221–230 of 230 posts
Earlier quoted context omitted.
Drives me crazy that if I suggest diagrams like this might be useful on wikipedia or documentation I mostly get downvoted into oblivion.
I'm sure a lot of users on HN are angry that this site requires JavaScript and demand it to be accessible on a text based browser.
And of course the logical next step: https://anderspitman.net/19/#netcatable
Earlier quoted context omitted.
Well do you mean the motor controller, the control computer, or the remote control? I’ve got some info on the motor controllers I’m using: https://reboot.love/t/vesc-mods-for-robotics-use/ The control computer is a raspberry pi running python. It looks like I’ve not committed the code in a while, but this repo may be helpful: https://github.com/tlalexander/rover_control Though for the above, I’ve recently found that…
Oh huh, that's pretty involved, thanks. Can I ask why you rolled your own instead of using off the shelf RC components, like what is used in RC cars, for example? For the remote control and ESC, at least, it seems like it would be simpler.
For the ESC it’s more complicated. The VESC is off the shelf, but it has a feature most ESCs don’t. The VESC supports encoders. The use of an encoder is very important to get full motor torque on the brushless motors even at zero velocity. This allows Rover to slow down or stop even on a slope. The encoder is also used for precise velocity control, which keeps all the wheels spinning in concert. Additionally, the encoder data is sent up the CAN bus to the raspberry pi so my program knows wheel velocities.
You could certainly build a rover without encoders and with a regular ESC, but it may have trouble starting from a standstill and it may not always drive in a straight line if the wheel velocities are not all the same. Another thing to note is that if you spin the motors really fast you’d probably melt the gearboxes. I’m moving the motors pretty slowly compared to their maximum speed. But a regular ESC might work fine! I’ve not tried it.
Earlier quoted context omitted.
PETG. Specifically it would either be Hatchbox PETG or PushPlastic PETG.
I'm very new into 3D printing scene, so far only been printed with PLA. Also have some ideas that includes some motorised parts with gears. Do you think PLA is a bad choice for this?
PLA is fine to start with though. If you see failures you can switch.
I really like this presentation! It’s wonderful. I don’t mean to hijack but I thought this would be an appropriate place to share a photo album of the 3D printed planetary gears in my open source robot: https://imgur.com/gallery/GqXD2Zj I’ve been 3D printing gears for some years now and I want to spread the word that 3D printed gears actually work really well! The gears in the image album above have been operating on…
Hey, nice project :) A few friends were experimenting with 3D-printed gears for their robots, I've advised to switch to helical gears as these should make less noise, and less prone to wear (since the load never happens on a single teeth, but is transfered progressively). Of course, that creates axial load, which might or might not be an issue (and countered with a second cog), and complexify assembly, especially for…
Earlier quoted context omitted.
Oh huh, that's pretty involved, thanks. Can I ask why you rolled your own instead of using off the shelf RC components, like what is used in RC cars, for example? For the remote control and ESC, at least, it seems like it would be simpler.
Well for the remote control, I already had the one I used. I started a wireless electronics company in 2013 (and eventually failed), so it’s a point of pride to use my own remote. But any RC remote would work. For the ESC it’s more complicated. The VESC is off the shelf, but it has a feature most ESCs don’t. The VESC supports encoders. The use of an encoder is very important to get full motor torque on the brushless…
Earlier quoted context omitted.
Not to dismiss your work, but do you think the best investment of your time is to write another textbook (assuming this is an undergraduate level book in a relatively well-explored field), or in adding detail/great illustrations/great interactive charts to an existing work? I know (really, like, I know ) how detrimental this would be to anyone's career, and I'm not saying this as a moral condemnation of what you're d…
I'm writing a textbook on a topic no existing book covers: the internals of a web browser. For your broader question---I understand what you're saying, but it's very difficult to edit someone else's writing. That's where "committee voice" comes from: it's the lowest common denominator to multiple authors working together. And often how I visualize things comes from how I look at things, and coming up with a visualiza…
And I see what you're saying on how it's hard to build on someone else's work, and how what is relevant to illustrate heavily depends on the viewpoint of the author. Still I can't shake the feeling that there is so much duplication. Maybe I should just look at differently. Anyway, thanks for weighing in.
Earlier quoted context omitted.
Curious: does something not work for you? If so, what platform are you using? Asking because it works perfectly for me on mobile...
I was on a Chromebook with a touchscreen. Maybe you do "platform detection" and don't register touch handlers on laptops. I haven't looked at your code (I didn't see a repository link and I didn't bother looking further). Cheers on the cool demos, I think it could be the start of a great resource for elementary school teachers introducing machines. I know this sort of thing would have been great when I was in grade 3…
Earlier quoted context omitted.
> Still, after finishing the article, I'm impressed by not just the the number visualizations, but by their legibility and smoothness I think the author probably had to try a lot of things before hitting on such a well-balanced set of visualizations: not too much detail, not too little, not too many degrees of freedom, not too few, usable on hand computers, usable on laptops. But I think that if you gave someone the…
I'm with you that there can be an illusion of fluency, but I don't think that casts any doubt on the value of the article. Most people will read it and say "fun" (including me, since I don't work with gears) and maybe 5-10% will go on to do something else with it, but that's working as intended. I agree you can't really say you know something without testing the knowledge. You need to do more work to test whether you…