FYI to all those waiting for the hexapod prototype hardware - the body panels are in production and we’ll ship them as soon as we have all parts at our warehouse in Canada. Sorry again for the delay.
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Hi All,
Got a little issue with file size for attachments here that’s been resolved today.
Attached is the actual assembly in STEP file.
SESV2-LSS-HEX-2020-03-17.zip (8.1 MB)
Our apologies, but still waiting for the top and bottom body panels before we ship the full hardware.
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No hurry, hope everyone is doing well there and staying safe!
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We’re doing are best and it seems to be working for most of us!
Maybe this is what we’re missing:
I definitely want a surrogate! I am starting to get shack wacky.
(I’m a home body, I can’t imagine how my wife or other extroverts feel. Also, I want my surrogate to look like Bruce Willis too)
I’ve been working diligently on Robot IK and Dynamics within ROS2. Firstly, it’s been a really tough road the last 2 months getting this dog-crap (i.e. my code) working only to discover my URDF file I exported from SolidWorks way back in December had the joint coordinate systems completely randomized…XYZ unit vectors were all over the place. No wonder when I entered coordinates or orientations for end-effectors they would be all twisted and wrong. lol. I had to go back and redo the URDF but now all is right in the (cartesian) world.
So I heavily refactored my code into something clean and friendlier. I now have stuff separated into State objects and the physics-of-motion models, and visual renders that act on states. Now current state and target state are just 2 sides of the same coin and I can render states as ghost-mesh models with indicators within RViz2. RViz is actually quite flexible. I’ve figured out how to add manipulators for end-effectors or what-not and context menus. In the video I have one to control the robot standing height. My node is also doing proper gravity compensation on the compliant joints and predicting torque current draw very accurately. Robot Dynamics node can handle any number of legs so looking forward to trying out on the Hexapod as well.
Robot is still shaky since I have no PID or trajectory smoothing, so that is my next task.
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Really liking the progress Colin! Thank you for sharing here.
On another note, the body panels have arrived, but still waiting for a few additional products before we can create the kits to ship.
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Good to hear about the hexapod. I am coding to support both biped and hex (or quad) and my latest refactor got rid of the last 2-leg specific code, so I look forward to testing on the hex too.
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@kurte @xan @zenta Greatly apologize for the delay in sending the hardware, but you should have each received a confirmation for a RobotShop order for the parts. Keep us posted when you receive the packages! As discussed, it’s up to each of you to include whatever MCU or SBC you’re most comfortable starting with (and wiring it), as well as the battery (XT60 connector is best). Arduino and/or ROS (running on a Pi) are best.
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Sounds great. Thanks!
Hope everyone is safe and doing well.
It will likely be a few days after I receive the package before I will feel safe to do much with it. Yes I know maybe a bit paranoid, but I prefer to be safe than sorry.
Side note: The new Teensy 4.1 is officially starting a quick beta… There is a thread over on PJRC forum talking about it.
Again hope everyone is well
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New video posted with new Trajectory Planning working! This worked out awesome! Also demoing calculation of convex hull and support polygons for limb/feet contacts. Next up…make those trajectories multi-point and add end-effector manipulators to RViz for creating the planning steps.
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Since it is related to the topic, I would like to share with you my work on my robot dog: https://community.robotshop.com/forum/t/mechdog-robot-dog-based-on-arduino-and-lss/65705
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Impressive! Very much appreciate that you’re making it more universal for other types of robots.
Excellent! Curious to know how long it takes you to assemble it (including basic wiring).
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Is there a reason for why the body panels are missing in the package?
I can make my own, but I thought it was meant we should all share the same hardware at first.
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That seems to be an oversight on our part. Creating the order now so it gets to you quickly. Apologies.
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I was wondering as mine arrived in town yesterday, but picked up early from PMB (~6AM) and did the first pass at quarantining the parts… And wondered why yesterday there was another logical order…
Looks like time to assemble one of the Teensy boards.
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I’ve got my package yesterday! Love the premium boxes for the servos!
After receiving I started spreading out the components and wondered what happened with the body and controller board. Seems that I missed out on some messages here… 
By what I could inspect now is that I like the improvements done on the servos and brackets. The ball bearing on the servo, a huge amount of mounting holes, bus communication: Love it! And the cable clips are a brilliant idea! Sorry for my excitement. I was not able to do anything robotic related so I’m pretty excited! Can’t wait to start 
Anyway, @zenta, @kurte, Did you decide on what board to use? I think it will be beneficial if we can share code so I will go with whatever you have.
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Hi @xan and @zenta (and others) - I will hopefully have a chance to play some with the servos in the next day or two… Giving them some time to air out… Sorry I know I am being paranoid, but…
I am planning on over time hopefully work with the hexapod a couple of different ways electronically.
For the first round, I am probably going to use a Teensy. Probably first round I will do with a Teensy 4.1… Which is in beta now, but by the beta rules, I can not show any pictures… More details about it up on PJRC forum thread (https://forum.pjrc.com/threads/60532-Teensy-4-1-Beta-Test)
I have two boards sitting here that I did a quick and dirty design for, that I need to get going on soldering them up… Although at first I could simply use any T4.x and use the adapter board, to do the conversion to 5v for Serial ports.
The simpler version looks sort of like:
I believe almost all Teensy boards would work with this one, I would need to double check, but would probably use either T3.6 or T4.1 (or T4 with a castellated solder on board FRDM4236 which gives the T4 the same footprint as T3.6 or T4.1…
But with T4.1 or 3.6 the 5 pins can be hooked up for USB Host code… Where I probably will use a PS3 controller to start off with. I like PS4s better but mine appears to have a dead battery. Can use several different ones by plugging BT into USB…
Edit: If I remember correctly the yellow pins are setup with Arduino shield spacing so one could plug in something like an XBee shield.
Again is like the previous one mentioned, but was adapted from a board that supports Robotis Dynamixel Servos. A sort of nice feature of this one is that I have IO pins in place to allow me to plug in an Adafruit ST7735 or ST7789 display right below the speaker and would probably use the small ST7789 display (I have a couple of them)…
Longer term, will probably want to try moving to ROS (probably ROS2). Probably use RPI4. Maybe use UP board or Odroid ?
Or we could all have some fun and try one of the NVIDIA boards like:
Although I don’t know if they are supported by ROS, but might be great for any image processing one might want to do.
But first I should work on walking before trying to run!
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