1/26/2026 8:47 PM - watched a lot of videos on how to do this and design ideas

i found some videos that explained how to make a robotic dog and how they were going to make the leg mechanisms there were a lot of different people who have done this in many different ways I'm thinking about two of the main ways but I'm thinking I'm going to want 12 servos 3 for each leg one to point it outward and then two to control full leg rotation and then the knee part.

some videos i watched

1/26/2026 8:58 PM - started thinking of a design for a single leg

i have started designing the main idea for the two motor controlled leg not the motor that will move the leg to the side yet I'm thinking between two different leg designs (pictures later). i like how they look like a normal dogs leg.

the main legs I'm going to design around

2/1/2026 - watched even more videos for designs and math

i watched even more videos to get to know how to do the math of how heavy and tall i can make the quadruped with it still being to hold itself upright. i also started looking into some motors that i can use. I've found some 40kg.cm servos that would allow me to make a pretty tall robotic dog that could even probably hold some things while im walking with it like a water bottle.i think i want it to be 1-2 ft tall and carry 10-15 kgs (30 ish lbs.) and this is the video that taught me about the math of torque ill have to do with the quadruped.

another thing im going to make the leg similar to the one that this youtuber tazer technical has made with some springs to distribute some weight. and with this design it can be pretty tall compared to others

heres the link to the motors
40kg.cm servos
40kg.cm servos

2/14/2026 4 PM - started doing some math and some cad

first im starting with the math so i can see if the motors that im going to get will be strong enough for the robotic dog to lift itself and how heavy i can make the body. this is a drawing that i have made for showing the main design of the leg outline of what ill try to make. i think with using 40 kg.cm motors i can have a main body that is 4 kgs heavy which should be easy to have the bodies weight be under.

i also started making a cad model of the motor hub it'll have holes for threaded inserts just to make sure that the motors can sit in the part well. it will hold three servos two facing out for the main leg movement and one facing perpendicular to pivot the leg outward. the clip things and hole where the servo motors wires are going to hopfully help the wires stay out of the way and hold them all in where they should be safe.

2/14/2026 8 PM - Just found an insane sensor

I found a 360 degree lidar sensor that if I have more budget for the robotic dog I might get so it could map out places and do better object avoidance. Hopefully it will work well here’s the link to it
lidar link

2/15/2026 - CAD modeling for knee joints pretty easy kind of

this is what I've been doing for the past while and it was pretty strait forward other than making sure that all the tolerances for the rotations of the joint are able to move well. i also am thinking that im going to try to find some metal tubes that can be fit into the parts to make better longer lasting joints kind of like these
Spacers

last thing the only hard thing to do was making sure that the parts that are going to tighten onto the carbon fiber rods or wood if i don't have enough budget for carbon fiber rods. for now im going to just slightlu under size the holes to make sure that they fit well.

here are some pictures of the modeled joint