Published October 30, 2018 © GPL3+

Project ZERBERUS - Robotic Dog

I'm trying to build a four legged walking Robot that is inspired by the Boston Dynamics Spot Mini and James Bruton's OpenDog.

AdvancedWork in progress3,477

Things used in this project

Hardware components

Relay (generic)

MOSFET (generic)

5V Voltage regulator (generic)

6V Voltage regulator (generic)

Arduino Mega 2560

Diode (generic)

Resistor 1k ohm

Perfboard

180 Servo (generic)

DC motor (generic)

Rotary potentiometer (generic)

Lead screws and Nuts T8

Ball Bearings (generic)

Stock material

Nuts and Bolts

Hand tools and fabrication machines

3D Printer (generic)

Lathe (generic)

Soldering iron (generic)

General workshop supplies

Story

What is Project ZERBERUS? I would define it as kind of a poor mans Spot Mini. I was always intrigued by walking Robots and wanted to try to make my own. Because of my budget limitations I maybe opted for somewhat hacky solutions sometimes. Also I almost only used raw stock and did a lot of machining again to reduce the cost.

Im currently at a stage where I have a decent homing sequence going. The electronics and structural components are basically done and Im hoping to get it actually walking in the next couple of months. To avoid confusion Ive built my own motor controller thats why you need these Relais. But you could of course just use regular Motor controllers. You shouldnt see this whole thing as a step by step guide but rather as an inspiration.

If anyone needs CAD files or help with the electronics side of things Im happy to answer any questions. Also If you want plans I unfortunately only can send you my drawings as there isnt a complete CAD model

Schematics

Code

Project_ZERBERUS

# include <PID_v1.h>
#include <Wire.h>

#define hipvl1 22
#define hipvl2 23
#define hipvr1 24
#define hipvr2 25
#define hiphl1 26
#define hiphl2 27
#define hiphr1 28
#define hiphr2 29

#define kneevl1 30
#define kneevl2 31
#define kneevr1 32
#define kneevr2 33
#define kneehl1 34
#define kneehl2 35
#define kneehr1 36
#define kneehr2 37 

#define potkvl A0
#define potkvr A1
#define potkhl A2  
#define potkhr A3
#define pothvl A4
#define pothvr A5
#define pothhl A6
#define pothhr A7

#define remote1 A8
#define remote2 A9

int neigung;
int hiplean = 8; //allgemeiner Neigungswert fr Hfen

int vl;
int vr;
int hl;
int hr;

double Kp=0.03, Ki=0.6, Kd=0.6; 

double kneevlset;
double kneevrset;
double kneehlset;
double kneehrset;
double hipvlset;
double hiphlset;
double hipvrset;
double hiphrset;

double kneevlinp;
double kneevrinp;
double kneehlinp;
double kneehrinp;
double hipvlinp;
double hiphlinp;
double hipvrinp;
double hiphrinp;


double kneevloutp;
double kneevroutp;
double kneehloutp;
double kneehroutp;
double hipvloutp;
double hiphloutp;
double hipvroutp;
double hiphroutp;

int kneevl_;
int kneevr_;
int kneehl_;
int kneehr_;
int hipvl_;
int hipvr_;
int hiphl_;
int hiphr_;

PID kneevlPID (&kneevlinp, &kneevloutp, &kneevlset, Kp, Ki, Kd, DIRECT);
PID kneevrPID (&kneevrinp, &kneevroutp, &kneevrset, Kp, Ki, Kd, DIRECT);
PID kneehlPID (&kneehlinp, &kneehloutp, &kneehlset, Kp, Ki, Kd, DIRECT);
PID kneehrPID (&kneehrinp, &kneehroutp, &kneehrset, Kp, Ki, Kd, DIRECT);
PID hipvlPID (&hipvlinp, &hipvloutp, &hipvlset, Kp, Ki, Kd, DIRECT);
PID hipvrPID (&hipvrinp, &hipvroutp, &hipvrset, Kp, Ki, Kd, DIRECT);
PID hiphlPID (&hiphlinp, &hiphloutp, &hiphlset, Kp, Ki, Kd, DIRECT);
PID hiphrPID (&hiphrinp, &hiphroutp, &hiphrset, Kp, Ki, Kd, DIRECT);

