拆開KUKA機器人，解析工業機器人的內部結構！
一、機器人驅動裝置
概念：要使機器人運行起來, 需給各個關節即每個運動自由度安置傳動裝置 作用：提供機器人各部位、各關節動作的原動力。
驅動系統：可以是液壓傳動、氣動傳動、電動傳動, 或者把它們結合起來應用的綜合系統; 可以是直接驅動或者是通過同步帶、鏈條、輪系、諧波齒輪等機械傳動機構進行間接驅動。
1、電動驅動裝置
電動驅動裝置的能源簡單，速度變化范圍大，效率高，速度和位置精度都很高。但它們多與減速裝置相聯，直接驅動比較困難。
電動驅動裝置又可分為直流(DC)、交流(AC)伺服電機驅動和步進電機驅動。直流伺服電機電刷易磨損，且易形成火花。無刷直流電機也得到了越來越廣泛的應用。步進電機驅動多為開環控制，控制簡單但功率不大，多用于低精度小功率機器人系統。
電動上電運行前要作如下檢查：
1）電源電壓是否合適（過壓很可能造成驅動模塊的損壞）；對于直流輸入的+/-極性一定不能接錯，驅動控制器上的電機型號或電流設定值是否合適（開始時不要太大）；
2）控制信號線接牢靠，工業現場最好要考慮屏蔽問題（如采用雙絞線）；
3）不要開始時就把需要接的線全接上，只連成最基本的系統，運行良好后，再逐步連接。
4）一定要搞清楚接地方法，還是采用浮空不接。
5）開始運行的半小時內要密切觀察電機的狀態，如運動是否正常，聲音和溫升情況，發現問題立即停機調整。
2、液壓驅動
通過高精度的缸體和活塞來完成，通過缸體和活塞桿的相對運動實現直線運動。
優點：功率大，可省去減速裝置直接與被驅動的桿件相連，結構緊湊，剛度好，響應快，伺服驅動具有較高的精度。
缺點：需要增設液壓源，易產生液體泄漏，不適合高、低溫場合，故液壓驅動目前多用于特大功率的機器人系統。
選擇適合的液壓油。防止固體雜質混入液壓系統，防止空氣和水入侵液壓系統 。機械作業要柔和平順機械作業應避免粗暴，否則必然產生沖擊負荷，使機械故障頻發，大大縮短使用壽命。要注意氣蝕和溢流噪聲。作業中要時刻注意液壓泵和溢流閥的聲音，如果液壓泵出現“氣蝕”噪聲，經排氣后不能消除，應查明原因排除故障后才能使用。保持適宜的油溫。液壓系統的工作溫度一般控制在30～80℃之間為宜。
3、氣壓驅動
氣壓驅動的結構簡單，清潔，動作靈敏，具有緩沖作用。.但與液壓驅動裝置相比，功率較小，剛度差，噪音大，速度不易控制，所以多用于精度不高的點位控制機器人。
（1）具有速度快、系統結構簡單，維修方便、價格低等特點。適于在中、小負荷的機器人中采用。但因難于實現伺服控制，多用于程序控制的機械人中，如在上、下料和沖壓機器人中應用較多。
（2）在多數情況下是用于實現兩位式的或有限點位控制的中、小機器人中的。
（3）控制裝置目前多數選用可編程控制器(PLC控制器)。在易燃、易爆場合下可采用氣動邏輯元件組成控制裝置。
二、直線傳動機構
傳動裝置是連接動力源和運動連桿的關鍵部分，根據關節形式，常用的傳動機構形式有直線傳動和旋轉傳動機構。
直線傳動方式可用于直角坐標機器人的X、Y、Z向驅動，圓柱坐標結構的徑向驅動和垂直升降驅動，以及球坐標結構的徑向伸縮驅動。
直線運動可以通過齒輪齒條、絲杠螺母等傳動元件將旋轉運動轉換成直線運動，也可以有直線驅動電機驅動，也可以直接由氣缸或液壓缸的活塞產生。
1、齒輪齒條裝置
通常齒條是固定的。齒輪的旋轉運動轉換成托板的直線運動。
優點：結構簡單。
缺點：回差較大。
2、滾珠絲杠
在絲杠和螺母的螺旋槽內嵌入滾珠，并通過螺母中的導向槽使滾珠能連續循環。
優點：摩擦力小，傳動效率高，無爬行，精度高
缺點：制造成本高，結構復雜。
自鎖問題：理論上滾珠絲杠副也可以自鎖,但是實際應用上沒有使用這個自鎖的,原因主要是：可靠性很差，或加工成本很高；因為直徑與導程比非常大，一般都是再加一套蝸輪蝸桿之類的自鎖裝置。
三、旋轉傳動機構
