Robotic Arms with Anthropomorphic Grippers for Robotic Technological

proceedings

Proceedings Robotic Arms with Anthropomorphic Grippers for † Robotic Technological Processes

Ionel Staretu 1,2 1 Design, Mechatronics and Environment Department, Transilvania University of Brasov, 500036 Brasov, Romania; [email protected]; Tel.: +40-744309186 2 Technical Sciences Academy of Romania, 030167 Bucharest, Romania Presented at the 14th International Conference on Interdisciplinarity in Engineering—INTER-ENG 2020, † Târgu Mures, , Romania, 8–9 October 2020.

Published: 28 January 2021

Abstract: The robotic arms of the human arm type, so-called collaborative robots, have been improved, optimized, and diversified greatly in recent years. However, most of them are still equipped with mechanical grippers with plier-like jaws. Equipping these robotic arms with anthropomorphic grippers is currently hampered by variants of these grippers on the market that are far too complex and at inaccessible prices to be used on a large scale. As an alternative to the familiar anthropomorphic grippers, I presented an anthropomorphic gripper with five fingers, made under my coordination, constructive, and functional, including briefly the coupling solution with a robotic arm.

Keywords: robotic arm; human arm; direct kinematic; collaborative robot; anthropomorphic gripper

1. Introduction After the advent of industrial robots in technological processes, for a long time, industrial robots have been and are equipped for parts transfer operations, with mechanical grippers with jaws. These grippers can only be used for one type of parts or a set of similar parts. There are also multi-grippers that can be used for more types of parts. The main disadvantage of these grippers is the limited range of use and the need to change the gripper in the case of another type of part in shape or size [1]. In parallel with the mechanical grippers with jaws, anthropomorphic grippers, similar to the human hand, with three to five fingers, were continuously developed and perfected. Robotic arms similar to the human arm were also developed and perfected, which became compact, precise, and reliable [2,3]. Thus, in the robotic technological processes, the classic industrial robots got to be replaced, as an increasingly obvious trend, with robotic arms/collaborative robots (cobots) equipped with anthropomorphic grippers, fixed or mounted on mobile platforms, to the more complex shape of humanoid robots. In this way, it is possible to replace human operators with these variants of humanoid arms or robots. This paper presents a unit of robotic arm/ anthropomorphic gripper that can be widely used in the robotization of technological processes for industrial products’ manufacturing.

2. Types of Collaborative Robotic Arms In the industrial robot, the robotic arm had from the beginning as a model the human arm, with the mention that the initial variants of industrial robots had large dimensions and some disproportions compared to the human arm. Anatomically and cinematically, the human arm represented in Figure1 is characterized by several elements and seven independent movements (in xyz coordinate axis): three rotations in the shoulder (ω1; ω2; ω3), one rotation in the elbow (ω4), one rotation around the forearm (ω5), and two rotations at the wrist level (ω6; ω7).

Proceedings 2020, 63, 77; doi:10.3390/proceedings2020063077 www.mdpi.com/journal/proceedings Proceedings 2020, 63, 77 2 of 9 Proceedings 2020, 63, 77 2 of 9 xyzProceedings coordinate2020, 63 axis):, 77 three rotations in the shoulder (ω1; ω2; ω3), one rotation in the elbow (ω4), 2one of 9 xyz coordinate axis): three rotations in the shoulder (ω1; ω2; ω3), one rotation in the elbow (ω4), one rotation around the forearm (ω5), and two rotations at the wrist level (ω6; ω7). rotation around the forearm (ω5), and two rotations at the wrist level (ω6; ω7).

