wannabeaflyers 6 DOF with 24V DC gearmotor

i did some research on wheelchair motors and they are worm gear motors. Pictures will help.

And this how typical.12v worm gearbox looks like

I hope this help

Cheers Tomkil192 Me Being Deaf Clicking Noises are'nt a Problem ( being deaf has its advantages soemtime, all i have to do is switch of my Cochlear implant and i wont hear Squat LOL ) i kept the breaks, so that's an option i'll be considering big time , refitting them sortta messes up the idea of putting an optical encoders on that motor shaft idea but where there's a will there's a way .. been looking for years for Cheapish Wormgear drives But they are still not hear at the prices we DIY guys want to pay ( Yeah i know tightwad, cheapskate comes to mind) ..

Hmmm did not see The Picture when i wrote that last post , I may well have to crack one of these babies open just to make sure, Maybe the Helix on the pinon has to be over a certain ratio before it will stop backdriving , i can definetly move my un-powered gearboxes by hand with a bit of force so that may well be a saturday lookie see job

Thats why they have the break. Any geared motor without "hold break" will move under heavy load.

Not true wormgear motors with big reductions are fully locking.Tooth angle does that with big reductions!

ok. thanks for correcting. i agree that motors with big reductions and correct tooth angle will self-lock.
you loosing the speed but gaining troque and self lock.

Hi Guys Just got and answer from the guys at Dimension engineering regarding the max brake operating frequency , apparently the Controller can handle brake switching at the rate of 1 millisecond , I need to figure out what this speed means with regards to the motion position demand output which I suspect will be less than that , this weekend I intend to fit the brakes to me test setup and will let you guys know how it goes , They did mention something about configuring the outputs direct so , more manual reading again cos im sure I;ve missed that section .Cheers Crew

, I have put Swiveling suppoert plates under each unpowered actuator so I can lock any actuator arm in place and as you mentioned this allows me to fix them in place during autotune, been playing to today sun or no sun lol in the man cave and some positive news . that when the actuators are powered up and in Describe live test mode, they can easily lift my big butt and platform and chuck it around with ease and seem to draw max 10amp if that per actuator when doing so , that being the case when all 6 are sharing the load im hoping for even better results . as soon as the motor is un powered then yep she will back drive every time , im of the opinion that if I can get the brakes fitted then the kangaroo may well do the job as they switch the brakes off when a position demand is sent . All in all im very pleased with this setup and other than beefing all the actuator rods and Rose joints up,( they are 8mm need to be 12-16mm or bigger) the mechanical aspect seems satisfactory considering its my first attempt , will spend this weekend re-housing the electronics into a dedicated enclosure and fit the brakes to one set of actuators to see if that cures the unpowered back-driving issue.. I Think that if this can be cracked then this will be a great step forward for reasonably compact seat mover 6 DOF Systems .. From the test above I don't think im even close to stressing the 6 gearboxes/motors with my weight and bare platform so keep watching this space

I just bought 4 wheelchair motors for bargain so im looking foward how you will deal with the break option.
good luck . you might need seperate supply for breaks. I tryed to operate the motor and break connected to one 700w psu and fail... They just arrived so i didnt have time to play with.

Hi Tomkil192 , I have not used my 24v 55 amp psu yet but with the car batteries, in the past I found that once you id the brake leadwires and connect them to the + v and 0 battery neg in parallel with the motor leads then the motor spins freely becuase the brake are engegised and therefore released. You already knew that so sorry if im repeating stuff you already know as I said not tried my psu yet so thats another test I the making glad to hear you got them at a good price, nothingis wasted lol if not for this project they will do for the next.. one thing i found out was they will chuck a seatmover around nicely as I think with the racing sims there are fewer power off moments , that may mean backdriving wont be an issue For race sims
..

