Futaba 6ex FASST

Morning,

Has anyone had any experience with the Futaba 6ex FASST 2.4GHz system? I was wondering what it was like compared to the Spektrum.

Cheers, Dave

i belive they dont fail safe on all chans only 1 chan so spektrum may be better unless theres been an update

(Message edited by jct on February 07, 2008)

Having compared field results with other 2.4GHz systems with people from the club i fly with, Ive come to this conclusion.

Failsafing as John already pointed out is only on the first channel (aka throttle cut). De rest of the channels stay in position until the signal comes back.

That is not acceptable to us because that means if the robot goes into failsafe during a right turn for instance, it keeps turning to the right instead of stopping.

The Futaba use a different way of avoiding clashes of the radios then Spektrums do. Spektrum uses something called DSSS (direct-sequence spread spectrum), and Futaba something call FHSS (Frequency-hopping spread spectrum). Futaba has dubbed this system FASST (Futaba Advanced Spread Spectrum Technology). Hows that for marketing. :)

Both are perfectly good methods of avoiding collisions, by most of the experts it is the general consensus the FHSS way is better because you never stay on a channel long enough to interfere with other.

Overall, if the Futaba receivers were to be made like the BR6000, with a programmable failsafe on all channels, the FASST would be the better choice. However, since this is not yet the case, and trust me, I always keep an eye out for these developments, we are down to 2 choices:

Graupner/IFS (Also know as Extreme power systems), or Spektrum DSM.

Both have receivers with programmable failsafes, unfortunately Spektrum does not have a DSM2 RX with programmable failsafe settings on all channels yet.

In the near future, Spektrum is going to release the DX6i, a new 6 channel transmitter that is DSM2 and DSM (like the BR6000) compatible, but way cheaper than the DX6 or 7.

XPS or Graupner/IFS is also an option, but very recently a problem was found that the modules do not hop to a different channel if interference kicks in. That means it will failsafe and wont return to work until the interference is sorted.

http://www.rcgroups.com/forums/showthread.php?t=814276http://www.rcgroups.com/forums/showthread.php?t=814276

For robotics, Spektrum atm is the best choice. For aircraft/helicopters, FASST would be my choice.

btw, there are more 2.4GHz players in the field like ASSAN and Nomadio.

The one I am watching with great interest although I dont like the companies boss that much is ACT Europe.

http://www.acteurope.de/html/_s3d-system_2_4ghz_.htmlhttp://www.acteurope.de/html/_s3d-system_2_4ghz_.html

The main advantage to their system is you can use your old frequency equipment alongside the new. so if you want to send with 40MHz you still can.

Technically you could use the futaba system if you had the throttle channel linked to a a large relay (solid state or otherwise) which cut out all electrical power on signal loss. Not an ideal solution though.

I hope futaba do sort out a system that failsafes on all channels. The annoying thing is that it probably isnt that difficult for them to do.

Gary - Not an ideal solution though I would disagree, M2 has always had a dedicated failsafe channel linked to power relays which removed power to all drives and weapon circuits. Thus the Futaba set is ideal and offers greater security in my opinion especially when you have popped FETs on a speedo sending a bot out of control. Also great for doing a power down reset to your speedo when it locks up i.e. Vantec and Roboteq.

Also whilst I agree it would be nice to have the failsafe feature on all channels, you could ask why should they give it consideration for a market that represents such a small percentage of their customer base. Implementing failsafe properly to all channels takes a lot of processing time when compared to a single channel so I would guess (no idea if Im right though) its not practical for this particular receiver.

Paul, not that many relais can shut down a robot on full pelt. Not without suffering any damage.

Combine that fact with the fail safe function, and you have a recepy for another power on led discusion.

Project One and II had the same failsafe setup, but used the 1 kg heavy Albright SW8024V b for main cut off.
The pricetag and the weight are prohibitive for a thoroughbread heavy.

Robbe Futaba has started a mass recall of ALL their Robbe T6EXP/FF7/TM7 and FASST modules. So far Ive only found the text in German, but The English version will follow suit.

Small mistake, TM7 is the FASST module.

Mario,

I have used the same cheap automotive relays since 2001 without a problem. Maybe they have seen a long life because M2 did not failsafe that often but more importantly, the relays break under load rather than make under load. A more recent development was to delay the failsafe relay for a couple of seconds to allow time for the speedo failsafes to operate where possible.

No intention of starting a power on light debate, just coming back with a different view on that of Garys post.

Leo, see http://www.technobots.co.uk/discus/messages/7/383.html?1202494298http://www.technobots.co.uk/discus/m...tml?1202494298 See last post on thread.

Paul, I may consider getting a 2.4gig futaba then :)

Hi Gary, I remain puzzled why some users have found problems with these 2.4GHz sets (and Spectrums) when used with some electronic interfaces / speedos. See Terrys posts on the same thread I linked to above. I have not been able to replicate any of the problems reported but thought I would mention it as it appears limited to robot applications.

paul

whens M2 coming back to fight :)

Paul, its not just robots... Ants trucks have a multifunction unit that doesnt work properly when running from an AR6000. Works fine with standard radio. Apparently the 6EX works fine too.

never say never but I no longer have any plans to return to the arena so I will not be able to prove that M2XT has the best flipper with its remote control variable pressure system of 10 to 50 bar :sad:

Hi Kane, any idea why because surely the receiver pulse output is not dependant on the carrier frequency?

im sure you can prove that when its back on TV

i have faith that its going to come back ! :)

The 3 main problems we have with the spectrums are the default neutral is not 1.5mS. Can easily be adjusted using the trims.
They dont seem to work when really cold, Solved by moving them away from the CO2 stuff.
The pulses are only upto 3.3 volts, less if external circuit pulls more current. Solved by Resistor changes in mixer board to drive the Opto-Isolators correctly. Bear in mind that most new receivers (including 40MHz) are 3.3V and it really depends on whats attached to weather they will work and even after saying that they are only minor problems and the advantages of 2.4GHz outway them for use.