FigureFigure 1. 1. AnatomicallyAnatomically and and cinematically cinematically the the human human arm. arm. Figure 1. Anatomically and cinematically the human arm. AsAs we we have have already already mentioned, mentioned, the the first ﬁrst variants variants of of industrial industrial robots robots only only tried tried to to copy copy the the As we have already mentioned, the first variants of industrial robots only tried to copy the structurestructure and and kinematics kinematics of of the the human human hand, hand, a a direction direction in in which which they they were were partially partially successful. successful. structure and kinematics of the human hand, a direction in which they were partially successful. However,However, in in the the last last 10–15 10–15 years, years, robotic robotic arm arm struct structuresures have have appeared appeared that that are are much much more more similar similar However, in the last 10–15 years, robotic arm structures have appeared that are much more similar toto the the human human arm arm and and have have comparable comparable performance. performance. Some Some of of these these variants variants will will be be presented presented (for (for to the human arm and have comparable performance. Some of these variants will be presented (for eacheach variant variant the the independent independent movements movements are are highlighted: highlighted: ωω1,1 …,, ... ω,7ω, corresponding7, corresponding to the to the number number of each variant the independent movements are highlighted: ω1, …, ω7, corresponding to the number of degreesof degrees of freedom, of freedom, an original an original contribution contribution of this of paper, this paper, useful useful for the for easier the easierunderstanding understanding of the degrees of freedom, an original contribution of this paper, useful for the easier understanding of the operationof the operation of these of robots). these robots). The Barrett The BarrettArm (Figur Arme (Figure2a) has2 a)been has made been since made the since early the 2000s early and 2000s is operation of these robots). The Barrett Arm (Figure 2a) has been made since the early 2000s and is particularlyand is particularly accurate. accurate. The main The features main featuresof this robotic of this arm robotic are arma height are a of height 42 cm, of length 42 cm, of length 72 cm, of particularly accurate. The main features of this robotic arm are a height of 42 cm, length of 72 cm, width72 cm, of width 34 cm, of 34weight cm, weight 27 of 27kg, of high kg, high speed, speed, and and very very good good accuracy accuracy [4]. [4 ].Figure Figure 2b2b shows shows the width of 34 cm, weight 27 of kg, high speed, and very good accuracy [4]. Figure 2b shows the UniversalUniversal Robot Robot UR UR 10 10 robotic arm. Its Its main main featur featureses are: are: it it safely safely works works alongside alongside employees employees or or Universal Robot UR 10 robotic arm. Its main features are: it safely works alongside employees or separately;separately; it it automates automates tasks tasks up up to to 22 22 lbs lbs (10 (10 kg); kg); its its reach reach radius radius is is up up to to 51.2 51.2 in in (1300 (1300 mm); mm); it it has has separately; it automates tasks up to 22 lbs (10 kg); its reach radius is up to 51.2 in (1300 mm); it has 360-degree360-degree rotationrotation on on each each wrist wrist joint, joint, 6-axis 6-axis capability, capability, and 0.1 and mm 0.1 repeatability; mm repeatability; and it is lightweight and it is 360-degree rotation on each wrist joint, 6-axis capability, and 0.1 mm repeatability; and it is lightweightand mountable and atmountable only 24.3 at lbs only and 24.3 easily lbs programmed and easily programmed to switch tasks to switch [5]. tasks [5]. lightweight and mountable at only 24.3 lbs and easily programmed to switch tasks [5].

(a) (b) (a) (b) FigureFigure 2. 2. CollaborativeCollaborative robots: robots: (a (a) )WAM WAM Barrett Barrett robotic robotic arm; arm; ( (bb)) Universal Universal Robot Robot UR UR 10 10 robotic robotic arm. arm. Figure 2. Collaborative robots: (a) WAM Barrett robotic arm; (b) Universal Robot UR 10 robotic arm. DoosanDoosan M 1013 RoboticRobotic ArmArm (Figure (Figure3 a)3a) is is characterized characterized by: by: degrees degrees of freedom:of freedom: 6; payload: 6; payload: 10 kg;10 Doosan M 1013 Robotic Arm (Figure 3a) is characterized by: degrees of freedom: 6; payload: 10 kg;reach: reach: 1300 1300 mm; mm; tool tool speed: speed: 1 m1 m/s;/s; repeatability: repeatability: ±0.10.1 mm;mm; operatingoperating temperature:temperature: 5–45 °C;◦C; weight: weight: kg; reach: 1300 mm; tool speed: 1 m/s; repeatability:± ±0.1 mm; operating temperature: 5–45 °C; weight: 3333 kg; kg; installation installation position: position: floor, floor, ceiling, ceiling, and and wall walls;s; protection rati rating:ng: IP54, IP54, I/O; I/O; ports: configured configured 33 kg; installation position: floor, ceiling, and walls; protection rating: IP54, I/O; ports: configured withwith 6 6 I/Os; I/Os; and power supply: 24 24 V/Max. V/Max. 3 3 A, A, join jointt movement movement (range/speed): (range/speed): J1; J1; J2: ±360°/120°/s;360◦/120◦/s; J3: J3: with 6 I/Os; and power supply: 24 V/Max. 3 A, joint movement (range/speed): J1; J2:± ±360°/120°/s; J3: ±160°/180°/s;160◦/180◦/s; J4, J4, J5, J5, J6: J6: ±360°/225°/s360◦/225◦/ s[6]. [6]. Figure Figure 3b3b shows shows the the robotic robotic arm arm type Elfin, Elfin, which has thethe ±±160°/180°/s; J4, J5, J6: ±±360°/225°/s [6]. Figure 3b shows the robotic arm type Elfin, which has the followingfollowing features: features: control control mode: mode: continuous continuous path path co control;ntrol; drive drive mode: mode: electric; electric; application application loading, loading, following features: control mode: continuous path control; drive mode: electric; application loading, pickpick and and place, place, condition: condition: new; new; CE CE certification; certification; trademark: trademark: Han’s Han’s Robot Robot [7]. [7]. pick and place, condition: new; CE certification; trademark: Han’s Robot [7].