void setup() {
  pinMode(hipvl1,OUTPUT);
  pinMode(hipvl2,OUTPUT);
  pinMode(hipvr1,OUTPUT);
  pinMode(hipvr2,OUTPUT);
  pinMode(hiphl1,OUTPUT);
  pinMode(hiphl2,OUTPUT);
  pinMode(hiphr1,OUTPUT);
  pinMode(hiphr2,OUTPUT);

  pinMode(kneevl1,OUTPUT);
  pinMode(kneevl2,OUTPUT);
  pinMode(kneevr1,OUTPUT);
  pinMode(kneevr2,OUTPUT);
  pinMode(kneehl1,OUTPUT);
  pinMode(kneehl2,OUTPUT);
  pinMode(kneehr1,OUTPUT);
  pinMode(kneehr2,OUTPUT);

  pinMode(potkvl,INPUT);
  pinMode(potkvr,INPUT);
  pinMode(potkhl,INPUT);
  pinMode(potkhr,INPUT);
  pinMode(pothvl,INPUT);
  pinMode(pothvr,INPUT);
  pinMode(pothhl,INPUT);
  pinMode(pothhr,INPUT);

  pinMode(remote1,INPUT);
  pinMode(remote2,INPUT);

  kneevlPID.SetMode(AUTOMATIC);
  kneevlPID.SetOutputLimits(0,100);
  kneevlPID.SetTunings(Kp, Ki, Kd);
  kneevlPID.SetSampleTime(100);

  kneevrPID.SetMode(AUTOMATIC);
  kneevrPID.SetOutputLimits(0,100);
  kneevrPID.SetTunings(Kp, Ki, Kd);
  kneevrPID.SetSampleTime(100);

  kneehlPID.SetMode(AUTOMATIC);
  kneehlPID.SetOutputLimits(0,100);
  kneehlPID.SetTunings(Kp, Ki, Kd);
  kneehlPID.SetSampleTime(100);

  kneehrPID.SetMode(AUTOMATIC);
  kneehrPID.SetOutputLimits(0,100);
  kneehrPID.SetTunings(Kp, Ki, Kd);
  kneehrPID.SetSampleTime(100);

  hipvlPID.SetMode(AUTOMATIC);
  hipvlPID.SetOutputLimits(0,100);
  hipvlPID.SetTunings(Kp, Ki, Kd);
  hipvlPID.SetSampleTime(100);

  hipvrPID.SetMode(AUTOMATIC);
  hipvrPID.SetOutputLimits(0,100);
  hipvrPID.SetTunings(Kp, Ki, Kd);
  hipvrPID.SetSampleTime(100);

  hiphlPID.SetMode(AUTOMATIC);
  hiphlPID.SetOutputLimits(0,100);
  hiphlPID.SetTunings(Kp, Ki, Kd);
  hiphlPID.SetSampleTime(100);

  hiphrPID.SetMode(AUTOMATIC);
  hiphrPID.SetOutputLimits(0,100);
  hiphrPID.SetTunings(Kp, Ki, Kd);
  hiphrPID.SetSampleTime(100);
  
  Serial.begin(9600);
  Wire.begin();  
  HOME();
}

void loop() {

}

  void hipbend() {



    int hipvl_ = analogRead(pothvl);
    int hipvr_ = analogRead(pothvr);
    int hiphl_ = analogRead(pothhl);
    int hiphr_ = analogRead(pothhr);

    int hipleanvl = hipvl_; // aktueller Wert der Hftgelenke
    int hipleanvr = hipvr_;
    int hipleanhl = hiphl_;
    int hipleanhr = hiphr_;

    vl = 1;
    vr = 1;
    hl = 1;
    hr = 1;

if (neigung == 1)
  {
    hipvl_ = hipvl_ - hiplean; //Sollwert fr die Hftneigung
    hiphl_ = hiphl_ - hiplean;
    hipvr_ = hipvr_ + hiplean;
    hiphr_ = hiphr_ + hiplean;
  }

else if (neigung == 0)
  {
    hipvl_ = hipvl_ + hiplean; //Sollwert fr die Hftneigung
    hiphl_ = hiphl_ + hiplean;
    hipvr_ = hipvr_ - hiplean;
    hiphr_ = hiphr_ - hiplean;
  }

      if (hipvl_ > hipleanvl)
      {
        hipvlout();
        //hipvl nach innen 
      }

      else if (hipvl_ < hipleanvl)
      {
        hipvlin();
        //hipvl nach auen
      }

       else if (hipvl_ = hipleanvl)
      {

      }
 
      if (hipvr_ > hipleanvr)
        {
          hipvrin(); 
           //hipvr nach innen
        }

