…And we’re back after a long holiday to continue delving into the video record of the evolution of Big Dog and its progeny. This video is a PR piece generated by a meet and greet event whose details are already slipping from my memory, but it does provide some interesting close up views of some of the sensor hardware as well as a snippet of an operator (looks like the “Follow Tight” guy) commanding the robot from a manual controller while walking behind it. This last bit was interesting as an insight on how the robot could be used in a combat situation even if it is not armed; the body itself is heavy enough to absorb incoming small arms and automatic weapons fire, so it might make a good shield for infantry assaulting a defended position, similarly to the way in which soldiers will currently advance behind tanks. Check it out and see what you think:
LS3 in the field
This is a short video that focuses on an interesting part of the LS3 sensing systems: the use of a “shoe tracker” device which is strapped around a soldier’s foot and helps the machine to follow. Apparently, this is not required but approves tracking performance. Also, the sound of the motor seems much louder in this video than in previous ones, although it has a much deeper note than the whiny buzz of Big Dog.
A throwback to Big Dog
OK, this isn’t going to be a blog with a lot of puns, I promise you, but sometimes, I can’t resist a layup like this one. I just noticed this video; found it in an aggregated video, which is not the sort of thing I watch (unless it involves my daughter and I watching cats do stupid things). Not sure how I missed it when it first came out, but it shows what appears to be a design between Big Dog and Alpha Dog in the evolutionary progression, given the angle of the knees and the thinner trunk, so it is out of the chronological order I’m attempting to portray in this series, thus the “punny” title.
The engineering is definitely impressive in terms of the machine’s ability to remain balanced while heaving a cinder block, but also seems more like a curiosity than a viable prototype; I can’t imagine what use this would be put to, other than clearing out moderately heavy debris as part of a pack of disaster recovery robots. Perhaps is was related to preparations for the DARPA robotics challenge? To sum things up here, I guess the best thing to say is, just like a horse, it might not be a good idea to stand directly behind this version of big dog:
Son of Big Dog: Alpha Dog/LS3 (part 3)
More field work with LS3 in this video from the DARPA youtube channel (as opposed to the Boston Dynamics channel, where I generally prefer to get them). This one demonstrates the LS3’s “follow tight” mode which allows it to follow a human operator.
Right off the bat, it seemed like the robot took longer than I would expect to power up; maybe they need to replace those spinning drives with SSDs :). On the plus side, voice control is nice and I was very impressed by how quiet the machine is, especially compared with Big Dog; it didn’t sound too much louder than the noise made by the operator walking through leaves at a normal pace.
In the dry stream bed, it seemed like the stance should have been much wider for more stability, but I expect that there is a good reason for the design choices that were made. The little tumble that the machine takes into the stream is amusing, but there was something that I didn’t notice on my first viewing: the robot rolls right onto a barely visible stationary camera that looked like it was placed slightly downstream to catch a different angle of the crossing; you can even briefly see a team member hop to safety on the right side of the frame. This also explains the way that the scene was cut the way it was: they extricated the camera and moved the robot upstream a bit before filming the “standing up” behavior. I originally thought that there must have been some problem on the first standup attempt that caused them to decide to reshoot, but now I bet that the machine could have stood up and kept going much more quickly. The rest of the video after that is fairly unremarkable, although I found it amusing that the stop sign appeared to be in English and Arabic; check it out for yourself:
Son of Big Dog: Alpha Dog/LS3 (part 2)
Now the LS3 is headed out into the field, exhibiting the following behaviors in this video: climbing a typically rocky forested New England hill, playing “follow the leader” with a human subject through high grass and an open field, double timing it down a dirt road, standing up, and a brief bit of operation with multiple LS3 units. The robot body is more robust than the Alpha Dog prototype from the previous video, with clear evolutionary progression on the side “ribs” that help the robot roll onto its “stomach” when standing up; also, the execution of the “standing up” behavior is smoother and more polished:
Son of Big Dog: Alpha Dog/LS3 (part 1)
One evolutionary branch of the Big Dog family is Alpha Dog, which eventually becomes LS3 (AKA Legged Squad Support System). Here we start to see the transition from a very rough research prototype to a more polished prototype that is capable of participating in field trials with end users.
First we start in the lab, with a video of Alpha Dog being put through its paces. One subtle but informative aspect of this video is the safety features associated with the test area: caution tape to warn humans that they are entering a potentially dangerous area, flashing lights on the robot to indicate that it is in operation and may move unexpectedly, and a heavy gantry to prevent the robot from falling over or exiting the test area in the event of a severe malfunction. Other interesting points to note here are (obviously) the robot’s ability to traverse rough terrain, its impressive “standing up” behavior, and the looting of the Boston Dynamics fitness center (presumably not just to simulate the added weight of a payload but also to adjust the center of mass to correct for asymmetry in the weight distribution of drive components):
Move over Big Dog, here’s Little Dog
After a brief hiatus dealing with router issues we’re back with a new post.
We’ve seen a few videos of Big Dog and now it’s time to meet the rest of the family. This video shows Little Dog being put through his paces climbing over rough terrain. I’m fairly old school, and for some reason this video reminds me of stop motion special effects that were used in movies back in the day. Little Dog also looks (and moves) kind of like a big beetle. Don’t take my word for it, check out the video:
Bring on the cheap Chinese Big Dog knockoffs…
Perhaps not unexpectedly, there is now a cheap-looking Chinese copy of Big Dog. From the extra bars on the side, the lack of any exerpts of complicated recovery from a near fall, and the fact that all kicks and pushes are delivered gingerly, I deduce that the stability is not yet nearly as good as for the original. They do show someone briefly riding, which is kinda cool.
Check it out:
Big Dog’s reflexes
Here’s a video showing Big Dog on rougher terrain, including getting a leg stuck in a cinder block to the amusement of its handler. The movements in the downhill sequence in the forest, remind me very much of horse, except for the part where the legs bend the wrong way:
Introduction to Big Dog
If you are interested in robots, you’ve probably heard about Big Dog. I’m planning to dig up all of the videos related to this fascinating machine, its predecessors and progeny. This video is a great place to start because it shows a fairly advanced prototype with annoying characteristics (i.e. that awful buzzing motor noise that makes you feel like you’re living too close to a motocross track), but also displays characteristics that are more stunningly lifelike than all of those bipedal machines and animatronics that are continually produced. Particularly interesting is the part where it slips on the ice and manages to correct its posture; this is so organic that it feels more like a pratfall from a comedy than a robot demonstration.
Anyway, enough words, here’s the video: