[jeffserv]

Greetings all,

Press Brake with Linear Encoders with a Reference Mark: How to wire to Kanalog Board. I have wire in incremental Encoders before.
Is there documentation as to how to wire a Quadrature Incremental Encoder with a Ref+ and Ref- also?

Thanks so much!

- Jeff

[TomKerekes]

Hi Jeff,

Encoder Ref Marks are handled in KFLOP/Kogna Software so can be connected to any available input. Differential signals can be connected to any unused A or B differential encoder input. Normally Kanalog JP2 is available. See Kanalog JP1/JP2 Differential Inputs.

For examples of how to home with index pulses see Axis Homing and Indexing.

[jeffserv]

Thanks Tom... looks good to me! Will give it a go!!

- Jeff

[jeffserv]

Next thing I am wondering?

How can I scale an analog input. The input is 7 to 1907. As wired with a potentiometer. I want that input to be scaled to 0 - 100. How can I do that?
Thanks!

[TomKerekes]

Hi Jeff,

What is the input used for? That would be (input - 7.0) * 100.0 / (1907.0 - 7.0)

[jeffserv]

I am using 3 different Potentiometers as inputs. I will use 1 analog output to supply the 10vdc to the three pot's.
Then the first pot. and analog input will be used to scale the dwell time after the bend on the press brake... 1 - 5 seconds.
Then the second pot will scale an offset to be put into the gain of the axis two. This will be anywhere from 0 - 250 thousands of an inch.
The third will be used to control the pressure setting of the press at 1 - 100 percent.

I will have a program running on the Kflop. No computer hooked up for running the machine, once dial in.

Thus I need to scale what ever the pot's are reading. I am using 10 turn pot's for accuracy.

[jeffserv]

Greetings,

Making progress. Have built an all new control. Wired up the valve system. Attached is the file I am running the machine with. As well as the init____.c file I am using. Not complete yet.

I am so far using jog... to limit switches. Down Button, Up Button, Down Foot Peddle. I have encoder feedback for both axis. Two hydraulic cylinders. Valve control for fast down, slow down, and fast return.
I have done step response tuning.... and able to get a profile move 2000 counts. And it moves pretty good on a single axis.

So I can jog, like Jog(0, 2000); Jog(1, 2000); and this moves down Pressing reasonably good. When it hits the switch it returns to the top. I have even tested some jogging to a ch0->Position and then reacting to this, which can be useful.
What I don't have... is closed loop motion... I am probably missing something... I have encoders that are 5080 cnts/inch. I can get action via the tuning... but not with a move command like this??? MoveRelAtVel(0, -5080, 2000); //MOVE UP ONE INCH

The code is debugged, but don't have that newest copy here. Another problem... with Jog... is that I have to Zero(0); Zero(1); both axis so that I can get them to move right away when commanded to jog.
As well the DEST does not match the Position.... the Dest is just running on and on... and the position of course is matching the linear encoders... for axis 0, 1. Most likely related to no closed loop???

Thanks for your help!

#include "KMotionDef.h"

// Press Brake Run Version 4.0.3
// ADDED RAPID
//120mm/s Approach
//10mm/s Pressing
//100mm/s Return

enum { HOME, RETURN1, RETURN2, IDLE, DOWN, DOWNFAST, UP, DELAY, BOTTOM, TOP, RETURN}; // states
#define CLOSE 136
#define OPEN 137
#define RAPID 140
#define TOP 139
#define BOTTOM 138
#define SLAVE 1

int state = IDLE;
int slow = 2000; //2000 for pressing 40000 High Speed
int medium = 20000;
int fast = 20000;
double DelayTime;
int offset; //OFFSET
int Y3 = 144;
int Y5 = 145;
int A0; //PRESSURE
float a10; //Dwell calculation
int a12; //Dwell calculation
int dwell; // Bend Delay
int cnt1 = 0; //Pressure OFF after count
int automode = 0; //Auto Mode
int position = 0; //Destination Position for leveling

main()
{
for (; //forever loop
{
switch (state)
{
//WAIT FOR COMMAND TO MOVE
case IDLE:
if (!ReadBit(BOTTOM) && ReadBit(CLOSE)){ SET_OFFSET(); state = DOWNFAST; } //SET_OFFSET();
if (!ReadBit(TOP) && ReadBit(OPEN)){ ZERODEST(); state = UP; }
cnt1++;
Delay_sec(0.01);
if (cnt1 >= 2){ V_IDLE(); } //PUT PRESS VALVES INTO IDLE MODE AFTER 2 10THS OF A SECOND.
break;

