21–30 of 84 posts
Great, but that robot isn't doing an actual task? I sort of struggle to see how getting good positioning accuracy from a high backlash system under zero load can have a useful application. Maybe just lack of imagination on my part. There is this trend that says make and buy bad hardware, the software will solve it. I haven't noticed that paying off. Tesla using webcams for self driving is an example. Boeing designing…
I've seen in the past a different trick that is adding an IMU[1] to the robot arm. When combining two different types of sensors, it's called Sensor Fusion[2], and it's really common to put together a IMU with GPS and slap a Kalman Filter[3] for very accurate position reading. The particularly cool thing of this video though is that they could mount the new sensor within the motor itself, making it all a lot more com…
You can’t judge backlash by how the robot repeats the exact same set of movements over and over. That removes hysteresis from the problem definitionally.
I'm not a fan of the youtube link trend on HN, as cool as the latest robots are. I know they're encroaching on territory previously held by much heavier additive and subtractive machines.
Earlier quoted context omitted.
You have oversimplified the Boeing one: their goal was to create an efficient plane to compete with Airbus without needing the expense and delays of a new type certification. To do this they needed bigger engines on the same frame, which in turn needed to be mounted further forward affecting flight characteristics and requiring retraining. Retraining would be a sales killer so they hacked on some software systems to…
Wasn’t the Boeing issue completely preventable with an inconsequential extra part that cost nothing? Like the short cuts actually worked but they literally went all the way to almost succeeding and snatched defeat from the jaws of victory. (Aside from all the other things they did that also contributed to disaster situations going worse)
Whereas maybe before on older planes you get in a stall and you nose down to reduce AoA. You don't need a sensor to know this look at altitude etc.
So now you need perfect ten nines of reliability AoA sensors. Their use case has gone from a data point to mission critical, but the sensor is the same.
Earlier quoted context omitted.
You have oversimplified the Boeing one: their goal was to create an efficient plane to compete with Airbus without needing the expense and delays of a new type certification. To do this they needed bigger engines on the same frame, which in turn needed to be mounted further forward affecting flight characteristics and requiring retraining. Retraining would be a sales killer so they hacked on some software systems to…
There’s some really negligent stuff, like changing how to disable auto pilot (ie, MCAS) — as the pilots of both crashed planes attempted actions that would have disabled the autopilot on previous models.
How do 3 axis robots you can buy for 100$ (3D printers) have a static accuracy of 0.05mm? It's not control theory, but mechanics and steppers.
It’s the compromise between a gantry vs arm design
I'm not a fan of the youtube link trend on HN, as cool as the latest robots are. I know they're encroaching on territory previously held by much heavier additive and subtractive machines.
And I am okay with YouTube when a video makes sense, but in this case they have basically crammed a short article into a video, making it more awkward to read: slides with texts and diagrams, with some background music, and only a video demonstration in the end.
Great, but that robot isn't doing an actual task? I sort of struggle to see how getting good positioning accuracy from a high backlash system under zero load can have a useful application. Maybe just lack of imagination on my part. There is this trend that says make and buy bad hardware, the software will solve it. I haven't noticed that paying off. Tesla using webcams for self driving is an example. Boeing designing…
Look at this later videos where he has the servo lift a weight on a long arm.
One example of real work: https://www.youtube.com/watch?v=GCHXNcpq3OA
Earlier quoted context omitted.
Wasn’t the Boeing issue completely preventable with an inconsequential extra part that cost nothing? Like the short cuts actually worked but they literally went all the way to almost succeeding and snatched defeat from the jaws of victory. (Aside from all the other things they did that also contributed to disaster situations going worse)
I don't know. Maybe an expert can chime in but I think it is a hard problem because of ice etc. I think the 737Max has the problem where AoA matters more because you can get into a stall you can't get out of. Whereas maybe before on older planes you get in a stall and you nose down to reduce AoA. You don't need a sensor to know this look at altitude etc. So now you need perfect ten nines of reliability AoA sensors. T…
Chances are, if your AoA is anywhere near the critical AoA, a competent pilot is likely aware of it. The sensors are just another safety factor on top of that to help ensure situational awareness.