OK Guys latest test , Refitted the original electric brake to one motor / actuator setup Connected system to Describe and Set The Brake function ON for the Sabertooth 2 x 32 , Then uploaded the new settings and Redid the Auto tune .. I first checked that the reassembled Brake still worked as it should ( Box Ticked OK) electrically and mechanically ( Box ticked LOL ) then I powered up the Sabertooth setup and observed that with no position demand signal sent ( i.e Idle Mode ) then the brake was Engaged ( Ov in brake circuit the default Condition)and I could not physically move the actuator arm where previously I could back drive it with one hand , I then selected live test in Describe ( the brake was still Engaged All good so far) when I moved the cursor in the live test Screen ( sent the position demand request) the Brake went to 24VDC ( disengaged ) and the motor was able to Move through the range selected and atfollowed the cursor position at the quick changing position I could achieve using the Cursor mode ( Ohhhhhhhh now this was good stuff LOL ) she seemed to handle everything I threw at it with 2 lead acid batteries hanging of the actuator for loading ... once I exited the Describe live test the Brakes went to 0V and Locked the Motor shaft as expected. this called for a "Yeeeee Haaaaa baby" Moment .... I repeated this test several times in each case trying to load the actuator as much as possible and result seemed consistent , The only observation was that the Brake solenoid seemed to get warm ( This I take it is to be expected as these were never meant to be switched a the frequency im chucking at it).. ..anyone with any thought on this will be welcome . based on this test I'm gonna take the plunge and order 2 more 2 x 32 controller as the 2 x 25 does not have this function .. still Not had a chance to try the optical encoders yet, but that's another test waiting in the wings .. Oppps Forgot to say ran this test with BFF software and FSX and again it seemed to do the job ( early days yet but I'm thinking , getting closer to the final goal ) Car racing sim may be too much for the brake switching idea , but as mentioned in earlier post there may not be the same back-driving issue.. Hang in there guys , more to come

some pics of the brake assy & 1st stage of test mockup

Got some Potentiially Good info from Ian At BFF and I may have be looking at the wrong area regarding my backdriving Issue Ian mentioned in a request for tech info "but when the system is in operation they would never be unpowered - they should always be trying to hold position." Hmmmm That what I thought was supposed to happen, but the fact that every now and then one actuator would seem to lose power made me think this was a mechanical issue... Now im wondering if all my problems are due to not Fully loading the Platform with enough weight during Autotune,,,,

You Guys have stressed this before the platform need to be fully loaded , But as I have designed that part of the project as yet ( just was going to mount a seat for this stage ) I thought I could get way with easing up on the load.... so me thinks Bags Of sand time once the actuator rods have been beefed Up and bigger rose Joints fitted ...The Shaking that Autotune does is Scary LOL hence the shortcut But That may well be the answer in this case ,
So I'm thinking ( maybe wrong again :-( ) that a Weighted system would load the Actuator arms motor and in turn create better feedback Due to the sensor picking up the slightest movement and so altering the position and the PID would kick in to maintain position without losing motor power.. OK this will Mean some Down time while I Upgrade bits but i'll be back LOL good thing about all this is that I learn a wee bit more about the software and mechanical interaction with each SELF Inflicted Problem May not need the Electric Brakes After all But as with all things in Wannabeaflyers world its Suck it and See Time

Done it again As soon as these bugs are sorted I'll place all the Drawings , Circuit layouts and Assembly Notes here on X-simulator free to be Changed , Hacked and Downright improved upon for any user who so wishes as a way of saying thanks Guys

1 millisecond switching is plenty fast enough I think since a brake is an electro-mechanical device.

The more time the brakes are on (disengaged) the more heat generated. The frequency in and of itself is irrelevant. They will generate the most heat when they are on constantly. If your motors are not rated for continuous operation though changes are the brakes aren’t either. If they get very hot for long enough I have found that they can start dragging. Btw, not only do brakes heat due to the solenoid, but if they are attached to the armature of the motor, they also act as a heat sink for the armature which can get extremely hot.

Ideally, the only time you want to use brakes is to hold your rig at a particular position when it is not in actual use and powered off. This is how I used my brakes but after some use the heat from them being constantly on most of the time caused deformation of the metal brake disk and dragging so I remove mine entirely now.

