K8055 - Dual Wiper Motor Control with Variable Speed

Tim,
Have you thoght how you plan to attach an actuator arm using the chain?

TTim,
Update on my progress or lack thereof. Downloaded the demo software from Velleman and did a quick wiring job on the Victor 883 speed control. Found a 24VAC transformer in the work van and a 24VDC power supply off a shelf in my office, hooked it up and the ESC blinked at me, looked that up and no PWM signal was the error message from the manufacturer.

Indication: Flashing ORANGE indicator on power up.
Problem: No PWM signal.
Possible Solutions:
1. Ensure the transmitter and receiver are powered ON.
2. The PWM cable may be improperly connected.
Check wire color-coding at each end. Check that
the connector is not off a pin at the receiver end.
3. Check for a good PWM signal by connecting a
known good servo to the PWM extension cable. If
the servo does not move, this can indicate either:
a) a faulty receiver
b) an improperly connected cable
c) a bad PWM extension cable
Note: The servo requires that 5V be present on the
center pin of the PWM cable. This connection is not
required for the Victor.

I may just try out the relays. If I have a huge desire to get really crafty, perhaps I will take the old robot controls and hook them up to the PC. Now there comes some programming I will never understand hahaha.

Hi Shannonb1

Yes I have - and you have already seen it being sucessfully tested in prototype! 8)

The method I will use is simplicity itself - which is really important for my build as I'm trying to keep it possible for complete beginners!!
I simply have a wooden arm, and use screws between the links in the chains:



This method can definitely take the forces involved - the picture above shows the prototype that I used in the rocking couch stress test which went way beyond any stresses that will be experienced in a ballanced platform!
(here it is again for anyone joining the thread at this point):

http://www.youtube.com/watch?v=grfrH1DTS20

It is also extremely easy to disassemble for maintenance such as replacing or tensioning the chain.

Tim

@supermodfan

Welcome aboard! - Thats a long list of possibilities you have there...

...I'm prepared to bet a few things though:

• Firstly, that the K8055 is not working as you expect only because you are expecting it to do something different from its designed function - I get this feeling from your comment in point 3 about looking for a good signal - The K8055 does not give an output signal as such...

• Secondly, that the controller you have is designed to be tied in with a R/C controller...
Actually, on that point, Tronics AMC board may be more what you are looking for... I may be wrong, but I believe from my early investigation of the design that this can be used for R/C servos - you may be able to simply connect your board directly to it (someone keep me right here please!! ) - If so, that is definitely your best option with the hardware you already have!!

• And thirdly, that the solution isn't in the list at all!! - it's never that easy!

Lets start with the basics - the relay board might be a good starter for you as it is so simple (only 6 components even if you use a socket for the relay) and cheap! (less than £10 even at maplin prices!)

In post 9 on page 14 there is a description of how the relay solution works... understanding that should be your starting point - the operation of the K8055 is such that the output channels dont actually output - instead, they take current in when opened (activated) and it is this change in current which can be used to control a circuit.

There is a description of how PWM works in there too (though it is basic) - again, this is useful knowledge

If you are experienced with electronics this may be an unnecessary step, but I would suggest building a 12V relay circuit first to get a handle on the controls and the limitations of the board... you may have problems if you leap straight in at 24V as there are safe limits on voltage and current into the K8055 outputs... and it is not always the case that 24V motors are more powerful anyway! (This depends more on what they are designed for).

After that, read this thread from end to end looking for video demos, circuit diagrams and discussions on designs and principles - there has been some superb contributions from guys with way more experience than me, and this might help you - it has certainly helped me!!

There is a complete breakdown in bits through the thread so far of how to set up the K8055 itself for both controlling the motor, and also for feeding back data from a position indicating device like a pot - also of different off the shelf hardware options contributed by adbgg, riton and nima for options of hardware that you can drive with a K8055... much use has been made of the experts on the Velleman forum - hence my earlier suggestion to post there

and of course, if you get stuck, are looking for inspiration or have some weird stuff happening, just post!

Tim

Tim,
Wow this is so much fun. I haven't built circuits since school... over 10 years ago when I went back that is... but this worked perfectly. I threw it together on a Radio Shack breadboard using a 12 VDC wall wart. (Plug in 1 amp transformer) I could only find a quad relay in my work van and while I was looking through my old stuff I found the little ESCAP 22VCD motor for testing. I believe the motors were for a 3 lb robot idea. I think I am well on my way to building a motion simulator platform. I am thinking about building a miniature platform for testing...



It is a real mess but it works hahaha...

will the velleman 8055 work with 3 motors for a 3dof simulator?

Not being too well versed with the 8055 I know that there are only 2 PWM outputs, however the software, at least the testing software, allows four board addresses. I would think that with 2 Vellemans you would be able to do 3DOF however keep watching this topic. There is ALOT of information presented in quite easy to follow terms, and Tim has done an amazing job documenting progress! I think that is what is attempting to be done here... 3DOF... I myself just want to do a simple 2DOF Knuckle under seat type of project.

Hey Tim, i know the motor can handle, chain can but my concern was for the wooden arm, I would us a rod welded or some steel with bolts through the chain....am i thinking about that right? your design, just something I thought about knowing how wood can break

I'm not worried - yes wood can break, but plywood is stronger. This is because the thin layers of wood (or plys) are arranged so that the direction of the grain alternates with each layer. This means that there are far fewer weakness between the fibres of the wood that can be exposed.

