Posts made by Kruix

@dc42
The MotorStepsToCartisian is a forward kinematic, is that function necessary to implement for testing?

Hello, I would like to implement the firmware for a 3RRR Scara,
which uses 3 Arms/Motors to set the XY position.
is there an easy way to test the kinematic from a function that outputs the coresponding angles from the backward transformation? ie.
The function outputs the angles for the motors from (0,0) after Homing.

vector<double> CalculateAngles(double x, double y, double rot, double l1, double l2,
                   double R, double r)
{
    double pi=3.14159265358979;
    vector<double> phi= {7*pi/6, 11*pi/6, pi/2};
    vector<double> my= {pi/6, 5*pi/6, 3*pi/2};
    vector<double> E= {0, 0, 0};
    vector<double> F= {0, 0, 0};
    vector<double> G= {0, 0, 0};
    vector<double> K= {0, 0, 0};
    vector<double> theta= {0, 0, 0};
    for(int i=0; i<3;i++){
        E[i] = -2*l1*(y+r*sin(rot+phi[i])+R*sin(my[i]));
        F[i] = -2*l1*(x+r*cos(rot+phi[i])+R*cos(my[i])); 
        G[i] = pow(x+r*cos(rot+phi[i])+R*cos(my[i]),2.0)+ pow(y+r*sin(rot+phi[i])+R*sin(my[i]),2.0)+pow(l1,2.0)-pow(l2,2.0);
        K[i] = sqrt(pow(E[i],2.0)+pow(F[i],2.0)-pow(G[i],2.0));
        theta[i] = 2*atan2((-E[i]+K[i]),(G[i]-F[i]));
    }
    vector<double> theta_temp =cart2threeRRR(0,0,rot,l1,l2,R,r);
    theta[0]=theta[0]-theta_temp[0];
    theta[1]=theta[1]-theta_temp[1];
    if(theta[2]>3){theta[2]=theta[2]-2*Pi;}
    theta[2]=theta[2]-theta_temp[2];
    return theta;

@jay_s_uk You are totally right, I was questioning my sanity but I tried the same with a different driver and it worked now. I guess that my driver was broken. There were also some software issues.Thanks everyone for your help!

@jay_s_uk
The question was because of the article in https://docs.duet3d.com/User_manual/Overview/Getting_started_Duet_3_MB6XD
that states at the bottom that
"The Step, Dir and Enable outputs from the 6XD are either low (when "on") or floating/high impedence when "off". "
thats why I assumed the R command would only refer to the Polarity of the Enable Pin

@T3P3Tony
Is it possible to set the STEP/DIR Signal itself active High instead of pulling it to ground?

@T3P3Tony
Firstly thanks for the support!
changing the Polarity didn't work. But one more question, if there is no error signal of a motor, nothing needs to be connected there, right?
What Polarity does the jumper change? Is the standard active high or low?

@T3P3Tony

https://docs.duet3d.com/User_manual/Connecting_hardware/Motors_connecting_external

Yes it didn't make sense to me too at least

@dc42 It didnt work with 1k or 500ohms pullup resistors

@dc42
I will try that out, thank you.
Is the wiring correct with?
EN -EN
STEP - STEP
DIR -DIR
GROUND -GROUND
or should it be connected like the polulu in the image above?

@dc42
Thank you for the reply.
Datasheet:
https://henschel-robotics.ch/wp-content/uploads/2022/04/Manual_HDrive.pdf
Model: 17ETH-i
Configuration:

I have tried to use the Motor in the active high and active low configuration before.
I have found that the Signal voltage when the Motors where connected was pretty low (Amplitude of 0.8V)even when I have set the setting in the duet active high and also tried using 10k pullups to 5V
For me it looks as if it wasn't optically isolated as there are only 4 ESDG wires
I have also tried to crosswire like in the image:

as in https://docs.duet3d.com/User_manual/Connecting_hardware/Motors_connecting_external
The Firmware is Reprap the latest stable version for Duet and
The Board is run over a Raspberry Pi 3B connected with an external 5V power supply and connected over the Serial cables.
The USB is not connected.

Hello, I am having problems with connecting an external Stepper motor driver to the Duet
It seems that the motor driver can't find a signal

Mainboard: Duet3 6XD
Steppermotor driver: Step/Dir/Enable Interface, with maximum Connection rate up to 10kHz
Stepper motor: NEMA17

Connection
Stepper driver<->Duet3 6XD Driver_0
DIR<->DIR
STEP<->STEP
ENABLE<->ENABLE
GROUND<->GROUND

1. Are Pull-ups for the Signals needed?
2. Is it sufficient for the config file to specify
   for the external Driver to work?

---

M569 P0 S1; drive 0 goes forward
M584 X0 ; drive mapping
M350 X16 ;microstepping
M569 P0 R0 T167:167:167:0 //low enable, time set to approx 6 kHz
//
M92 X20.0
M566 X1000
M203 X6000
M906 X1000
M84 S200

---

Thanks in advance