Re: What NEW Vex Accessories Would You Like TO See?
 

Hey Foobert!

Can we convince you to post more complete descriptions of some of your suggestions in the Homemade Parts thread of this forum? That seems like a good place for me to go looking when I am ready to do something like build the LED gizmo you distilled into a one-liner in this thread.

I think that creating a small library of that sort of design material would be a useful investment?

Blake
PS: If the library already exists somewhere, please just point me at it or put the pointer into a new (read-only) thread with a corresponding title.

Re: What NEW Vex Accessories Would You Like TO See?
 

Here are a few ideas I had..

- As someone mentioned before a way to lock the clutch to the motor and also a way to lock the shaft into the clutch

- Possibly a few different motors geared toward different applications, such as high torque low speed, low torque high speed, etc.

- Different brackets / different ways to mount motors & servos. From my expierence with the Vex kit I find the way the motor mounts kind of awkward in different applications. Different brackets that could attach to it would be helpful, or a few different holes on the motor itself for different mounting positions.

- New, Stronger Chain. I recently made a ball launcher with a 3500-4000rpm flywheel. Part of it was chain drive, key word was. When I got it up to full speed and accidently tapped the joystick backwards.. little was left of the chain =)

- As someone mentioned as well, a worm gear system for high torque applications such as arms, etc.

- Potentiometer. Yes I read you can buy one and modify it to fit your use, but I'd rather buy one I wouldn't have to rip apart.

- Keyed PWM extension cables. Readily avalible standard, but fit much nicer keyed.

That's all I can think of offhand right now, but Im sure I'll come up with more later.

Re: What NEW Vex Accessories Would You Like TO See?
 

I want to STRONGLY agree with the need for servo mounts that permit mounting the servo on a support in any of the 6 orientations (3 orthogonal axes) possible for the servo . Not being able to do this is constantly (in just about every machine/bot I build) ruining othewise good solutions to design problems.

I suspect a bracket(s) and/or clamp(s) separate from the servo is the right way to do this.

Mounts that are integrated into the servo will make the servo larger than it is now; and that will mean it will fit equally poorly in all orientations.

A separate bracket, that is used only when necessary, won't get clog up your designs in situations where the current servo plus its integrated mounts is good enough.

Re: What NEW Vex Accessories Would You Like TO See?
 

When I look up McMaster 2126T1 I find "Urethane Polyester Reinforced Core Belting 1/8" Od, Green". Is this supposed to be a replacement for the Tank Treads????

Did I misunderstand what the "email" was recommeding?

Blake

Re: What NEW Vex Accessories Would You Like TO See?
 

I'd like to see an angle sensor. The shaft encoder is close, but because it doesn't report direction there's no way to tell which way the shaft is turning.

Combining an angle sensor with a motor would be great -- I believe that's what the Mindstorm NXT is going to do, so that in addition to sending a command to turn on the motor at some speed, you can also have it rotate an axle some number of degrees. And you can use the motor to measure rotation.

Tac

Re: What NEW Vex Accessories Would You Like TO See?
 

New material for the Vex Tank tread. The plastic material is so slippery on most surfaces. I would love to see a rubber feet on the tank tread.

Re: What NEW Vex Accessories Would You Like TO See?
 

At http://www.vexlabs.com/forum/viewtopic.php?t=75 in the VexLABS fora, VexLABS gives their reasoning for using the material they chose. That doesn't mean that their crystal ball properly foresaw where the treads would see the most use by most customers; but it does explain why they chose the plastic (delrin?) that is used.

Blake
PS: EVERYONE - According to the folks who answer questions posed in the VexLABS fora, VexLABS does not monitor these Chief Delphi fora/threads. We need to devise a way to get our suggestions and requests from here and into the VexLABS fora. Is there a moderator who can become resopnsible for posting summaries on the VexLABS site?

Re: What NEW Vex Accessories Would You Like TO See?
 

OK - That is good. I was a bit suspicious that the answer I got at this URL http://www.vexlabs.com/forum/viewtopic.php?t=813 might have been the official party-line pravda rather than what was really happening behind the scenes.

Thanks John! You have renewed my desire to continue making suggestions here.

Blake

Re: What NEW Vex Accessories Would You Like TO See?
 

Longer sticks of the metal parts (like a 6' or 3' length of 1x2 C-Channel or a 3' length of the 5xN flat plates) so that the cost per inch that teams experience is lowered. Of course hacksaws and files or grinders/polishers would be needed by teams and hobbyists to cut these sticks into useable lengths with smooth ends.

A 1x5x35 C-hannel that had the same perforation pattern as the 1x2x35 C-Channel (so that the 1x5's weight would be lower).

Re: What NEW Vex Accessories Would You Like TO See?
 

In no particular order:

1) Shaft encoders that have quadrature outputs, which provides a way to know which direction the shaft is turning.