采用旋轉傳動機構的目的是將電機的驅動源輸出的較高轉速轉換成較低轉速，并獲得較大的力矩。機器人中應用較多的旋轉傳動機構有齒輪鏈、同步皮帶和諧波齒輪。
1、齒輪鏈
（1）轉速關系
（2）力矩關系
2、同步皮帶
同步帶是具有許多型齒的皮帶，它與同樣具有型齒的同步皮帶輪相嚙合。工作時相當于柔軟的齒輪。
優點：無滑動，柔性好，價格便宜，重復定位精度高。
缺點：具有一定的彈性變形。
3、諧波齒輪
諧波齒輪由剛性齒輪、諧波發生器和柔性齒輪三個主要零件組成，一般剛性齒輪固定，諧波發生器驅動柔性齒輪旋轉。
主要特點：
(1)、傳動比大，單級為50—300。
(2)、傳動平穩，承載能力高。
(3)、傳動效率高,可達70%—90%。
(4)、傳動精度高,比普通齒輪傳動高3—4倍。
(5)、回差小，可小于3’。
(6)、不能獲得中間輸出，柔輪剛度較低。
諧波傳動裝置在機器人技術比較先進的國家已得到了廣泛的應用。僅就日本來說，機器人驅動裝置的60％都采用了諧波傳動。
美國送到月球上的機器人，其各個關節部位都采用諧波傳動裝置，其中一只上臂就用了30個諧波傳動機構。
前蘇聯送入月球的移動式機器人“登月者”，其成對安裝的8個輪子均是用密閉諧波傳動機構單獨驅動的。德國大眾汽車公司研制的ROHREN、GEROT R30型機器人和法國雷諾公司研制的VERTICAL 80型機器人等都采用了諧波傳動機構。
四、機器人傳感系統
1、感受系統由內部傳感器模塊和外部傳感器模塊組成, 用以獲取內部和外部環境狀態中有意義的信息。
2、智能傳感器的使用提高了機器人的機動性、適應性和智能化的水準。
3、智能傳感器的使用提高了機器人的機動性、適應性和智能化的水準。
4、對于一些特殊的信息, 傳感器比人類的感受系統更有效。
五、機器人位置檢測
旋轉光學編碼器是最常用的位置反饋裝置。光電探測器把光脈沖轉化成二進制波形。軸的轉角通過計算脈沖數得到，轉動方向由兩個方波信號的相對相位決定。
感應同步器輸出兩個模擬信號——軸轉角的正弦信號和余弦信號。軸的轉角由這兩個信號的相對幅值計算得到。感應同步器一般比編碼器可靠，但它的分辨率較低。
電位計是最直接的位置檢測形式。它連接在電橋中，能夠產生與軸轉角成正比的電壓信號。但是，由于分辨率低、線性不好以及對噪聲敏感。
轉速計能夠輸出與軸的轉速成正比的模擬信號。如果沒有這樣的速度傳感器，可以通過對檢測到的位置相對于時間的差分得到速度反饋信號。
六、機器人力檢測
力傳感器通常安裝在操作臂下述三個位置：
1、安裝在關節驅動器上。可測量驅動器/減速器自身的力矩或者力的輸出。但不能很好地檢測末端執行器與環境之間的接觸力。
2、安裝在末端執行器與操作臂的終端關節之間，可稱腕力傳感器。通常，可以測量施加于末端執行器上的三個到六個力/力矩分量。
3、安裝在末端執行器的“指尖”上。通常，這些帶有力覺得手指內置了應變計，可以測量作用在指尖上的一個到四個分力。
七、機器人－環境交互系統
1、機器人-環境交互系統是實現工業機器人與外部環境中的設備相互聯系和協調的系統。
2、工業機器人與外部設備集成為一個功能單元，如加工制造單元、焊接單元、裝配單元等。也可以是多臺機器人、多臺機床或設備、多個零件存儲裝置等集成 。
3、也可以是多臺機器人、多臺機床或設備、多個零件存儲裝置等集成為一個去執行復雜任務的功能單元。
八、人機交互系統
人機交互系統是使操作人員參與機器人控制并與機器人進行聯系的裝置。該系統歸納起來分為兩大類: 指令給定裝置和信息顯示裝置。

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英文版：

Unpack the KUKA robot and analyze the internal structure of the industrial robot!
