Maker.io main logo

Rock'em Sock'em Robots: Part 2

2023-10-25 | By Zach Hipps

License: See Original Project Arduino

This week I'm continuing work on building my life-size version of Rock'em Sock'em ‎robots. I fully realize how ridiculous this project is, but when has that ever stopped me ‎before? In part one of this project I focused on building and prototyping the punching ‎arm mechanism. If you haven't read that article yet, I would suggest going back and ‎starting there. Now that I have a working prototype, it's time to improve it. 3D printing is ‎an excellent method of making so many things, but when you need parts that are very ‎strong and durable, there's no substitute for metal. The first thing I need to do on the ‎prototype is swap out the 3D-printed brackets for metal ones. These brackets connect ‎the aluminum extrusion to the pillow block bearings. I used an online laser-cutting ‎service to get really precise parts. Once I swapped those out, I immediately felt quite a ‎bit more rigidity in the punching arm mechanism.‎

extrusion_1

extrusion_2

extrusion_3

I'm using aluminum extrusion as a skeleton for each robot. In order to make these look ‎like the original toy, I need to design and print some plastic pieces to attach to the ‎skeleton. This project is quite large, and the pieces I need are larger than a typical 3D ‎print bed can fit. So, I need to decide where to split my model strategically. I feel like ‎there are natural breaks between the upper arm and forearm, as well as between the ‎forearm and fist. The fists are arguably the part of this robot that will take the most ‎beating. They need to be extra strong, so I used an additional outer wall and a dense ‎infill setting on my 3D printer to achieve maximum strength. The forearm and upper ‎arm pieces are not as critical, so I used a standard wall count setting, and decreased ‎the infill setting to save time on these large prints. The reason I chose to use aluminum ‎extrusion for the construction of the skeleton is because of how easy it is to attach ‎things to it. I used M5 bolts and t-nuts that slid into the slots to attach the arm pieces. ‎Should any of these pieces get destroyed in battle, they are simple enough to remove ‎and replace with newly printed parts.‎

print_4

print_5

print_6

print_7

print_8

Now that I'm done with designing and assembling the arm pieces this is starting to look ‎like the original toy! It's time to move on to the robot head. One of the reasons this robot ‎toy is so iconic is because of its blocky design aesthetic. The thing looks like it was ‎built out of steel I-beams assembled together with industrial scrap. It has hemispherical ‎rivets all over the head and body pieces. I really like the look and design of this toy, so I ‎wanted to get my 3D model right. I used a set of calipers to measure details like the ‎eyebrows and nose and spent quite a bit of time modeling the head of the robot. The ‎head will get attached to a pneumatic cylinder so I also modeled a square slot in the ‎center of the head. A short length of 2020 aluminum extrusion slides into the slot. This ‎is so that I have something solid to thread the pneumatic cylinder into. Now that the ‎head is attached to the robot skeleton, this project is really starting to take shape!‎

attached_9

attached_10

Right now, the pneumatic cylinders are not connected to anything. I need to run some ‎‎6mm tubing to the two ports on each cylinder. I sort of got lucky with the diameter of the ‎pneumatic tube because it fits perfectly within the slots of the aluminum extrusion. I ‎designed some clever little clips that hold the tube tight in the slots. Once I had the ‎tubes run to each cylinder, I cleaned things up using some cable ties. The other ends ‎of the tubes need to be connected to the solenoid valves. This project will have six ‎pneumatic cylinders total, which means I need six solenoid valves to actuate the ‎cylinders. I decided to have a central air supply manifold to distribute air to each ‎pneumatic solenoid valve. I was careful to use Teflon tape to ensure better seals on ‎each threaded joint. I also used some quick connections between the solenoid valves ‎and the manifold in case I need to do any maintenance or move things around. Even ‎though I was diligent with the Teflon tape, some soapy water revealed several leaks in ‎the system. I spent a bit of time trying to reduce and eliminate those leaks the best I ‎could.‎

leaks_11

leaks_12

leaks_13

leaks_14

leaks_15

The final step for this portion of the project is to make a control circuit board for all the ‎electronic components. The solenoid valves require a 12V supply, so I soldered a ‎barrel jack connector onto a solderable perforated breadboard. Then I added some ‎terminal blocks so that I could easily connect and disconnect the solenoids to the PCB. ‎The positive terminal of each solenoid valve was connected directly to 12V, while the ‎negative terminal was connected to ground in series with an arcade button. Eventually, ‎this PCB will have a microcontroller, but for now, I'm controlling the valves directly with ‎the arcade buttons. When the button connects the negative terminal to ground, the ‎solenoid valve is actuated.‎

step_16

step_17

step_18

I connected everything up to the PCB and plugged it into the power supply. My face ‎totally lit up as I pressed the arcade buttons and watched the giant robot arms spring to ‎life! There was something that I added since completing part one of this project. I ‎inserted some air flow control valves in series with each branch of the air supply. ‎These valves let me fine-tune how fast the air is delivered to each pneumatic cylinder. ‎If the arms are too forceful, I can dial back the air supply, making them slightly less ‎terrifying. Safety is a legitimate concern here because if one of these arms were to hit ‎me it would definitely leave a mark! I still have a lot to do on this project. I need to ‎design and assemble the torso for the robot. It will have a 9 DOF IMU to detect punches. ‎A microcontroller will keep track of how much damage the robot is sustaining and will ‎display a life meter using an LED bar. As the robot sustains more hits from its opponent, ‎the life meter will slowly drop to zero. When it hits zero the head will pop up indicating ‎a knockout! Oh and of course I need two of these robots so I will have to build another ‎complete setup. Stay tuned for more updates and let me know what you think of this ‎project.‎

connect_19

connect_20

connect_21

 

 

制造商零件编号 GST60A12-P1J
AC/DC DESKTOP ADAPTER 12V 60W
MEAN WELL USA Inc.
¥151.41
Details
制造商零件编号 721AFMS
DC POWER JACK, SHIELDED, FRONT P
Switchcraft Inc.
¥59.99
Details
制造商零件编号 1725656
TERM BLK 2P SIDE ENT 2.54MM PCB
Phoenix Contact
¥13.51
Details
制造商零件编号 4754
ADAFRUIT 9-DOF ORIENTATION IMU F
Adafruit Industries LLC
¥210.22
Details
制造商零件编号 102010268
SEEEDUINO NANO
Seeed Technology Co., Ltd
¥61.86
Details
制造商零件编号 INND-TS56RAB
DISPLAY 7SEG 0.56" SGL RED 10DIP
Inolux
¥11.04
Details
Add all DigiKey Parts to Cart
TechForum

Have questions or comments? Continue the conversation on TechForum, DigiKey's online community and technical resource.

Visit TechForum