Sorry, I should have clarified I meant robots with per joint electric motors + reduction gearing. almost all of Atlas’ joints aside from a few near the wrists are hydraulic which I suspect is key to agility at human scale.
A lot of people look at progress in robotics in terms like “humanoid robots getting better over time” but a robotic arm using modern electric motors and strain wave gears is, in terms of technological progress, a lot closer to Boston Dynamics’s Atlas robot than an early humanoid robot.
I would argue that the current Atlas robot looks a lot more like the earlier hardiman robots than it does a modern factory robot arm. The hydraulic actuators are more sophisticated (efficient) and the control system actually works but that’s it.
Contrast the six axis arm which has a servomotor+gearing per axis. Aside from using a BLDC motor to drive the pump, and small ones for the control valves, Atlas is almost purely hydraulic. If the Hardiman Engineers were around today Atlas seems like a logical successor.
Perhaps you think Atlas is using one motor per joint (It would be hard to fit 24 in the torso) or ganged variable displacement pumps in which case there would be more similarities. IMO there aren’t enough hydraulic lines for that. Still of the 28 joints in atlas only 4 are what you’d find in a conventional robot arm (the ones closest to the wrist)
Again, strain wave gearing (as an approach, including electric motors with high specific power) is lighter than using hydraulics, overall. The same is true for planetary roller screws. This is true regardless of scale. Hydraulics are used for other reasons than maximum performance physically achievable.
Boston Dynamics decreased the weight of their hydraulics system by 3d printing hydraulic channels in the skeleton. That’s expensive, and planetary roller screws are still better if done properly.
Sorry, I should have clarified I meant robots with per joint electric motors + reduction gearing. almost all of Atlas’ joints aside from a few near the wrists are hydraulic which I suspect is key to agility at human scale.
Inside the lab: How does Atlas work?(T=120s)
Here’s the knee joint springing a leak. Note the two jets of fluid. Strong suspicion this indicates small fluid reservoir size.
I’m getting the impression you didn’t read what I wrote.
Hopefully it helps to get back to the source material Articulated Robot Progress
I apologize if I’m missing anything.
I would argue that the current Atlas robot looks a lot more like the earlier hardiman robots than it does a modern factory robot arm. The hydraulic actuators are more sophisticated (efficient) and the control system actually works but that’s it.
Contrast the six axis arm which has a servomotor+gearing per axis. Aside from using a BLDC motor to drive the pump, and small ones for the control valves, Atlas is almost purely hydraulic. If the Hardiman Engineers were around today Atlas seems like a logical successor.
Perhaps you think Atlas is using one motor per joint (It would be hard to fit 24 in the torso) or ganged variable displacement pumps in which case there would be more similarities. IMO there aren’t enough hydraulic lines for that. Still of the 28 joints in atlas only 4 are what you’d find in a conventional robot arm (the ones closest to the wrist)
Predictively Adjustable Hydraulic Pressure Rails
The patents coming out of BDI suggest they’re not doing that and this is closer to Hardiman than it is a modern factory robot arm.
Again, strain wave gearing (as an approach, including electric motors with high specific power) is lighter than using hydraulics, overall. The same is true for planetary roller screws. This is true regardless of scale. Hydraulics are used for other reasons than maximum performance physically achievable.
Boston Dynamics decreased the weight of their hydraulics system by 3d printing hydraulic channels in the skeleton. That’s expensive, and planetary roller screws are still better if done properly.