2) Screw-drive components like several lengths of screws and a easy to install block that will be pushed/pulled with the turning screw. It should also have an ability to slip if the block is stuck.

3) Gender-changers for using standard RC servos. It could just be a short, male to male adapter wire, or even a simple set of 3 pins that fit the RC servo's connector.

4) Vex output compatible Relay control module. It should have a LED on it to verify that its on. Just screw terminals would be fine for hookup. This would be good for high-current devices that can't be driven with the Vex controller or electrical system.

5) Wireless modules for PC to Vex control, debug and programming as well as Vex robot to Vex robot. Vex cluster bots will need this for sure, and the PC wireless would save a lot of time, and wear and tear on the wiring. It could be a proprietary module and protocol, or it could be something like bluetooth, or even infrared.

6) General-Purpose voltage measurement module with filter and pre-amp. This could be a small module that can take voltage measurements from any item, even if it's not within the controller's range of 0-5V. Just a couple of pots on it could set the desired low and high thresholds. If the input signal is very low-level, then a preamp could amplify it so the Vex controller could measure the device with maximum resolution and accuracy. A simple noise filter would not hurt either.

7) Robot kill switch for run-aways and debugging without servos moving. This could be a emergency stop button that locks into the "off" mode when pressed. It could look just like those red e-stop buttons found in industrial systems. This switch could also be used to disable the servos when the robot is on the bench.

8) Locking toggle or slide switches. These would just be on/off switches that lock into one state or the other. These could be used for debug, and for any program function checking for a digital input.

9) Longer screws in standard parts. Sometimes the long screws are too short for the application, that also includes the extra long ones in the track kit. About 50% longer should be enough.

10) Some kind of photo sensor for a variety of applications. It could be used as a photo-interrupter for making encoders and making non-contact limit switches. Perhaps a matching transmitter would work with the existing photo cell sensor. A infrared transmitter / receiver pair would work well too.

Re: What NEW Vex Accessories Would You Like TO See?
 

I would like to see some motors/servos with double shafts (front/back) and common mount points like hitec/futaba/etc. along with new brackets so we could do lynxmotion/robo-one type appendages.

Re: What NEW Vex Accessories Would You Like TO See?
 

The C language instead of Easy C standard would be nice. :p We'll have to teach the youngins how to code and then not apply it otherwise.

Re: What NEW Vex Accessories Would You Like TO See?
 

You can use any c compilier with the ifi loader and just use regular c. Easy c is not required even though it comes in the box.

Re: What NEW Vex Accessories Would You Like TO See?
 

My principal gripe with the Radio Shack sensors so far is that they are too wide-angled. I can't get useful performance from the light sensor or the line follower without a very tight sunshade. (LEGO uses a relative pinhole on its light sensor. VEX covers half the sky.) The ultrasonic sensor can detect an inch wide post at a reasonable distance, but it can't seem to detect a foot wide hole at more than about a foot of distance. The beam is too wide.

The VEX "line follower kit" uses infrared. LEGO uses visible light. VEX is harder to use because infrared reflectivity does not match visible light reflectivity, so picking line colors is a bit counterintuitive, and explaining it to the spectators even harder.

It would be nice to package two sensors in the "optical shaft encoder" so that I could detect direction of rotation. (So I can carefully bolt the two sensors in the kit together with a 2 degree skew, but that's iffy. Can't we do as well as the X axis on my mouseball?)

How about an analog angle sensor? A wide angle LED and sensor looking at a printed card should be able to report something like sine and cosine of rotation angle pretty cheaply.

Re: What NEW Vex Accessories Would You Like TO See?
 

I started with Mindstorms and there are a few things about the Vex that are inferior. 1) No start/stop button, the Vex will happily run off the table just because a new program was downloaded. 2) No way to maintain multiple programs on the Vex controller. This is *very* handy. 3) No LCD interface built into the controller. (I built the Palm Vex project at HobbyVex.org for just this purpose.) 4) The missing bevel gears etc mentioned earlier prevent a straightforward translation of many Mindstorms robots into Vex. 5) Screws and Nuts are very useful, but it would be wonderful to have some kind of quick connect/disconnect especially in hard-to-reach places. Imagine just snapping it all together in just a few minutes... 6) The kit doesn't come in a box that is very useful for holding all the parts while working on projects. 7) Only 1 starter project is provided with the kit, almost nothing is available elsewhere. 8) Although Vex interoperates with Erector Set/Meccano very well, the Lego parts are just not very compatible. It would be cool if there were some adapter parts that helped secure Lego parts to the Vex :-) Once a couple beams are attached you should be able to do anything.

Don't take this wrong, the Vex is great and has many advantages over Mindstorms (also mentioned previously in other threads.) Fixes to the things I mentioned above would simply make it unbeatable.