6. Antenna is not fully extended on your transmitter
  7. Antenna on your receiver is not installed for optimal reception
  8. Tether cable is not properly installed into the transmitter
  9. Robot received a bad program download
  10. Last minute untested program changes downloaded to your robot
  11. Robot/Transmitter batteries not fully charged
  12. User or master code has been corrupted
  13. Incorrect competition template was used
  14. Wrong library was used with MPLab
  15. Incorrect startup sequence used prior to the beginning of the match

Other potential problems that you maybe able to check before your match starts.
16. Tether not properly plugged into the field controls
17. Damaged tether cable connecting field controls to your transmitter

Now… this is not an attempt to minimize the problems that occured due to duplicate crystals in use at the same time. However, in addition to FIRST implementing a set of procedures that teams must use when queing up to compete, it is just as important that teams put in place their own procedures to eliminate problems when competition time comes up. A simple checklist to go over the above items can be used by a team member as the queue up for matches.

4

Interesting list.

In response to #18: Rather than wait for Vex to come out with a set of tools, can’t you simply buy some from your local hardware store that do what you want?

That’s what I did. I have never competed in a robot competition and only have the Vex kit for hobbyist use. I understand that you cannot use non-Vex parts in a competition, but is it against competition rules to use tools not supplied by Vex?

Curious.

I hope you get some of your ideas solved!

Cheers,
Mike

5

No, AFAIK there is no rule against non-vex tools. If so then a team could spend tons of money on new wrenches.

I use ball end hex screwdrivers from my work… they are awesome and I have yet to damage a screw with them.

6

With regard to #27, the reception issue: By the the quarterfinals, they had the crystal issue sorted out. Nonetheless, in our first (and only) QF match we expereinced a debilitating period lasting almost two minutes during which our robot was effectively dead.

I am the first to suspect “user-error” in these types of situations, but this robot was virtually unchanged from the state championships and had run many matches in that configuration. After the dead spell, the robot began working perfectly again; we hadn’t even taken it off the field (but had unplugged the tether during the match at the direction of the refs, which will allow this to happen). Even then, we did not request a rematch because I figured it was something in our robot. But after taking it back to the pits and running it there, we could find nothing wrong with it. To this day, it still works perfectly. Therefore, I believe–as inconvenient as this may be–that the VEX RF section needs imporvement.

With regard to #18, better tools: We did create our own set of tools. I just thought that it would be helpful if VexLabs supplied them directly. I really think that a nutdriver and allen wrenches with handles should be part of the starter kit. Those tools make Vex so much easier to work with that it might help make the early learning experience (when everything needs to be built twice) much more enjoyable.

7

Folks,

If you read carefully you will see that BillW did buy some tools from the local sources.

If you read his suggestion carefully and pat attention to the context you will see that he is suggesting that VexLabs supply a line of useful tools so that mentor/coach time can be spent working on a robot with a team instead of running around town discovering sources for useful tools.

Try not to frustrate folks by suggesting that they do what they have already done… :slight_smile:

Blake

8

No it is not. You are thinking too “narrowly”. Queued teams are not the only possible sources of RF interference. The answer is either carefully confirming that there are no background sources of interference and confirming that no one in the audience or anywhere else within range turns on a Transmitter tuned to the frequencies Vex uses (perhaps infeasible); or… using a different comm system that is very tolerant of other signals on those frequencies (perhaps feasible).

If RF interference was the source of any problems during any matches, it needs to be fixed; even if there are a thousand other potential sources of problems…

Blake

9

On number 27.

We too had huge problems with our robot not recieving signals, however it may not be the fault of the crystals. In 5/6 of our matches (2 rematches due to crystal error) we completely lost control of our robot. Our solution was to unplug and replug our tethers, which momentarily allowed control of our robot (like 5 seconds) before shutting off again. I think there was something wrong in the connection of the tethers of the championships to some remotes, because in the eliminations, we borrowed remotes from another team and it worked perfectly.

10

When I first read the opening post, I thought it was a bit too much. Then I realized some of the stuff is feasible, then I realized that most of what you are suggesting would take away from most of the learning experiences. For examples: 5, 6, 7, 8, 9, 14, and 22. Each of those suggestions can easily be done with trial/error or other methods of learning. A lot of this sounds like “easy” ways around problems which is anti-FIRST.

The tools really aren’t a big deal, you can feasibly use the provided tools until you find a very good set of tools that would work.

I agree, number 27 would really tick me off if I were in that situation.

I don’t think torx head fasteners would really be advantageous. They are hard to find in hardware stores and the tools are fairly expensive. The True Value store that I work at has nearly 2,000 different fasteners, but none are torx head machine screws. We also happen to be the largest fastener distribution store in Eastern Iowa. Also, most people wouldn’t know what torx head screws are and may get even more confused. Why not just make them 12-point or security screws then? I understand that they provide more torque ability, but really?

I don’t think any parts need to be pre-drilled or fabricated. A simple drill can fix this problem.

Sorry if I was a bit harsh, but there are a lot of demands that I don’t think IFI has the capability to match, yet. Implementation of these things may happen over several years.

11

those are some really good topics that should be emailed or somehow gotten to someone who can make some of those changes.:slight_smile:

12

All feedback posted on vexforum.com is taken with great consideration. I will be sure to bring these up at our next Vex “new products meeting.”
I am taking all suggestions very seriously. IFI is committed to the Vex platform, and it’s continuous improvement.

Regards,
John V-Neun

13

True, but my point was that it has become too easy for teams to blame interference as the cause for eratic behavior. The issue with some of the occurances was that it could not reasonably or conclusively be determined that interference was the cause. Making this determination is not easy to do after a match has been run and the damage has been done. We look for the obvious and most probable causes first based on the symptoms, and then work through them to the not so obvious. “Fixing” interference problems may or may not be easier than my take on it (remember I’m an ME not an EE guy), but in my view it is not an easy fix for some forms of interference short of redesigning the RF system used in the Vex kit.