//GOING DOWN FAST
case DOWNFAST:
if (ReadBit(RAPID)){ V_APPROACH(); Jog(0, fast); Jog(1, fast); state = BOTTOM; } //FAST CLOSE //RAPID REVERSED FOR EXTERNAL SWITCH ACTIVATION.
if (ReadBit(BOTTOM)){ Jog(0, 0); Jog(1, 0); SET_DWELL(); state = DELAY; }
break;


//GOING DOWN
case DOWN:
if (!ReadBit(BOTTOM) && !ReadBit(RAPID)){ V_PRESSING(); Jog(0, slow); Jog(1, slow); state = BOTTOM; } //CHANGE TO SLOW CLOSE
if (ReadBit(BOTTOM)){ Jog(0, 0); Jog(1, 0); SET_DWELL(); state = DELAY; }
break;

//WAIT FOR LIMIT OR RELEASE OF (FOOT PEDDLE OR DOWN BUTTON).
case BOTTOM:
if (!ReadBit(CLOSE)){ Jog(0, 0); Jog(1, 0); cnt1 = 0; state = IDLE; }
if (ReadBit(BOTTOM)){ automode = 1; Jog(0, 0); Jog(1, 0); SET_DWELL(); state = DELAY; } //Put into auto mode.
break;

//DWELL AT BOTTOM
case DELAY:
if (Time_sec() > DelayTime){ state = UP; }
break;

//GOING UP
case UP:
if (!ReadBit(TOP)){ V_DECOMPRESSION(); Jog(0, -slow); Jog(1, -slow); state = RETURN; } //SLOW OPEN
if (ReadBit(TOP)){ Jog(0, 0); Jog(1, 0); ZERODEST(); cnt1 = 0; state = IDLE; }
break;

//RETURN AT MEDIUM SPEED
case RETURN:
if (!automode && !ReadBit(TOP)){ V_RETURN(); ZERODEST(); Jog(0, -medium); Jog(1, -medium); state = TOP; } //MEDIUM OPEN
if (automode && !ReadBit(TOP)){ V_RETURN(); ZERODEST(); Jog(0, -medium); Jog(1, -medium); state = HOME; } //AUTO GO TO TOP LIMIT THEN LEVEL
break;

//WAIT FOR LIMIT OR (RELEASE OF UP BOTTON IF NOT IN AUTO MODE).
case TOP:
if (!ReadBit(OPEN)){ Jog(0, 0); Jog(1, 0); ZERODEST(); cnt1 = 0; state = IDLE; } //STOP AND PUT BAKE INTO IDLE
if (ReadBit(TOP)){ Jog(0, 0); Jog(1, 0); ZERODEST(); cnt1 = 0; state = IDLE; }
break;

//AUTO GO TO TOP LIMIT THEN LEVEL
case HOME:
if (automode && ReadBit(TOP)){ V_IDLE(); Jog(0, 0); Jog(1, 0); ZERODEST(); automode = 0; }
//MOVE DOWN AND EVEN
if (!automode && ReadBit(TOP)){
int pos1 = ch0->Position;
int pos2 = ch1->Position;
position = pos2;
Delay_sec(0.1);
if (pos1 < pos2){ V_PRESSING(); Jog(0, slow); state = RETURN1; }
if (pos1 > pos2){ V_RETURN(); Jog(0, -slow); state = RETURN2; }
}
break;

case RETURN1:
if (ch0->Position >= position){V_IDLE(); Jog(0, 0); Jog(1, 0); ZERODEST(); cnt1 = 0; state = IDLE;}
break;

case RETURN2:
if (ch0->Position >= position){V_IDLE(); Jog(0, 0); Jog(1, 0); ZERODEST(); cnt1 = 0; state = IDLE;}
break;

}

}
}

//----------------------------------- VALVE CONTROL ------------------------------------------------------

V_IDLE()
{
//SET SPEED TO ZERO
int max = 0; ch0->MaxOutput = max; ch1->MaxOutput = max;
ClearBit(Y3);
ClearBit(Y5);
DAC(2,0); //Pressure Setting Zero
}

V_APPROACH()
{
//SET SPEED TO NORM
int max = 600; ch0->MaxOutput = max; ch1->MaxOutput = max;
SetBit(Y3);
SetBit(Y5);
A0 = ADC(0) * 2.12; //0 - 945 Reading Pressure Setting
DAC(2, -A0); //SET PRESSURE
}

V_PRESSING()
{
//SET SPEED TO MAX
int max = 2000; ch0->MaxOutput = max; ch1->MaxOutput = max;
ClearBit(Y3); //Experiment
SetBit(Y5);
A0 = ADC(0) * 2.12; //0 - 945 Reading Pressure Setting
DAC(2, -A0); //SET PRESSURE
}

V_DECOMPRESSION()
{

//SET SPEED TO ZERO THEN TO MINIMAL
int max = 0; ch0->MaxOutput = max; ch1->MaxOutput = max; //Instant Stop
ClearBit(Y3);
ClearBit(Y5);
Delay_sec(1.0);
int max = 100; ch0->MaxOutput = max; ch1->MaxOutput = max;
A0 = ADC(0) * 2.12; //0 - 945 Reading Pressure Setting
DAC(2, -A0); //SET PRESSURE

}

V_RETURN()
{
//REGULATE UP SPEED
int max = 300; ch0->MaxOutput = max; ch1->MaxOutput = max;
ClearBit(Y3);
ClearBit(Y5);
A0 = ADC(0) * 2.12; //0 - 945 Reading Pressure Setting
DAC(2, -A0); //SET PRESSURE
}

//------------------------------ SET DWELL -----------------------------------------------------------------

SET_DWELL()
{
a10 = ADC(1) / 189;
if (a10 > 189)
{
if (a10 > 0 && a10 <= 1){dwell = 1;}
if (a10 > 1 && a10 <= 2){dwell = 2;}
if (a10 > 2 && a10 <= 3){dwell = 3;}
if (a10 > 3 && a10 <= 4){dwell = 4;}
if (a10 > 4 && a10 <= 5){dwell = 5;}
}
if (a10 < 189){ dwell = 1; }
if (a10 < 0){ dwell = 1; }
DelayTime = Time_sec() + dwell; state = DELAY;
}

//------------------------------ SET OFFSET -----------------------------------------------------------------

SET_OFFSET()
{

int a3 = ADC(2);
int a5 = convert_value(a3);
ch0->MaxOutput = 600;
ch1->MaxOutput = a5;
//printf("Y1 MaxOutput = %d\n",a5);
state = DOWN;
}

convert_value(int a3){
// Calculate the scaling factor (avoid floating-point math).
int scale_factor = (620 - 610) * 1000 / (945 - 4);

// Apply the scaling factor to a3 and offset by 610 to get the new value.
int new_value = a3 * scale_factor / 1000 + 610;

return new_value; }

//---------------------------------------- ZERO DEST AND ALL -------------------------------------------------------------

ZERODEST()
{
ch0->Dest = 0; ch1->Dest = 0; Delay_sec(0.1);
}

ZERONOW()
{
Zero(0); Zero(1); Delay_sec(0.1);
}

#include "KMotionDef.h"