        else if (hipvr_ < hipleanvr)
        {
          hipvrout();
          //hipvr nach auen
        }

        else if (hipvr_ = hipleanvr)
        {

        }

          if (hiphl_ > hipleanhl)
          {
            hiphlout();
            //hiphl nach innen
          }

          else if (hiphl_ < hipleanhl)
          {
            hiphlin();
            //hiphl nach auen
          }

           else if (hiphl_ = hipleanhl)
          {

          }


            if (hiphr_ > hipleanhr)   
            {
              hiphrout();
              //hiphr nach innen
            }

            else if (hiphr_ < hipleanhr)   
            {
              hiphrin();
              //hiphr nach auen
            }

            
            else if (hiphr_ = hipleanhr)   
            {

            }

if (neigung == 1)
  {  
    while(vl==1 || vr==1 || hl==1 || hr==1)
    {
      if(analogRead(pothvl) <= hipvl_)
      {
        vl = 0;
        hipvllow();
        //hipvl low
      }

      if(analogRead(pothvr) >= hipvr_)
      {
        vr = 0;
        hipvrlow();
        //hipvr low
      }

      if(analogRead(pothhl) <= hiphl_)
      {
        hl = 0;
        hiphllow();
        //hiphl low 
      }

      if(analogRead(pothhr) >= hiphr_)
      {
        hr = 0;
        hiphrlow();
        //hiphr low
      }
       delay(500);   
    }

  }

              if (neigung == 0)
                {  
                  while(vl==1 || vr==1 || hl==1 || hr==1)
                  {
                    if(analogRead(pothvl) >= hipvl_)
                    {
                      vl = 0;
                      hipvllow();
                      //hipvl low
                    }
              
                    if(analogRead(pothvr) <= hipvr_)
                    {
                      vr = 0;
                      hipvrlow();
                      //hipvr low
                    }
              
                    if(analogRead(pothhl) >= hiphl_)
                    {
                      hl = 0;
                      hiphllow();
                      //hiphl low 
                    }
              
                    if(analogRead(pothhr) <= hiphr_)
                    {
                      hr = 0;
                      hiphrlow();
                      //hiphr low
                    }
                    delay(500);    
                  }
              
                }
    
  }

  
   void hipvlin ()
  {
    digitalWrite(hipvl2,HIGH);
    digitalWrite(hipvl1,LOW);
    Serial.println("hipvlin");
  }

   
   void hipvlout ()
  {
    digitalWrite(hipvl1,HIGH);
    digitalWrite(hipvl2,LOW);
    Serial.println("hipvlout");
  }
   
   void hipvrin ()
  {
    digitalWrite(hipvr2,HIGH);
    digitalWrite(hipvr1,LOW);
    Serial.println("hipvrin");
  }
   
   void hipvrout ()
  {
    digitalWrite(hipvr1,HIGH);
    digitalWrite(hipvr2,LOW);
    Serial.println("hipvrout");
  }
   
   void hiphlin ()
  {
    digitalWrite(hiphl2,HIGH);
    digitalWrite(hiphl1,LOW);
    Serial.println("hiphlin");
  }
   
   void hiphlout ()
  {
    digitalWrite(hiphl1,HIGH);
    digitalWrite(hiphl2,LOW);
    Serial.println("hiphlout");
  }
   
   void hiphrin ()
  {
    digitalWrite(hiphr2,HIGH);
    digitalWrite(hiphr1,LOW);
    Serial.println("hiphrin");
  }
   
   void hiphrout ()
  {
    digitalWrite(hiphr1,HIGH);
    digitalWrite(hiphr2,LOW);
    Serial.println("hiphrout");
  }
   
   void kneevlin ()
  {
    digitalWrite(kneevl2,HIGH);
    digitalWrite(kneevl1,LOW);
    Serial.println("kneevlin");
  }

   void kneevlout ()
  {
    digitalWrite(kneevl1,HIGH);
    digitalWrite(kneevl2,LOW);
    Serial.println("kneevlout");
  }

   
   void kneevrin ()
  {
    digitalWrite(kneevr2,HIGH);
    digitalWrite(kneevr1,LOW);
    Serial.println("kneevrin");
  }
   
   void kneevrout ()
  {
    digitalWrite(kneevr1,HIGH);
    digitalWrite(kneevr2,LOW);
    Serial.println("kneevrout");
  }
   