First, the robot drive device
Concept: In order to make the robot run, it is necessary to place the transmissions for each joint, that is, for each degree of freedom of movement: to provide the motive force for the movement of various parts of the robot and each joint.
Drive system: It can be hydraulic drive, pneumatic drive, electric drive, or a combination of them; it can be directly driven or indirectly driven by mechanical transmission mechanisms such as timing belts, chains, trains, harmonic gears.
1. Electric drive device
The electric drive unit has a simple energy source, a wide range of speed changes, high efficiency, and high speed and position accuracy. However, they are often associated with a reduction gear, and direct drive is more difficult.
The electric drive can be divided into direct current (DC), alternating current (AC) servo motor drive and stepper motor drive. DC servo motor brushes are prone to wear and are prone to sparks. Brushless DC motors have also become more widely used. The stepper motor drive is mostly open-loop control, the control is simple but the power is not large, and it is mostly used in low-precision low-power robot systems.
Check the following before electric power-on:
1) Is the power supply voltage suitable (overvoltage is likely to cause damage to the drive module); the +/- polarity of the DC input must not be connected incorrectly, and the motor model or current setting value on the drive controller is appropriate (do not start at the beginning) Too big);
2) The control signal line is firmly connected, and the industrial site should preferably consider the shielding problem (such as using twisted pair);
3) Do not connect the wires that need to be connected when starting. Only connect to the most basic system. After running well, connect them step by step.
4) Be sure to find out the grounding method, or use the floating.
5) Closely observe the state of the motor within half an hour of starting operation, such as whether the motion is normal, sound and temperature rise, and immediately stop the adjustment after finding the problem.
2, hydraulic drive
This is done by a high-precision cylinder and piston, which is linearly moved by the relative movement of the cylinder and the piston rod.
Advantages: The power is large, and the speed reducing device can be directly connected with the driven rod member, the structure is compact, the rigidity is good, the response is fast, and the servo drive has high precision.
Disadvantages: It is necessary to add a hydraulic source, which is prone to liquid leakage, and is not suitable for high and low temperature applications. Therefore, hydraulic drive is currently used for robot systems with extra high power.
Choose the right hydraulic fluid. Prevent solid impurities from mixing into the hydraulic system and prevent air and water from invading the hydraulic system. The mechanical operation should be gentle and smooth. The mechanical operation should avoid roughness, otherwise the impact load will be generated, causing frequent mechanical failures and greatly shortening the service life. Pay attention to cavitation and overflow noise. Always pay attention to the sound of the hydraulic pump and the relief valve during the operation. If the hydraulic pump has “cavitation” noise, it cannot be eliminated after exhausting. It should be found that the cause can be used after troubleshooting. Maintain a suitable oil temperature. The working temperature of the hydraulic system is generally controlled between 30 and 80 °C.
3, pneumatic drive
The air-driven structure is simple, clean, sensitive, and has a cushioning effect. However, compared with the hydraulic drive device, the power is small, the rigidity is poor, the noise is large, and the speed is not easy to control, so it is often used for a point-controlled robot with low precision.
(1) It has the characteristics of fast speed, simple system structure, convenient maintenance and low price. Suitable for use in medium and small load robots. However, it is difficult to implement servo control, and many of them are used in program control, such as upper and lower materials and punching robots.
(2) In most cases, it is used in medium and small robots that implement two-bit or finite point control.
(3) Most of the control devices currently use programmable controllers (PLC controllers). In flammable and explosive situations, pneumatic logic components can be used to form the control device.
Second, linear transmission mechanism
The transmission is a key part of the connection between the power source and the moving link. According to the joint form, the commonly used transmission mechanism has a linear transmission and a rotary transmission mechanism.
The linear transmission mode can be used for X, Y, Z direction driving of Cartesian robots, radial driving and vertical lifting driving of cylindrical coordinate structures, and radial stretching driving of spherical coordinate structures.
The linear motion can convert the rotary motion into a linear motion through a transmission component such as a rack and pinion, a screw nut, or the like, or can be driven by a linear drive motor or directly by a piston of a cylinder or a hydraulic cylinder.
1, rack and pinion device
Usually the rack is fixed. The rotational motion of the gear is converted into a linear motion of the pallet.
Advantages: Simple structure.
Disadvantages: The difference is large.
2, ball screw
The ball is embedded in the spiral groove of the lead screw and the nut, and the ball can be continuously circulated through the guide groove in the nut.
Advantages: low friction, high transmission efficiency, no creep, high precision
Disadvantages: high manufacturing costs and complex structure.