This is looking good! Nice pics

Hi BlazingH Once again your on the money, In Light of the Info i got from Ian i have been rethinking my problem and leaning more towards beefing up the platform so i can safely Do redo the auto-tune again and some decent load testing .. may take a week or so while i rejig stuff but i'll be back with more info after that , Would be great to not need to fit the Brakes at all so concept prover build V2 Updates are underway, Hey shout out to Silentchill can you give me an idea of the size of the Actuator Rods you used on you 6DOF sime Please : -)

Hi Guys Immmmmm Baaaack .. Ok "Ding Ding" Bell sound gentlemen its Round 2. Finally reconfigured and beefed up the MK1 version , no major changes (I have quickly learnt you'll be forever tweaking designs in that case) I now have 3 2x32 Sabertooth Controllers Linked in my system ,
All systems seemingly working at basic level, and the Platform has been beefed up , new 12mm Threaded Rod and M12 rose Joints( Hiem joints to our American Cousins) fitted,and new controller enclosure + another lesson learnt was don't underestimate the power of these gearboxes i inadvertently managed to bend one of these 12mm rods during autotune ( forgot to wipe the original settings doohh so take care when testing these systems guys) and done a Complete Dimension Engineering Kangaroo Retune of all 6 Actuators this time with 75KG load on the platform ..

Scariest time was Autotuning platform with 75kg's on board ,I mean scary , that process really bounces the platform around . good news is that it seems fine afterwards , so today some basic system trials commence again..

had major delay with FS2004 software as I upgraded my fully working laptop to windows 10 , and blow me , now all of a sudden fs2004 wont work , wont start, does zip when trying to run . to say pissed off was understatement , several internet fixes tried , at least 7 program removals & re-installs and still dead , Not a happy chappy . I used the laptop because its easier to develop stuff in the man cave ( not ready to stick the Tower PC out there ) .. anyways I loaded FSX 10 to the laptop yesterday so at least I can get back to testing the Platform
Movements ...

Attached a few pic of the rebuild and will stick the build info once im happy that it "Does what it say on the tin " LOL

Arrrrghhhh argghhhh ( cant find smiley for Pulling hair out of already bald head) im almost at give up Time with these Kangaroo Controllers , its been a 2 week battle to get a decent set of auto-tuning done and its still not where it needs to be for Reliable repeatable operation , Gonna hang in there for one more Blitz and if its not Good then im gonna have to rethink the Control Scheme on my 6 DOF Platform ,
On the face of it it should be easy ( well for normal guys anyways) straight forward , Connect kangeroo to brand new 2x32 Controllers , Connect Hall effect Position sensor , Set Dip switches on Both Kangaroo and Sabertooth Controllers , Connect Motor/ Gearboxes , Place test load 80KG in race seat on platform , Supply 24Vdc to power system , Connect USB - Serial adapter to PC, Run Describe Live test and select Auto tune Option , Move Actuator Arm to Max sensor range ( 4.4Vdc ) Move Actuator arm to Min sensor range ( 0.3Vdc), Return Actuator arm to Midpoint ( 2.5Vdc) and hit Continue, Watch system beat it self to death in the name of Auto-tuning . Hold breath if it survives ,, ( swear like Buggery if it reports Control ERROR and kick something Soft ( tried hard stuff it hurts) , Start again with fingers crossed( now reports cant move motor) Grrrrrrrrr Grrrrrrrr and More F@##ing Grrrrrr.

i know the old saying a bad workman always blames his tool But For ( expletive entered here) how hard should this be or actually why is it this hard LOL

Good news is the Platform and seat are still in one piece, so im taking that as a good thing , the other positive a=is that the motor/Gearboxes seem up to the Job and current drawn so far is nowhere near the levels i thought they would be,Oh

I also found out that Server PSU are Noisy Bugger, I actually had to take my hearing aid out the dammm things were so noisy. today is the 1st day that i used them since i modifed them as 2 x12 Vdc 52 amp units connected in series. least they work As well ,,