   void kneehlin ()
  {
    digitalWrite(kneehl2,HIGH);
    digitalWrite(kneehl1,LOW);
    Serial.println("kneehlin");
  }
   
   void kneehlout ()
  {
    digitalWrite(kneehl1,HIGH);
    digitalWrite(kneehl2,LOW);
    Serial.println("kneehlout");
  }
   
   void kneehrout ()
  {
    digitalWrite(kneehr2,HIGH);
    digitalWrite(kneehr1,LOW);
    Serial.println("kneehrin");
  }
   
   void kneehrin ()
  {
    digitalWrite(kneehr1,HIGH);
    digitalWrite(kneehr2,LOW);
    Serial.println("kneehrout");
  }
   
   void  hipvllow()
  {
    digitalWrite(hipvl1,LOW);
    digitalWrite(hipvl2,LOW);
    Serial.println("hipvllow");
  }

   
   void  hipvrlow()
  {
    digitalWrite(hipvr1,LOW);
    digitalWrite(hipvr2,LOW);
    Serial.println("hipvrlow");
  }
   
   void  hiphllow()
  {
    digitalWrite(hiphl1,LOW);
    digitalWrite(hiphl2,LOW);
    Serial.println("hiphllow");
  }
   
   void  hiphrlow()
  {
    digitalWrite(hiphr1,LOW);
    digitalWrite(hiphr2,LOW);
    Serial.println("hiphrlow");
  }
   
   void  kneevllow()
  {
    digitalWrite(kneevl1,LOW);
    digitalWrite(kneevl2,LOW);
    Serial.println("kneevllow");
  }
   
   void  kneevrlow()
  {
    digitalWrite(kneevr1,LOW);
    digitalWrite(kneevr2,LOW);
    Serial.println("kneevrlow");
  }
   
   void  kneehllow()
  {
    digitalWrite(kneehl1,LOW);
    digitalWrite(kneehl2,LOW);
    Serial.println("kneehllow");
  }
   
   void  kneehrlow()
  {
    digitalWrite(kneehr1,LOW);
    digitalWrite(kneehr2,LOW);
    Serial.println("kneehrlow");
  }

         
   void kneevl()
  {
kneevl_ = 0;    
while(kneevl_ == 0)
  {
    kneevlinp = map(analogRead(potkvl),235,453,0,10);

    kneevlPID.Compute();

      if(map(analogRead(potkvl),235,453,0,10) > kneevlset)
      {
        kneevlout();
        delay(kneevloutp);
      }
    
      if(map(analogRead(potkvl),235,453,0,10) < kneevlset)
      {
        kneevlin();
        delay(kneevloutp);
      }
    
      
      if(map(analogRead(potkvl),235,453,0,10) == kneevlset)
      {        
        kneevllow();
        kneevl_ = 1;
      }
  }
  }

//_______________________________________________________________________________________

   void kneevr()
  {
kneevr_ = 0;
while(kneevr_ == 0)
 {
    kneevrinp = map(analogRead(potkvr),400,680,0,10);

    kneevrPID.Compute();

      if(map(analogRead(potkvr),400,680,0,10) > kneevrset)
      {
        kneevrout();
        delay(kneevroutp);
      }
    
      if(map(analogRead(potkvr),400,680,0,10) < kneevrset)
      {
        kneevrin();
        delay(kneevroutp);
      }
    
      
      if(map(analogRead(potkvr),400,680,0,10) == kneevrset)
      {        
        kneevrlow();
        kneevr_ = 1;
      }
  }
  }

//_______________________________________________________________________________________


   void kneehl()
  {
kneehl_ = 0;
while(kneehl_ == 0)
 {
    kneehlinp = map(analogRead(potkhl),171,383,0,10);

    kneehlPID.Compute();

      if(map(analogRead(potkhl),171,383,0,10) > kneehlset)
      {
        kneehlout();
        delay(kneehloutp);
      }
    
      if(map(analogRead(potkhl),171,383,0,10) < kneehlset)
      {
        kneehlin();
        delay(kneehloutp);
      }
    
      
      if(map(analogRead(potkhl),171,383,0,10) == kneehlset)
      {        
        kneehllow();
        kneehl_ = 1;
      }
  }
  }
  