main()
{
ch0->InputMode=ENCODER_MODE;
ch0->OutputMode=DAC_SERVO_MODE;
ch0->Vel=1000;
ch0->Accel=400000;
ch0->Jerk=4e+06;
ch0->P=30;
ch0->I=0;
ch0->D=60;
ch0->FFAccel=0.025;
ch0->FFVel=1.2;
ch0->MaxI=1000;
ch0->MaxErr=2e+06;
ch0->MaxOutput=600;
ch0->DeadBandGain=1;
ch0->DeadBandRange=0;
ch0->InputChan0=0;
ch0->InputChan1=0;
ch0->OutputChan0=0;
ch0->OutputChan1=0;
ch0->MasterAxis=-1;
ch0->LimitSwitchOptions=0x100;
ch0->LimitSwitchNegBit=0;
ch0->LimitSwitchPosBit=0;
ch0->SoftLimitPos=1e+09;
ch0->SoftLimitNeg=-1e+09;
ch0->InputGain0=1;
ch0->InputGain1=1;
ch0->InputOffset0=0;
ch0->InputOffset1=0;
ch0->OutputGain=-1;
ch0->OutputOffset=0;
ch0->SlaveGain=1;
ch0->BacklashMode=BACKLASH_OFF;
ch0->BacklashAmount=0;
ch0->BacklashRate=0;
ch0->invDistPerCycle=1;
ch0->Lead=0;
ch0->MaxFollowingError=1000000000;
ch0->StepperAmplitude=20;

ch0->iir[0].B0=1;
ch0->iir[0].B1=0;
ch0->iir[0].B2=0;
ch0->iir[0].A1=0;
ch0->iir[0].A2=0;

ch0->iir[1].B0=1;
ch0->iir[1].B1=0;
ch0->iir[1].B2=0;
ch0->iir[1].A1=0;
ch0->iir[1].A2=0;

ch0->iir[2].B0=1;
ch0->iir[2].B1=0;
ch0->iir[2].B2=0;
ch0->iir[2].A1=0;
ch0->iir[2].A2=0;

ch1->InputMode=ENCODER_MODE;
ch1->OutputMode=DAC_SERVO_MODE;
ch1->Vel=1000;
ch1->Accel=400000;
ch1->Jerk=4e+06;
ch1->P=30;
ch1->I=0;
ch1->D=60;
ch1->FFAccel=0.025;
ch1->FFVel=1.2;
ch1->MaxI=1000;
ch1->MaxErr=2e+06;
ch1->MaxOutput=620;
ch1->DeadBandGain=1;
ch1->DeadBandRange=0;
ch1->InputChan0=1;
ch1->InputChan1=0;
ch1->OutputChan0=1;
ch1->OutputChan1=0;
ch1->MasterAxis=-1;
ch1->LimitSwitchOptions=0x100;
ch1->LimitSwitchNegBit=0;
ch1->LimitSwitchPosBit=0;
ch1->SoftLimitPos=1e+09;
ch1->SoftLimitNeg=-1e+09;
ch1->InputGain0=1;
ch1->InputGain1=1;
ch1->InputOffset0=0;
ch1->InputOffset1=0;
ch1->OutputGain=-1;
ch1->OutputOffset=0;
ch1->SlaveGain=1;
ch1->BacklashMode=BACKLASH_OFF;
ch1->BacklashAmount=0;
ch1->BacklashRate=0;
ch1->invDistPerCycle=1;
ch1->Lead=0;
ch1->MaxFollowingError=1000000000;
ch1->StepperAmplitude=20;

ch1->iir[0].B0=1;
ch1->iir[0].B1=0;
ch1->iir[0].B2=0;
ch1->iir[0].A1=0;
ch1->iir[0].A2=0;

ch1->iir[1].B0=1;
ch1->iir[1].B1=0;
ch1->iir[1].B2=0;
ch1->iir[1].A1=0;
ch1->iir[1].A2=0;

ch1->iir[2].B0=1;
ch1->iir[2].B1=0;
ch1->iir[2].B2=0;
ch1->iir[2].A1=0;
ch1->iir[2].A2=0;


EnableAxis(0);
EnableAxis(1);

DefineCoordSystem(0,1,-1,-1);
}

[TomKerekes]

Hi Jeff,

What I don't have... is closed loop motion...

I'm guessing you haven't properly tuned the axes. The Feed Forward is probably outputting something to the DAC to give some motion. The Max Following Error is set to a huge value so there isn't any fault when the axis doesn't follow properly. I would remove the FF and use the Step Response Screen to set the feedback parameters such that the position follows the command with low error.