Self-locking problem: In theory, the ball screw pair can also be self-locking, but the self-locking is not used in practical applications, mainly because of poor reliability or high processing cost; because the diameter to lead ratio is very large, Generally, a self-locking device such as a worm gear is added.
Third, the rotating transmission mechanism
The purpose of the rotary transmission mechanism is to convert the higher rotational speed of the motor's drive source output to a lower rotational speed and obtain a larger torque. Rotary transmission mechanisms that are used more in robots include gear chains, timing belts, and harmonic gears.
1, the gear chain
(1) Speed relationship
(2) Torque relationship
2, timing belt
The timing belt is a belt having a plurality of teeth that mesh with a timing pulley that also has a tooth. It is equivalent to a soft gear when working.
Advantages: no sliding, good flexibility, low price, high repeatability.
Disadvantages: There is a certain elastic deformation.
3, harmonic gear
The harmonic gear is composed of three main parts: a rigid gear, a harmonic generator and a flexible gear. Generally, the rigid gear is fixed, and the harmonic generator drives the flexible gear to rotate.
main feature: 
(1) The transmission ratio is large, and the single stage is 50-300.
(2) The transmission is stable and the carrying capacity is high.
(3), transmission efficiency is high, up to 70% -90%.
(4) High transmission precision, 3-4 times higher than ordinary gear transmission.
(5), the difference is small, can be less than 3'.
(6), the intermediate output cannot be obtained, and the flexural rigidity is low.
Harmonic transmissions have been widely used in countries with advanced robotics. In Japan alone, 60% of robotic drives use harmonic drives.
The robots sent to the moon by the United States use harmonic transmissions for each joint, and one of the upper arms uses 30 harmonic transmission mechanisms.
The mobile robot "moon stalker" sent to the moon by the former Soviet Union, the eight wheels installed in pairs are individually driven by a closed harmonic drive mechanism. The ROHREN, GEROT R30 robot developed by Volkswagen AG and the VERTICAL 80 robot developed by Renault of France all adopt harmonic drive mechanism.
Fourth, the robot sensing system
1. The sensing system consists of an internal sensor module and an external sensor module to obtain meaningful information in the internal and external environmental conditions.
2. The use of smart sensors improves the maneuverability, adaptability and intelligence of the robot.
3. The use of smart sensors improves the maneuverability, adaptability and intelligence of the robot.
4. For some special information, the sensor is more effective than the human perception system.
Five, robot position detection
Rotating optical encoders are the most commonly used position feedback devices. Photodetectors convert light pulses into binary waveforms. The rotation angle of the shaft is obtained by calculating the number of pulses, and the direction of rotation is determined by the relative phases of the two square wave signals.
The inductive synchronizer outputs two analog signals, the sine and cosine signals of the shaft angle. The corner of the shaft is calculated from the relative amplitudes of the two signals. Inductive synchronizers are generally more reliable than encoders, but have lower resolution.
Potentiometers are the most direct form of position detection. It is connected to the bridge and produces a voltage signal proportional to the angle of the shaft. However, due to low resolution, poor linearity, and sensitivity to noise.
The tachometer can output an analog signal proportional to the speed of the shaft. If there is no such speed sensor, the speed feedback signal can be obtained by the difference of the detected position with respect to time.
Sixth, robot force detection
The force sensor is usually mounted in the following three positions on the operating arm:
1. Install on the joint drive. The torque or force output of the drive/gearbox itself can be measured. However, the contact force between the end effector and the environment cannot be well detected.
2. It is installed between the end effector and the terminal joint of the operating arm and can be called the wrist force sensor. Typically, three to six force/torque components applied to the end effector can be measured.
3. Install on the “fingertip” of the end effector. Often, these forces feel that a strain gauge is built into the finger to measure one to four component forces acting on the fingertip.
Seven, robot-environment interaction system
1. The robot-environment interaction system is a system that enables industrial robots to communicate and coordinate with devices in the external environment.
2. The industrial robot is integrated with external equipment as a functional unit, such as a manufacturing unit, a welding unit, an assembly unit, and the like. It can also be integrated with multiple robots, multiple machine tools or equipment, multiple parts storage devices, and more.
3. It can also be a multi-robot, multiple machine tools or equipment, multiple parts storage devices, etc. integrated into one functional unit to perform complex tasks.
Eight, human-computer interaction system
The human-computer interaction system is a device that allows an operator to participate in robot control and to communicate with the robot. The system is grouped into two broad categories: command given devices and information display devices.
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