Must admit I did like Pauls idea when I first saw M2 of the remote Isolation, does improve safety alot.

I have no idea unfortunatley... I dont have the equipment to play with it :sad:

Mark, voltage levels now that would explain it. Ill put a set on the scope tomorrow. I do recall a number of issues with driving interfaces with opto isolation some years ago which was solved by putting a failsafe inbetween to use it as a buffer / driver. The Ian Swann interface has opto isolation and would explain Terry Miles problems.

I always felt fair safer with the power relays and it also came in handy for S7 when I had to do a power down reset twice to reset a locked up Roboteq in the fight against Atomic - still lost though.

Mark, you are quite right, the more modern receivers only give out about 3V. Also the later failafes such as the Ripmax Extra only give out 3V. The old faithful FS-1 can be used to boost the 3V signal to 4.8V so these could be used with older interfaces (most likley incorporating opto isolation) that do not work with 3V signals.

Hello everyone
I have the new 2.4 fasst and the old t6exa
the later i have never had any problems with (except more and more interference)
After trying lots of tips etc I found the fasst will not work with old style interfaces
it has now been tested with a watty speed
controller and they work perfectly, but there
is only failsafe on the 1 channel,
the t6exa went into failsafe on all channels.
I am a bit stuck what to do now I dont really
want to add relays etc from channel 1 to remote
cut the robot,
unfortunately channel is the one i use for throttle on the left stick so I would have to
learn a different driving style, unless i can
change the transmitter around inside.
I have also wondered if it is possible to use a normal failsafe 10 amp relay connected to channel 1 so when this goes into failsafe
it cuts the pulses from the reciever to the speed controll/weapons etc on theother channels ?

The only solution I can think off is to swap the pot leads over inside the transmitter thus putting the failsafe on a spare channel.

Id then go the RC switch and remote relay route off of this spare channel and use it to cut all mains battery power....remembering to still leave the BEC or RC battery connected.

A bit of info that might help on the combatability issues.

Futuba in their think tank decided to make the servo pulse voltage 2.76v. Now this is fine if you just use Futuba servos. But most other servos are designed to operate at from 3 to 5 volts on their servo pluse voltage.

So the Futaba FASST seems to have the same voltage issues as the Spektrum...scroll up the thread for the possible FS1 Failsafe solution.

It also outputs a different pulse range to std.

I set the End Points on channel 1 (my test channel) to 140%
Then I measured the pulse using the HiTec programmer:
945 - 1521 - 2096

Normally we expect something close to:
900 - 1500 - 2100

(Message edited by woody on March 11, 2008)

I have now used the futaba 2.4 ghz fasst
at burgess hill,
I have chanell 3 (failsafe) connected to remote
kill on wy watty and also a battle switch,
therefor when i loose tx signal the rx turns off
the watty and my battle switch.
I have then got a 2nd battle switch connected to
chanell 6 for my flipper
(the solonoid supply runs through both battleswitches) so if 1 of them is off then my
solonoid is closed.
This all worked perfectly,
no interference to the battleswitches, and also
no large relay systems
power for receiver and battleswitches is taken
from the watty.

Terry.

Oh and I have also got my receiver in a little
metal box (rf) as im not taking any chances,
and my 2 antennas are taped at 90 degrees to each
other on a plastic case, this did make a difference there was some twitching when they werent at 90 degrees.

Terry.

I have just got one of the new Futaba 10C 2.4 GHz sets. 10 Channels, with settable (in the transmitter menus) failsafe on the first 8 channels.
http://2.4gigahertz.com/systems/futk9250.htmlhttp://2.4gigahertz.com/systems/futk9250.html

Not quite as flexible as my 9z (e.g. no easy stick-channel assignment), but nice.

For info, the pulse output on the receivers is unusual on these (apart from being only 2.8 Volts and with a frame rate of 72 Hz):

The pulses on the first six channels are all sent simultaneously. This is for the benefit of the helicopter boys - ensusures that multi-servo swashplates move straight up and down with no swimming.

The pulses for channels 7,8 and 9 then are also simutaneously, 3ms after the first group (rising edge to rising edge is 3ms). 10 is then another 3ms behind.

Our Wotty for some reason wouldnt work properly when connected to channels 1 and 3 in the usual manner. But works fine on channels 7 and 8. Not sure why yet.

John

John,
Ive looked at the 10c sets and they look an awsome bit of kit, will be interested to see how you get on with setting up etc.
Does your battle switch weapon rf relay work ok on the pulse rates ?
Terry.

I have built my own switch, which works fine with the 72 Hz pules put out by the receiver.

Found out that with the Wotty needs to have the enable channel connected to a different group of channels than the steering and throttle. So Channel 1 for steering, Channel 2 or 3 for throttle and channel 7 for enable works fine.

Very nice to setup with English words for all the menu items, rather than TLAs. Ive set it up with different steering rates (including exponential) for the steering on a three-position switch, and different rates for the gyro, also three position.

Used it at the champs - worked perfectly.