We should use this amazing mechanism that's inside a grasshopper leg

Also, the hinge from an overhead cabinet! That's like the last mechanism too. The sponsor is Incogni: Take your personal data back with Incogni. Use code SCIENCE at the link below and get 60% off an annual plan: incogni.com/science

This video is all about storing energy slowly and using it quickly, but there might be interesting instances of the opposite as well. For example, when winding a mechanical clock, you are storing energy quickly and then using it slowly. The purpose there is to allow the energy to be released over the coming week so that you don't need to apply energy continuously to keep it going.

The linkage you are thinking of is called an over-center mechanism and they are used everywhere! Some common examples would be vice grip pliers, toggle latches, and clamps.

15:06 "...your arm is QUIVERING holding the bow at full draw." Good one.

Ballistic Seed Dispersal (ballochory) - cress pods, touch-me-nots and others, tension is stored in a 'just barely stable" state in the pod wall, the smallest disturbance tips the balance and a huge elastic release of force expels the seeds.

Mantis shrimp: offended

The last mechanism reminds me of staplers -- when you open them up to refill them, there is a similar mechanism with a hinge and a spring.

I love how for the example of a catapult you used a trebuchet, the superior siege engine.

Here in Western Australia we have the "trigger plant". Evolved to trap insects for pollination or some species for consumption. The stamen and style of the flower are fused into a column, which can look like a club. The column is slowly pulled back under the flower and "locks in place, when a insect lands on the flower and touches the trigger hairs the column is released and strikes the insect where it is stunned and releases previously collected pollen for fertilization or trapped to be slowly dissolved for food. The strike is one of the fastest movements in the plant kingdom, taking as little as 15 milliseconds.

Hi Steve. An example of the mechanism you showed can be found in the human body. The "tensor fascia lata" originates from the pelvic bone "the iliac crest" and inserts onto the outer side of the knee. It is a long thick fascial structure that is tightened by a small muscle originating from the pelvis called "the tensor fascia lata". This muscle's function is intriguing, as it spans and controls two major joints -the hip and the knee-, and operates as a joint extensor when these joints are in extension, and a flexor when these joints are at 20 degrees or more of flexion. It effectively operates as a locking mechanism for the hip and knee to allow us to stand without having the spend too much energy through the major muscles -glutes and quads-. Its resistance to motion follows the same pattern of change that you highlighted in your hinged joint with an elastic band, and is least effective at 20 degrees of flexion.

I noticed as a kid the best way to catch a grasshopper was to get it right after it landed, as it seemed to take a second or two to get itself ready to jump again. It would then jump half cocked, only going a short distance, making the follow up quite easy.

You are such a good science communicator. Even for someone who knows a bit of "everything," you make me grasp basic concepts that I've had a hard time wrapping my head around since forever. Sometimes, learning things is all about having the right teacher, because that can literally change the way you think about things. Nothing better than getting that tingle in your mind when you suddenly truly grok something you've struggled with, or just understand by rote memorisation.

There's a window-breaking tool that does that sort of thing. My mate had one years ago. It's a heavy, cylindrical metal device with a moving spike inside like a plumb-line weight. You push the pin back harder and harder, then it suddenly juts out with a force sufficient to easily break toughened glass.

Okay so never in my entire life have I been able to snap my fingers due to inadequate explanations of what I'm supposed to even be doing and then at the age of 42 a single Steve Mould explanation has me doing it first time. What a world we live in.

The hinge mechanism shown around the 12 minute mark is quite similar to a motorcycle kickstand. It uses a fairly strong spring to keep it in the upright position, as you wouldn't want it coming down while riding. But pushing the kickstand down will eventually find a new stable position where it will stay down all on its own, but give it a little tap backwards and it will release and swing all the way to its upright position. And of course when fully down its actually canted forwards so the weight of the bike also holds it in place securely. Also, I'm glad you mentioned clicking or snapping your fingers. That was on my mind for some time there, lol

what i like about this channel is how succinctly the information is delivered without any of the pretentiousness that this type of channel always have. he presents the information extremely smoothly and coherently without trying to make himself the star of the show and that's a quality i sincerely can only wish to strive for...

i hope you continue to make successful, non click bait, videos like these for decades

Says calling it a catapult would be confusing and shows a trebuchet. 🤔

"[...] For example, the soft living actuator of a Venus flytrap leaf (Figure 1A) has two stable equilibrium states, namely, an open convex shape (one stable state) and a closing concave shape (the other stable state). It can switch rapidly between these two stable shapes to achieve fast closure in about 100 ms.[53, 54] It utilizes the so-called bistable snap-through in engineering.[55] Similar bistability is observed in hummingbirds for rapid beak closure in a few milliseconds to eat flying insects (Figure 1B),[56] in the earwig wings to fold and lock their wings[57] (Figure 1C) [...]" - Chi, Y., Li, Y., Zhao, Y., Hong, Y., Tang, Y., & Yin, J. (2022). Bistable and Multistable Actuators for Soft Robots: Structures, Materials, and Functionalities. Advanced Materials, 34(19), 2110384.

Astonishing design. Thank you for the complicated- but- understandable explanation!