Technology and life: starting with solar cars

Chapter 111

The second knuckle and the first knuckle adopt the same design. Anyway, it can be designed according to the three states of 180 degrees, 135 degrees and 90 degrees. There is no need to make additional designs, it is very simple.

After the flexible design of the fingers is completed, we will design the wire rope. We can completely connect the upper part of the knuckles with the wire rope to the upper part or the lower part of each knuckle, as long as the knuckles can be stretched and bent to 180° It is not difficult. Anyway, it is necessary to design the stretching angle of the wire rope according to the specific situation. There is no specific point, as long as the stretching points of the left and right mechanical palms are basically the same. After all, mass production is required. , if the data is not unified, whether it is an after-sales problem or a parameter problem, it will become very troublesome. The premise of mass production is that the data is the same, that is, the left manipulator and the right manipulator need to use the same mold for manufacturing, and the produced The left manipulator and the right manipulator must remain symmetrical, so that they can be mass-produced in the future.

Not only the position of the wire rope of the finger needs to be fixed, but also the mass production of the mechanical palm can make the parameters of each palm basically consistent, which is convenient for replacement and maintenance.The position of the wire rope is fixed, the shape of the mechanical palm is fixed, and the parameters of the spring need to be fixed. There is no doubt that the parameters of the spring in each finger are different, so the parameters of the spring in each finger must be measured and recorded. And setting, when the spring parameters in the finger are tested, record this data, and then mass-produce each spring, and mark the number of 1-1 on the spring to identify which finger joint the spring is in. The first 1 of 1-1 represents the thumb, if it is 2-1, it represents the index finger, 3-1 represents the middle finger, 4-1 represents the ring finger, and 5-1 represents the little finger. The second 1 of 1-1 represents the first knuckle of the thumb, and if it is 1-2, it represents the second knuckle of the thumb.If it is 2-3, it represents the third knuckle of the index finger, and so on.In this way, the user, that is, the operator of the mecha, can replace the damaged parts by himself, which is very convenient, saves the cost of maintenance, and makes more use of the promotion of the mecha.

Let's talk about the design of the legs of the mecha after the palm and fingers of the mecha are designed.Originally, Liu Yun planned to make the mecha 1.0 use rollers under the mecha to simulate the movement of the human body, but now Liu Yun has changed his mind. Liu Yun intends to make the mecha 1.0 walk like a human in one step. That is to say, without the rollers under the mecha, let the mecha 1.0 lift up its thigh like a human walks, and then put down the thigh, and then move the left leg after the advancement of the right leg is completed.The way forward of the left leg is the same as that of the right leg. The position of the thigh is lifted first, and then the lower leg naturally swings back to a horizontal position according to the effect of inertia. At this time, the thigh slowly falls to the ground. Only completed one leg movement.If the right leg of the mech is the first to move, after the thigh of the right leg of the mech is lifted, the calf of the right leg starts to rotate under the action of gravity to make itself in a vertical position. At this time, the thigh slowly falls, First of all, the calf must be on the ground. After landing, the calf and thigh gradually change from an angle to 180 degrees. When the calf and thigh present an angle of 180 degrees, in fact, the entire right leg at this time is just the thigh and calf On the same straight line, the entire right leg is not perpendicular to the ground.At this time, a sensing device is needed to sense the position of the entire right leg. When it is detected that the entire right leg is at an obtuse angle with the horizontal plane, the control center controls the gear at the mechanical ankle to move the angle of the entire right leg slowly. Wait until the entire lowered right leg is in a vertical horizontal plane before continuing to move the left foot.

At this time, the position of the right leg is perpendicular to the entire horizontal plane. At this time, the joint between the thigh and the calf of the right leg should be locked to prevent the thigh and thigh from slipping.When the thigh and calf of the right leg are locked, start to move the left leg of the mech with the entire right leg as support.After the position of the right leg is fixed, lift the thigh of the left leg.

At this time, it is necessary to control the mechanical thigh. This control can still be handled by stretching the wire rope, or it can be handled by the gear method. Since this place requires a relatively large force, Liu Yun plans to use it on the thigh. Gears are used to control the lifting of the thighs of the mecha. According to the required footsteps, the angle of the thighs can be set to 30 degrees, 45 degrees and 90 degrees. When the angle between the thighs and the horizontal plane is 30 degrees, there is no problem. It is doubtful that the distance that the thigh can take at this time is the smallest. When the angle between the thigh and the horizontal plane is 45 degrees, the distance of the whole leg is farther. When the thigh and the horizontal plane are at 90 degrees, the distance at this time is Legs can travel greater distances.

The interval value of the gear at the ankle needs to be chosen according to the distance of the thigh each time, because the greater the angle of the thigh is, the greater the distance between the leg and the sole of the foot will be. At this time, it needs to be recorded. The value is set in the activity range of the ankle gear, and record in turn what value is needed for the gear with the thigh at 0 degrees to make the whole leg and the ground be in a vertical position. After the range value of the gear at the ankle is determined, you can use this The recorded values ​​have been mass-produced, and at the same time, the coordination of the thighs, calves, and feet has been completed. Only this kind of quiet design can make Mecha 1.0 better simulate human walking behavior.

Then talk about how to make the left leg move forward after the right leg is fixed, because the interval value at the ankle has been set. At this time, the operator can give a rotation command to the gear at the left leg, and the gear at the thigh of the left leg will rotate. Drive the movement of the thigh of the left leg. At this time, the thigh of the left leg presents an angle with the vertical plane, and then drop the whole left leg. The first thing to touch the ground must be the calf of the left leg.When the calf of the left leg touches the ground, the connection between the thigh and the calf of the left leg should be in a straight line. The thigh and calf can be placed in a straight line by buckling, or the thigh and calf can be controlled by gears. on a straight line.When the thigh and calf are on the same straight line, then control the position sensor to sense the position of the entire left leg. When it is detected that the left leg is not 90 degrees to the horizontal plane, start to move the gear at the ankle. At this time, the entire left leg slows down. Slowly change position until it is perpendicular to the horizontal plane, the left and right legs are both perpendicular to the horizontal plane, and the footstep is considered complete.

(End of this chapter)