With a slaved pair of axes like this it is somewhat tricky to tune. I'd try very small moves (with the other axis disabled) first to obtain some reasonable tuning. Then set the same parameters for both axes and Slave them and Tune the Master Axis with the Slave following. Then reverse the Master/Slave roles to tune the other axis.

[jeffserv]

Thanks Tom,

Got back into the tuning and figured out what was happening.

Back Story: When I first installed the board into the new control panel, it all work well at my shop. At the customers, when first hooked up, one of the switch outputs to a relay... was hooked to some bad existing wiring and shorted out that transistor chip on the Kanalog board. Had to switch to some other outputs to get it going. I replaced all the wiring going to the valve bank, and eliminated the problem. All new control with all new wiring. See Picture below.

Seems that this mishap, did something also to the analog out on channel 1. That was simply not working. I switched to channel 3 which was the next one available.

The whole system was a problem, as I was making channel 1 the master and channel 0 the slave. With channel 1 being bad... and not functioning properly... all sorts of problems.

By following your idea to go back to the tuning, I discovered this problem. Got full closed loop control now and the machine is accurate to the resolution of the linear encoders... 10 microns... or 0.000393701 of an Inch!

Of course bending metal will never achieve that type of accuracy... but the machine can.

Now converting programming to take advantage of the closed loop programming.

[TomKerekes]

Wow very neat wiring.

[jeffserv]

Wow very neat wiring.

Thanks... we pulled the control backplate completely out of the machine and brought to the shop... and built the control there. Then back to the customers and installed.

Not completely running yet. Adding features in the programming... at the customers request.

More later.

[jeffserv]

Greetings,

Now I am very close. I need in C programming to be able to do precise Coordinated motion? So that both axis move together and stay exactly in Sync.
I am going to put the init and c program on Thread 1 and 2. The press brake program will run the thread 1 and wait a few seconds, then load and run its forever loop.

I have four types of moves: DownFast, DownSlow, UpSlow, and UpMedium. slow = 2000; medium = 20000; fast = 24000; (cnts/sec).

Thanks in advance for your help!

[Fede_mmdtech]

Hi, i do have some experience in operating and repairing press brakes, the down or up movement does not require exact syncro. Usually they have a maximum umbalance set between Y1 and Y2(usually far from mechanical maximum desalingnment),that should trigger a stop, and a way to recover from unbalance (usually is moving up slow both cylinders to mechanical stop). During bending, you need to check if the final programmed point was reached, because you can have a lack of pressure (force), or a bad tool combination that can make imposible to the machine arrive to the desired position. I've already have done a vertical machining center retrofit with dynomotion and i'm thinking about doing a press brake with these boards too.

[jeffserv]

This machine was built to allow tilt via the control. When I first started programming it, could get it way out of "wack", even up to 6 inches. Tricky to get it back aligned.

Max Output and Amplitude settings were to low. Once I set the stepper amplitude to 100 and the Max Output to 2000, almost all my misalignment went away. I could get some accumulated error, so wrote the program to handle that at Top, before bend, and at the bottom.

I have used Dynomotion on many CNC machines and its response and accuracy are wonderful. I have used controls that cost way more and cannot even come close to the speed and response of Dynomotions boards.

I use one of my three potentiometer for adjustment of tilt, can tilt up to 1/4 of an inch. Used for straightening a tilted die, or for creating a fan effect on a part. Set at 50% no bend, set less than 50% less bend on the right. Set at more than 50%, more bend on the right. Will take effect on the next bend.

Machine has been in operation for over 2 months now. No complaints from the customer... The machine runs on a single file, no screen. The machine powers up and it homes. Three potentiometers to control Tilt, Delay at Bottom, and Pressure Max. Adjustable top stop, Micrometer adjustable bottom stop. And a wedge the takes it from fast to slow, on another micro-switch.

So it is a CNC Press Brake that is very much simple manual control. Anyone can walk up to and operate this machine, and get very accurate parts. The micrometer stops are mounted on a turret that allows up to 6 settings. Thus you could do six sequential bends.

Did I say no screen, or computer? Turn power on, push green home button, start bending parts. All manually set. Fast and simple!

Good day!