Yes, there is a fix for the duplicate crystals used which is a procedural one that I am sure will be implemented in future competitions. I don’t believe we have to worry about that since I am sure FIRST has heard more than a mouthful about that issue. But what about matches where there were no duplicate crystals in the hands of eager teams? What about external sources such as equipment someone is using in the audience, or equipment that is being used by GA Dome staff, etc. Controlling internal (FVC) sources of interference once identified can and should be controlled. Again, it’s mostly a procedural issue with teams, robot inspectors, judges, etc (they all usually turn robots on at some point). But its those external sources that I worry about that may be hard to identify and control.

I tell my team and other teams attending the state competition to not bring any crystals to the event at all. They have no need for them since they are prohibited from using them, and the event managers provide the ones they need for competition.

I have thought about this since last year and want to hear some feedback from others on this. Can the crystal pairs go bad over a period of time? Can the spec on their frequency rate drift apart? Could we be looking at possibly defective crystals at worst or marginally useful ones at best? Is there a way to test them before putting them into use in matches? Most of the competition crystals get a lot of use since they are passed around to regional and State tournaments. There are still some unexplained problems that occur during matches and its my troubleshooting background talking here that wants to test for and evaluate possible causes. Outside of the Dome however, it gets difficult to try and recreate that environment and the conditions leading up those problems.

14

I’m glad to hear that. That’s why I will always buy from IFI FIRST (pun intended).

15

The RF interference could be a discussion topic all by itself if it isn’t already. I have had significant trouble with my bot and RF goofiness. For an FSK communications system, I am quite disappointed that the receiver is so sensitive to AM noise. As an experiment, touch the transmitter antenna to the robot chassis. On my robots, I get erratic behavior.

What I suspect is happening is the receiver is interpreting some false 1’s and 0’s when RF amplitude noise is introduced, and the microcontroller cannot differentiate those errors from valid user input.

This was a real frustration with my robot when different metal arm segments would “brush” up against other metal pieces. That always led to erratic behavior.

Anyway, this is still the best kit around and manages to keep sneaking into my piggy bank now and again. I just can’t stop creating new things with it!!

EJ

16

JJ,

Would you care to defend this assertion? I am referring to primarily to the “anti-FIRST” assertion; but the “‘easy’ ways around problems” puzzles me too.

Blake

17

First, I apologize for my extended absence.

I read with interest some of the above comments, and I have concluded that the priority of several of the items is reflective of one’s overall goals.

My primary objective is to give kids as much opportunity to experiment as possible. The kids I coach have limited amounts of time–I want them to use it creatively. Sure, it is great if they learn how to use a saw to cut down some stock and then burnish the edges, but after the first three or four times, they pretty much have this skill mastered. From that point forward, every part that they need to fabricate takes time away from that which could be used exploring new ideas. My kids are not likely to be machine shop operators; they very well may become aerospace engineers. Which would you rather have designing your jet: someone that understands mechanics or someone that knows how to drill 400 holes in a piece of tank tread?

Do most of the suggestions in the first section make it easier? If spending less time fabricating qualifies as “making it easier,” the answer is yes. I am OK with that.

A secondary reason is that I would like to be able to re-use as many parts as possible. If it is important to me from a budgetary standpoint, it is doubly important for school systems on tight budgets. I expect that many teachers would be reluctant to let a class full of students begin cutting up parts as kids think they need them. Most robots have some symmetry, but if half of the longer parts have had an inch or two cut off of them, it makes it that much more difficult to assemble the needed components. Keeping an eye on kids running power tools while teaching class also presents a logistical headache. Schools have classes that teach fabrication. Vex should be used in classes that teach mechanics and related topics.

I will concede that my desire for torx fasteners may be misplaced. Torx drivers are part of nearly every bit set, and we encounter them much more frequently that allen heads. If the rest of the world is still “allen-based,” however, then I am happy to go along. As noted, we have the necessary tools a this point; I just want others to have easy access to tools that will make it much easier to get started. Again, the faster kids can jump in and begin exploring, the better.

As for the second section regarding motor improvements etc: I still believe that most of these suggestions are valid–although improved motors would remove some of the design challenges and make it “easier.” They might also enable ideas that are simply not practical with the current system.

If nothing else, the servos and encoders need to be redesigned. As it stands, the encoders are far too large to be used in tight spaces, and the servos lack precision/torque which cannot be improved because of their limited range. In this case, I think designs are not being executed because there is no practical way to accomplish them within the VEX library of parts.

Bill Wiley
Coach, Vexy Things

18

We randomly lost control of our robot 10 seconds into the tele-operating period in a semi-finals match. It then continued to go back into our autonomus mode stripping our arm gears…lol

Explain that one.

The hex-ball screw drivers are amazing…allows you to tighten and loosen screws from multiple angles (around gears, wheels, and other metal).

I agree with the unreliable servo motors and upping the strength of the motors.

19

I certainly could have used a crimper with crimp-on connectors specifically for the Vex system. It would make it easier (or at least make it look nicer) to use custom parts, in addition to making custom length cables. I made a custom bumper with multiple tact switches and I made a very ugly connector to hook up to the microcontroller.

20

I had never noticed this post before, but I think BillW’s list was really good. It’s interesting to note how many of his suggestions are either in the product line or were shown at Worlds this year. This is what you get with smart customers and a responsive provider.

Now, John V-N, let’s talk about that custom PWM cable kit and the new servos… :slight_smile: