Technology and life: starting with solar cars

Chapter 110

There is a spring between the mechanical finger and the mechanical finger to spread the finger, that is to say, the function of the spring is to give a tension between the fingers, and at the same time fix the lower part of the mechanical finger, and the upper part is movable to make it Robotic fingers can perform bending movements.For example, if a spring is installed between the first knuckle and the second knuckle of the mechanical index finger, in order to make the first knuckle of the mechanical index finger bend to 135 degrees to the second knuckle At this time, it is necessary to add an area where the first knuckle and the second knuckle are connected.And this extra area is used for stretching, so that the stretched knuckles do not leak out of the inner area of ​​the nail.

In order to prevent the index finger from falling off between the first knuckle and the second knuckle, a block should be added between the area where the first nail protrudes and the second knuckle.This tab is located at the beginning of the second knuckle, and the other tab is located on the extra area of ​​​​the first knuckle.When the first knuckle moves continuously until it forms an angle of 135 degrees with the second nail, the two blocking pieces will be stuck together to prevent the first knuckle from falling off.In order to better adjust the first knuckle so that it will not sway during the bending process, a rectangular small iron piece that can be pressed and contracted can be added to the baffle of the extra area of ​​the first knuckle , the purpose of this iron piece is to create friction with the inside of the second knuckle, so as to avoid direct bending too fast when the wire rope is loosened. In fact, it is through this small shrinking iron piece that the first knuckle and the second The friction between the two knuckles reduces the speed of the first knuckle's movement, which can better control the speed of the first knuckle's bending.

To put it bluntly, it is to add various limiting tools to the first knuckle. The first limitation is to add one more piece to the first knuckle, so that the inside of the knuckle will not be exposed after the first knuckle is bent.The second restriction is to add a retractable small iron piece to the back of the first knuckle, and this small iron piece always gives an upward force to the second knuckle, so that the first knuckle and the second knuckle There is an elastic force or friction force between the two knuckles. With this friction force, a direct bending speed can be better controlled, so that the first knuckle can make various shapes.

But at present, the design of the first knuckle Liu Yun intends to only give one state, that is, a 135-degree bend, and the state of being level with the palm.The second knuckle can have a state of 135 degrees relative to the first knuckle, and there is also a state of 180 degrees, and of course there is a state of natural straightening.The maximum angle between the second mechanical knuckle and the third mechanical knuckle can be 180 degrees, because this angle can be up to 135 degrees, so we can subdivide the excess of [-] degrees to [-] degrees , for example, [-] degrees is the initial state of the second knuckle of the mechanical finger, [-] degrees is the state in the middle of the second knuckle of the mechanical finger, it is considered an excessive state, and the state of the second knuckle of the mechanical finger is [-] degrees, It is also the final state. At this time, the second knuckle is perpendicular to the third knuckle, presenting a ninety-degree state.The third knuckle of the mechanical finger is the connected mechanical palm. Although the mechanical finger is a connected mechanical palm at this time, it is not much different from the second knuckle in terms of state. The ninety-degree angle still divides the third knuckle of the mechanical finger into three states according to the reason that the knuckles can be at a maximum of ninety degrees with the robotic palm.

The first state is the position where the knuckles and the mechanical palm are at the level, the second state is the state where the knuckles and the mechanical palm are at 135 degrees, this state is considered an excessive state, and the third state is that the knuckles and the mechanical palm are at [-] degrees degree angle.

In fact, except for the thumb, the other four fingers are in the same state. The second knuckle and the third knuckle can be divided into the initial state of 180 degrees, the transition state of 135 degrees, and 180 degrees. this final state.The first knuckle has only the initial state of 135 degrees and the final state of [-] degrees.

So why is the thumb different from the other four fingers?That's because the thumb of the human body has only two knuckles, which is obviously different from the other four fingers.Therefore, the thumb must be different from the other four fingers in the design of the state, or it can perfectly restore the fingers and palm of the human body.

According to observation, we can know that the thumb has two knuckles, the maximum angle between the first knuckle and the second knuckle is 135 degrees, and the maximum angle between the second knuckle and the palm is [-] degrees. Bar.Therefore, when setting the angle for the thumb, it should be different from the other four fingers, and design the state for the thumb separately.

Still the same as before, if the knuckles can reach 135 degrees of bending, give an initial state directly, a transition state of 135 degrees, and a final state of 180 degrees.If the bending degree of the knuckle can only reach 135 degrees, then only two states are given directly, an initial state of [-] degrees, and a final state of [-] degrees.Now that we have observed the state of the thumb, we can design a state that is different from other mechanical fingers based on the state of the thumb.

At this time, we design the thumb like the other four fingers. First, connect a [-]-degree piece behind the first joint of the mechanical thumb. There is a retractable stop behind the iron piece. , this block can not only be buckled together with the second knuckle, but can even give a force to the inside of the second knuckle, so that the bending of the first knuckle is not so fast, and it is convenient to control the first knuckle the bending speed.Because it is a simulation of the thumb, the extra piece of the first knuckle and the first knuckle are in a state of ninety degrees, so the first knuckle and the second knuckle can only show more than ninety degrees. degree status.

Why can't it show a 90-degree angle? That's because there is a block at the end of the first knuckle, and there is a gap between this block and the second knuckle, so the first knuckle will never be able to It shows a state of 90 degrees relative to the second knuckle. At this time, it is only necessary to change the angle of the extended iron piece behind the first knuckle.For example, the final angle between the block and the second knuckle is 3 degrees, then only need to make the angle between the first knuckle and the extension iron piece is 90 degrees - 3 degrees equals 87 degrees to achieve the first knuckle relative to A 90-degree angle to the second knuckle.

(End of this chapter)