//_______________________________________________________________________________________


   void kneehr()
  {
kneehr_ = 0;    
while(kneehr_ == 0)
  {  
    kneehrinp = map(analogRead(potkhr),418,671,0,10);

    kneehrPID.Compute();

      if(map(analogRead(potkhr),418,671,0,10) > kneehrset)
      {
        kneehrout();
        delay(kneehroutp);
      }
    
      if(map(analogRead(potkhr),418,671,0,10) < kneehrset)
      {
        kneehrin();
        delay(kneehroutp);
      }
    
      
      if(map(analogRead(potkhr),418,671,0,10) == kneehrset)
      {        
        kneehrlow();
        kneehr_ = 1; 
      }
  }
  }

//_______________________________________________________________________________________


   void hipvl()
  {
hipvl_ = 0;    
while(hipvl_ == 0)
    {
    hipvlinp = map(analogRead(pothvl),95,247,0,10);

    hipvlPID.Compute();
Serial.print(hipvlinp);
      if(map(analogRead(pothvl),95,247,0,10) < hipvlset)
      {
        hipvlout();
        delay(hipvloutp);
      }
    
      else if(map(analogRead(pothvl),95,247,0,10) > hipvlset)
      {
        hipvlin();
        delay(hipvloutp);
      }
    
      
      else if(map(analogRead(pothvl),95,247,0,10) == hipvlset)
      {        
        hipvllow();
        hipvl_ = 1;
      }
  }
  }

//_______________________________________________________________________________________


   void hipvr()
  {
hipvr_ = 0;    
while(hipvr_ == 0)
{
    hipvrinp = map(analogRead(pothvr),825,967,0,10);

    hipvrPID.Compute();

      if(map(analogRead(pothvr),825,967,0,10) < hipvrset)
      {
        hipvrout();
        delay(hipvroutp);
      }
    
      if(map(analogRead(pothvr),825,967,0,10) > hipvrset)
      {
        hipvrin();
        delay(hipvroutp);
      }
    
      
      if(map(analogRead(pothvr),825,967,0,10) == hipvrset)
      {        
        hipvrlow();
        hipvr_ = 1; 
      }
  }
  }

//_______________________________________________________________________________________


   void hiphl()
  {
hiphl_ = 0;    
while(hiphl_ == 0)
    {
    hiphlinp = map(analogRead(pothhl),800,932,0,10);

    hiphlPID.Compute();

      if(map(analogRead(pothhl),800,932,0,10) < hiphlset)
      {
        hiphlout();
        delay(hiphloutp);
      }
    
      if(map(analogRead(pothhl),800,932,0,10) > hiphlset)
      {
        hiphlin();
        delay(hiphloutp);
      }
    
      
      if(map(analogRead(pothhl),800,932,0,10) == hiphlset)
      {        
        hiphllow();
        hiphl_ = 1;
      }
  }
  }

//_______________________________________________________________________________________


   void hiphr()
  {
hiphr_ = 0;    
while(hiphr_ == 0)
   { 
    hiphrinp = map(analogRead(pothhr),94,204,0,10);

   hiphrPID.Compute();

      if(map(analogRead(pothhr),94,204,0,10) < hiphrset)
      {
        hiphrout();
        delay(hiphroutp);
      }
    
      if(map(analogRead(pothhr),94,204,0,10) > hiphrset)
      {
        hiphrin();
        delay(hiphroutp);
      }
    
      
      if(map(analogRead(pothhr),94,204,0,10) == hiphrset)
      {        
        hiphrlow();
        hiphr_ = 1;
      }
  }
  }

//_______________________________________________________________________________________

void HOME()
{
kneevlset = 6;
kneevrset = 7;
kneehlset = 6;
kneehrset = 6;
hipvlset = 9;
hiphlset = 9;
hipvrset = 9;
hiphrset = 9;

     
     hipvl();
     delay(500);
     
     hiphl();
     delay(500);
     
     hiphr();
     delay(500);
     
     hipvr();
     delay(500);

     kneevl();
     delay(500);
     
     //kneehl();
     //delay(500);
     
     kneehr();
     delay(500);
     
     kneevr();
     delay(500);
     
     

  int servovl = 80;
  int servovr = 80;
  int servohl = 110;
  int servohr = 30;

  Wire.beginTransmission(8);
  Wire.write(servovl);
  Wire.write(servovr);
  Wire.write(servohl);
  Wire.write(servohr);
  Wire.endTransmission();
}

Project ZERBERUS - Robotic Dog

Things used in this project

Hardware components

Hand tools and fabrication machines

Story

Custom parts and enclosures

Hip Joint

Hip Joint Stabilizer

Schematics

Concept of my motor controller

Code