• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

JoyStick Wiring Help

Status
Not open for further replies.

twinforced

New Member
I have a Penney & Giles JC 200 JoyStick that I want to hook up to a speed controller from AmpFlow.

The joystick has 5 wires.

Red ..... positive voltage supply.
Black.... Zero voltage supply.
Blue..... X-axis output voltage signal
Yellow.. Y-axis output voltage signal
Green.. Center Tap.

Now what do I do with the Center Tap.

I'm new to all this so thank you for any help you give, I dont want to burn up nice new electronics the first go around.
 

justDIY

Active Member
looks like the center tap is a voltage divider, that you can sample to make sure the joystick is receiving the proper amount of voltage

Centre tap
A centre tapping is provided as a means of verifying the integrity of the supply voltage at the joystick. Clearly a high resistance or open circuit in either the +ve supply or V connections will affect the joystick outputs. The normal output at the centre tap connection is 49.16% to 50.84% of the supply voltage. A centre tap output outside this range indicates a fault in the supply to the joystick.
as far as what to do with it? you could hook it to a comparator, which would put your speed controller into shutdown if the CT voltage reads too high or too low.

or just leave it disconnected.
 

twinforced

New Member
Thank you, just leave it disconected.

I just need basic TANK control by use of the joystick.

Now I know the Blue and Yellow are for the X & Y axis.

It may be a very stupid question but I do hook up the Red to the 5v positive and the Black to the Controller ground ?

And one more Q..... Its called an Inductive JoyStick. What does this mean to me at try'n to use it with an AmpFlow Controller ?
 
Last edited:

justDIY

Active Member
I don't think you can just plug one into the other and have it work.

the controller expects 0 to 5v analog control voltage, 0 being stop, 5 being full-on

notice on the datasheet, they mention "Output signals should be referenced to the center tap voltage". So this means you'll have -2.5v full left (for example) and 2.5v full right.

sorry, this is over my head - perhaps someone more experienced with robotics can chime in.
 

dknguyen

Well-Known Member
Most Helpful Member
For basic tank control you need a mixer. Since you need to control two channels (on the motor driver) using a forward and turn signal. You can only control it directly if you start out with separate left motor and right motor signals...

unless you intend on having forward-backwards be CC/CCW for one motor, and left-right be CW/CCW for the other motor.


That said, the motor driver does say it accepts potentiometer joysticks which yours sounds like it is, so the motor driver probably already has mixing in it. I think the center tap is so whatever receives the joystick input knows what "center" is, relative to the X-Y voltage outputs. Center being Vsupply/2 (this is the centertap that justDIY is referring to, except he is centering it around zero when it's going to be centered around 2.5V) due to the potentiometer forming a voltage divider inside the joystick.

Go to www.roboteq.com and look at their user guide to verify the controller has built-in mixing. It should be analogous to the AmpFlow controller since they are made by the same company (except AmpFlow is meant for BattleBots). Do you really need the full 180A current capacity of the ampflow controller? What are you building? A battlebot. If you don't, you could probably save some money by getting an original Roboteq controller.
 
Last edited:

twinforced

New Member
Yes they have mixing of the channels.

They say it needs 5v for full forward and 2.5v for rest in center, and 0v for full revers.

They say it needs 5v for full left and 2.5v for rest in center, and 0v for full right.

The controller will mix the X-axis and Y-axis for tank drive. So I would assume I will need the Center Tap wire to read the joystick at center rest then right ?

What about the positive and negitive leads for the joystick ?

And actually this is for a heavy duty offroad power wheelchair, the stock 100 amp controller would just over heat in a matter of a few minutes and your stuck, I mounted a fan and that helped but only for a few more minutes, it finaly burned the boad and died, so I want a controller that will give me a little more power over a longer amount of time than the stock one did for only a few seconds. I really like the specs of the Roboteq AX2550HE. BUT for the same price I can just get the Ampflow.
 

ljcox

Well-Known Member
twinforced said:
The controller will mix the X-axis and Y-axis for tank drive. So I would assume I will need the Center Tap wire to read the joystick at center rest then right ?
No the centre tap is the reference point for the X and Y signals. It states in the data sheet you posted that the signals are wrt the centre tap.

Therefore, you need a differential amplifier with the centre tap connected to one input and the channel output to the other. It will need some gain and a voltage off set in order to create an output of 0 to 5V for the ampflow.
You need a diff amp for each channel.
twinforced said:
[
What about the positive and negitive leads for the joystick ?
The data sheet indicates that Vs (either +10 Volt or +12 Volt) goes to the red wire and the black goes to gnd.
 

twinforced

New Member
A differential amplifier ? Ok I need to look that up and understand what it is.
This is turning out to be more of a project learing how to wire it up than anything.... I'm sure I'll have many more dumb questions....
:rolleyes:
 

twinforced

New Member
Anyone here I can just send all this to and get it back ready to plug in ? LOL.


OK I was reading about them and all I can say is I'm screw'd. Looks like I need to find someone who can just do this for m as I'll just make a mess of it...
 
Last edited:

twinforced

New Member
What the Blue text ? If you dont like it please dont read my post. I came here looking for info and help not someone like you.

I dont care if you dont like it, if so many others do than BAN me. Or dont offer a color option !!!
 

ljcox

Well-Known Member
twinforced said:
Anyone here I can just send all this to and get it back ready to plug in ? LOL.

OK I was reading about them and all I can say is I'm screw'd. Looks like I need to find someone who can just do this for m as I'll just make a mess of it...
You did not answer my PM. Also, by starting 3 threads you have wasted my time as I did not initially realise that there was more than one.

The answers to the questions I asked (in response to the "What am I doing?" thread) were in this thread that I found by accident.

Nevertheless, I'm prepared to design it for you, but

1. I'm not prepared to build it for you, but I can advise you through it.

2. I need one more piece of info.

Does anyone know if the ampflow unit has over and under voltage protection on its inputs? The site posted by "twinforced" is light on for detail.

Is there another more advanced data sheet?
 
Last edited:

justDIY

Active Member
might I suggest

for true tank steering, consider two sticks, with only one axis each. this way you can have one motor in forward and one in reverse for 0 turning radius

alternately, perhaps the onboard microcontroller can be programmed as such

Y = Up X = Center, both motors forward
Y = Center X = Left, left motor reverse, right motor forward (turn left)
Y = Center X = Right, left motor forward, right motor reverse (turn right)
Y = Down X = Center, both motors reverse

edit:

or how about starting off with an easier joystick, like an electromechanical (potentiometers) one that the controller is designed to work with.
 

twinforced

New Member
justDIY said:
or how about starting off with an easier joystick, like an electromechanical (potentiometers) one that the controller is designed to work with.
I had this one on hand, I will see about one like you are talking about.

I did get this from Penny & Giles.

Michael,



The center tap is so you can supply the joystick with a +/- input. If you have a +/- 15VDC supply then you will have three wires +15. -15 and common. Common would go to the center tap. If you have a single ended supply then you ignore it.



Regards,



Mark Vandersluis

Penny & Giles Controls Inc.

A Curtiss Wright Company

Tel: 919-303-4552

Fax: 919-303-9191

Mobile: 919-413-8909

Email: [email protected]

Website: www.pennyandgiles.com
 

twinforced

New Member
ljcox said:
You did not answer my PM. Also, by starting 3 threads you have wasted my time as I did not initially realise that there was more than one.
I was just try'n to get more exposer, maybe someone doesn't check all the forums.

And yes they do have a better data sheet but you have to down load it from the site.
 
Status
Not open for further replies.

Latest threads

EE World Online Articles

Loading
Top