I am 6'11'' (about 210cm) and about 17stone (114Kg)... I can stand on the middle of a 25mmx18mm square strip of plywood held up on two blocks with no problems... it could bend, but it wont break! :lol:



The bending wont happen in the build anyway as most of the load is compression along the grain, and this is where wood is at its strongest (think of the force acting on the trunk of a tall tree).

If you want to use metal - and that is a fine idea and probably better (but more expensive and less convenient),
I would go with bolts through the arm rather than trying to weld chain onto a bar...
Welding could weaken the chain and would never be a satisfactory join... and difficult to maintain

The forces involved in lifting that sofa are way more than you would experience in a build with a ballanced platform - and half of the actuator housing was missing so that you could see what was going on! - I wouldn't worry about it

Tim

You can only drive 2 motors with 1 x K8055 (there is only 2xPWM out and 2XInput for position control)

In theory you can have as many as 4 x K8055 connected to one instance of X-sim
The card features a jumper array that allows you to set up to 4 card addresses of 0,1,2 and 3.
(See page 11 Post 1)

I have had consistant success with driving two motors from one board, so I know the PC can handle the data calculations...
BUT
When I tried to run two motors using two separate K8055s with one on each, I had problems and the second card crashed.

It has always been my intention to get a 3dof sim built - or a 2dof with an additional motor set to simulate traction loss.
At the moment, this may have to be by using two networked laptops as slaves to control the simulator in addition to the networked gaming machine - not what I had hoped for based on the cost alone.

When I have further data I will post a far more detailed report in the bugs and glitches section

In the mean time, I am happy to work towards a 2dof actuator controlled version of the test rig I put together before:

http://www.youtube.com/watch?v=nO-NaX_00I0

Tim

You can only drive 2 motors with 1 x K8055 (there is only 2xPWM out and 2XInput for position control)

In theory you can have as many as 4 x K8055 connected to one instance of X-sim
The card features a jumper array that allows you to set up to 4 card addresses of 0,1,2 and 3.
(See page 11 Post 1)

I have had consistant success with driving two motors from one board, so I know the PC can handle the data calculations...
BUT
When I tried to run two motors using two separate K8055s with one on each, I had problems and the second card crashed.

It has always been my intention to get a 3dof sim built - or a 2dof with an additional motor set to simulate traction loss.
At the moment, this may have to be by using two networked laptops as slaves to control the simulator in addition to the networked gaming machine - not what I had hoped for based on the cost alone.

When I have further data I will post a far more detailed report in the bugs and glitches section

In the mean time, I am happy to work towards a 2dof actuator controlled version of the test rig I put together before:

http://www.youtube.com/watch?v=nO-NaX_00I0

Tim

hi Tim and thanks for the reply

think i will give it a try on a simple 2dof for now on a prototype rig could i be cheeky and ask you to email me the plans for your motor driver circuits

many thanks

Andy

I think they are in the beginning of the post, if not search on his posts, he also has videos on the relays that he uses.

Hi Andsolo21 - ShannonB1 is right!

Page 2, post 8 for the basic design and construction notes
Page 14 post 9 for a description of how it works, and my suggestion for how the design could be upgraded for 24V

There is now so much of this thread that I am going to edit the first post and put an index in that references the key useful bits including plans, video tutorials and design considerations... will be on this weekend

Regards

Tim

Hi there all and bigtalltim. Did you complete a 2dof sim with the K8055? I may have missed it in the posts. I am building a 2dof wiper motor job myself and am trying to find a circuit from start to finish of a K8055 - relay - motor connection set up. As I said, I may have missed it in the posts. I have the K8055RevMotor01 picture. But I am trying to make sense of the diagram PMW1 - (pulse width modulation) what is this from?Via a potentiometer?
Gnd - this I know, Any digital output - an output from the K8055? I thought you may need an analogue output.
just trying to get my head around this, and besides, the local supplier is out of stock of K8055's.
Thanks in advance for all your help and support.
Regards, David.

Hi Tim, you are an inspiration to all, i started making Thanos AVR controller etc some time ago, am guessing its about 85% built but i couldnt find all the components and as a result lost interest in finishing it. I started reading your thread and its re-ignited my interest in building a simple 2DOF or 3DOF platform purely for flight sim games. Im on a limited budget as the wife will kick my head in if i spend lots of cash so your solution is very interesting. I have managed to buy a new pre-built K8055 off ebay for £20 already. I have read all the posts 1-20 but im a little unsure of the parts i need, is it possible to do a parts list for a 12v solution with the full details of each component as im a complete noob at electronics. I have a maplins near me and will be getting everything from there.
Thanks in advance for any help, and keep up your excellent work.

2 1k ohm resistors,
2 tramsistors, I used 2N3055 can transistors,
4 diodes, 1N4001 should do
2 relays, 12 volt dpdt
Some form of a 12 volt power supply

That's it, remarkably simple!!!

where would one get that type of relay?

Fantastic, thanks a ton and a half dude! That helps my messed up brain!

built this too and no way compares to pololu to slow only drive my winchs at about 1/2 their speed plus gets alot warmer than the pololu so gunna try franks mosfet circuit but i think i will keep me pololu 12v12s till i build the courage to attempt the AMC.

But all said good idea to get the basic understanding on how it all works.