Jizzy the quadruped robot

Hey all :slight_smile:

After a lot of this forum help so finally I made my quadruped robot (for now still has two legs) walking!
(each legs ----> 3 servo motors for lateral and longitudinal leg movement + forearm vertical movement. In these videos lateral leg movement is disabled)

Here the medium speed walking:

Here the full speed walking (it’s almost running!)

In the future it will have a lot of sensors in the feet to determine where the ground is and it will have a lot of distance sensors to track objects to avoid collisions and to follow a specific path.

Here the last version of Jizzy before his first walk:

All four feet + tactile sensors mounted and working!

https://www.youtube.com/watch?v=FOkL9-2dtRY&feature=youtu.be

Hi all, Finally a first serious walk test of Jizzy!

I call this walk tipology as "furtive walk". I am working on trot walking tipology too.

Stay tuned!

https://www.youtube.com/watch?v=DBShB75TDak&feature=youtu.be

New video: http://www.youtube.com/watch?v=Zo5Anz8Kcjw&list=UU0K6KF9MrmigNbWyWlqrv7g

https://www.youtube.com/watch?v=ifpj2NZl7h4&feature=em-upload_owner

Here Jizzy trying his first real walk! I need to lift him a bit to let the actual weak servos can work propely. I lift Jizzy to get half of actual weight.

New servos arriving: From the actual Futaba S3003 servos to new and more powerful BlueBird BMS-620MG servos.

currently Jizzy does not use any method of automatic stabilization, and the four legs, at present, are not connected to the armpits and groin.

https://www.youtube.com/watch?v=JRKNEhy3EQU

Here jizzy walking with 4 shoes mounted! A bit better :)

Interesting project.

Are you using any sensors to determine the attitude of the main body e.g MPU 9510 (9 axis sensor), Are you getting any feedback from the feet to determine when they come in contact with the ground ? (I can't see from the video if you have a micro switch etc on the feet which you are using to do this)

Are you just looping the servo's though the same sequence ? or is there some feedback system that adjust the walk ?

Do the legs rotate at the hip? so that it can turn, i.e not just walk in straight lines ?

Are you going to post your code ?

rogerClark: Interesting project.

Are you using any sensors to determine the attitude of the main body e.g MPU 9510 (9 axis sensor), Are you getting any feedback from the feet to determine when they come in contact with the ground ? (I can't see from the video if you have a micro switch etc on the feet which you are using to do this)

Are you just looping the servo's though the same sequence ? or is there some feedback system that adjust the walk ?

Do the legs rotate at the hip? so that it can turn, i.e not just walk in straight lines ?

Are you going to post your code ?

Hi rogerClark! Until now no sensors is used to let Jizzy to balance himself. Sure this is one of next steps :) For this matter I am developing the new armpits and hips (the old versions of these components was weak and not precise cause I was using too long ties) to let Jizzy to mantain the correct balance;

the right example to let you understand what I mean (grr my poor english :( ) is the BostonDynamics Bigdog, when a man pushing him sideways getting bigdog spreading her legs to avoid losing his balance. Same thing will happen in Jizzy project. I was looking for MPU-6050 Accelerometer + Gyro but the MPU 9510 seems a lot better!

Over all that, yesterday I finished the code to let Jizzy to know when his feet touching the ground! All that using a 60cm long Force Sensitive Resistor from which I obtained 4 sensitive resistors (one for leg)!

It's a damn HOT AND GREAT thing because now Jizzy push the legs to let body advance ONLY when he know the single foot is in contact with the ground! This make Jizzy really more balanced, more precise when he is walking, and especially is the first project step to let the robot walking good on a not flat surface.

Until the foot is not touching the ground, Jizzy will advance his forearm in an attempt to reach the ground! It's hard with my english to make you understand good my words :( I hope today or tomorrow I will put a new youtube video :) So the the walking is not a simple predetermined script. It using a timer to rule the legs orders but that timer is modified by the 4 tactile feet sensors! (push to advance just when you are sure your foot is on the ground! If not you will fall down like a drugged cow!)

About the possibility of turning left or right, sure! is on the way :) And I am think about to use just the frontal legs or all 4 legs to let Jizzy turning good! Now there is 3 motors for 1 leg: A) Arm motor. Let the entire leg going forward and back (longitudinal) B) Forearm motor. Let the forearm going forward and back (longitudinal) C) Hip (or armpits) motor. Let the entire leg rotate in hip (or armpit) pivot. (like BostonDynamics Bigdog when trying to stay balanced after the man pushed him sideways)

I hope you understand something :( Really sorry for my funny english

You might want to re-think his name…

Hi @aldoz

Thanks for the information.

I hope you understand something smiley-sad Really sorry for my funny english

Yes. I totally understand. Thankyou.

I was looking for MPU-6050 Accelerometer + Gyro but the MPU 9510 seems a lot better!

I ordered some MPU 9510 from eBay 2 weeks ago.

http://www.ebay.com/itm/9DOF-MPU-9150-9-Axis-Accelerometer-Gyroscope-Magnetic-Field-Sensor-Moudle-/200949159205?pt=AU_B_I_Electrical_Test_Equipment&hash=item2ec980d525

But they have not arrived yet.

All that using a 60cm long Force Sensitive Resistor from which I obtained 4 sensitive resistors (one for leg)!

OK. So you measure the pressure on each foot? This seems like a good idea. I don't think I could walk if I could not feel the pressure on ,my feet ;-)

Perhaps the feet need more friction with the ground. They look like they are slipping.

Anyway. Good luck with the project, it looks like you are making great progress.

Edit. Just looked a the price of Force Resistors.. $$$$

I wonder if it would be cheaper to buy some small digital scales and take out the sensor

http://www.ebay.com.au/itm/Jewelry-Scale-1000g-500g-300g-200g-0-1g-0-01g-Balance-Pocket-Digital-Weighing-/261540079324?pt=LH_DefaultDomain_15&var=&hash=item3ce500e6dc

But as you already have the Force Resistor, I suppose there is no reason.

But for anyone else building one, this may be a cheaper option, (albeit it needs other electronics to read the sensor)

OK. So you measure the pressure on each foot? This seems like a good idea. I don't think I could walk if I could not feel the pressure on ,my feet ;-)

Perhaps the feet need more friction with the ground. They look like they are slipping.

Yeah all single foot sensitive sensors giving to Jizzy brain the value of the weight the leg must face! So Jizzy from these informations can already understand his balance and especially understand how much the leg (then the servos)is striving!

Perhaps the feet need more friction with the ground. They look like they are slipping.

Yes, I mounted 4 shoes to Jizzy feet to try to get more grip but I need to optimize the walking behaviour too to let Jizzy legs correctly grip the ground.

Anyway. Good luck with the project, it looks like you are making great progress.

Thank you so mutch! :open_mouth:

@JimboZA: LOL :grin:

--------------------------- EDIT -----------------------

Edit. Just looked a the price of Force Resistors.. $$$$

I wonder if it would be cheaper to buy some small digital scales and take out the sensor

http://www.ebay.com.au/itm/Jewelry-Scale-1000g-500g-300g-200g-0-1g-0-01g-Balance-Pocket-Digital-Weighing-/261540079324?pt=LH_DefaultDomain_15&var=&hash=item3ce500e6dc

But as you already have the Force Resistor, I suppose there is no reason.

But for anyone else building one, this may be a cheaper option, (albeit it needs other electronics to read the sensor)

If you want I can give you a video showing how to obtain many FSR from a single 60cm long resistor!

If you want I can give you a video showing how to obtain many FSR from a single 60cm long resistor!

Good point ;-)

rogerClark:

If you want I can give you a video showing how to obtain many FSR from a single 60cm long resistor!

Good point :wink:

:slight_smile:

My method is a bit different (in the final shape of the cutted sensor; I made some other cuts that determine the final shape) but this one it’s working good too

Very cool. and cost effective

Here the new JQR (Jizzy quadruped robot) video:

JQR v12.0 Added 8 new more powerful servo (4x Bluebird BMS-620 and 4x Bluebird BMS-620MG) - 140 degree rotation ( :roll_eyes: ).

In this video: Setting legs position using a fictitious measure ground. This method is really nice 'cause now I can set precisely the legs position (finally!)

This is dramatic important because a little imprecision will cause a not coordinated and disordered walk then will produce a unbalanced robot.

Over, I really can't wait to test new Bluebird servos! Jizzy is near to do his first not helped walk!

https://www.youtube.com/watch?v=VK_OCRUm4o4&feature=youtu.be

Hi all guys, For the first time JQR is walking alone and without help!

I am really satisfied because I needed over 5 months of hard work and many tests to achieve this result!

The JQR is not yet really precise but now it's walking without human help :)

Nexts project steps: 1) optimize the walk to obtain a straight walk line (now JQR slightly turning right while walking)

2) code the turn right/left procedure

3) modify the code to use the 4 tactile sensors on the JQR feet (for now disabled)

Here the video: https://www.youtube.com/watch?v=rqQEU_2DJrk

Hi again guys! This is the latest version of JQR walking.

In this video you can see the JQR using new front legs balancing code to help rear legs to advance without losing balance.

But already old! I am developing the new feet, more stable, more precise, more solid. Stay tuned ;)

http://www.youtube.com/watch?v=qv204Chl6ig

Hi guys, here the JQR (v19.0) trying for the first time his new MMA7361 accellerometer!

It's a bit complex to describe but this fantastic, little, cheap sensor can calc both the accelleration and the actual position too for the 3 axis! (I think the standard 1g gravity force affect the rotated body even when no external forces are not present)

In this video you can see how the MMA7361 X-pos value changing when I rotate the robot (pitch) Thanks to this sensor I can teach Jizzy to find always the correct balance!

http://youtu.be/JU-nkfrcbuM