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(a) (b) Figure 3. a b Figure 3. CollaborativeCollaborativeCollaborative robots:robots: robots: (( (a)) Doosan Doosan M M 1013 1013 Robotic Robotic Arm; Arm; ( (b)) Elfin Elﬁn Robotic Robotic Arm. Arm. Another variant of robotic arm of this type is ROZUM Robotics (Figure4a) characterized by Another variant of robotic arm of this type is ROZUM Robotics (Figure 4a) characterized by being ultra-lightweight and mobile (8 kg weight), strong and dexterous (3 kg payload, 700 mm reach), being ultra-lightweight and mobile (8 kg weight), strong and dexterous (3 kg payload, 700 mm reach), precise ( 0.1 mm repeatability), and fast (30 rpm/2 m/s) [8]. The KUKA robotic arm (Figure4b), precise (±0.1± mm repeatability), and fast (30 rpm/2 m/s) [8]. The KUKA robotic arm (Figure 4b), made made after a long period of improvement and optimization of KUKA classic robots, in which we after a long period of improvement and optimization of KUKA classic robots, in which we can also can also remark upon the great diﬀerence between the traditional industrial robots and articulated remark upon the great difference between the traditional industrial robots and articulated robotic robotic arms of the last generation, is characterized by a 7-DOF robotic arm and adaptation algorithms; arms of the last generation, is characterized by a 7-DOF robotic arm and adaptation algorithms; the the robot is equipped with torque sensors, allowing us to perform torque control and by extension robot is equipped with torque sensors, allowing us to perform torque control and by extension impedance control, allowing for compliant interaction and motion-adaptation [9]. impedance control, allowing for compliant interaction and motion-adaptation [9].

(a) (b)

FigureFigure 4. 4. CollaborativeCollaborativeCollaborative robots:robots: robots: (( (aa)) ROZUM ROZUM robotic robotic arm; arm; ( (bb)) KUKA KUKA robotic robotic arm. arm.

TheThe Rebel Rebel Arm Arm 1–2 1–2 robotic robotic arm arm (Figure (Figure 55a)a) isis characterizedcharacterized byby 66 DOF,DOF, withwith integratedintegrated controlcontrol systemsystem and motor;motor; anan outerouter chassis chassis that that consists consists entirely entirely of of polymers polymers and and is therefore is therefore cost-e cost-effectiveﬀective and andlight; light; an articulated an articulated arm that arm enables that applicationsenables applications involving involving human–machine human–machine collaboration; collaboration; lightweight, lightweight,internal cables; internal joints cables; that are joints suitable that are for suitable service robotics for service applications; robotics applications; and brushless and DC brushless motors DCinstead motors of stepper instead motors of stepper [10]. Themotors Panda [10]. robotic The Panda arm (Figure robotic5b) arm is characterized (Figure 5b) byis characterized a easy-to-program by a easy-to-programrobotic arm designed robotic for smallarm designed businesses for and small ability businesses to move and in seven ability axes, to designedmove in withseven a smartaxes, designedsense of “touch”;with a smart the sense Panda of can “touch”; help conduct the Panda science can help experiments, conduct science build experiments, circuit boards, build or pretestcircuit boards,equipment or pretest (two Panda equipment arms can(two even Panda work arms together can even to build work a together third) [11 to]. build a third) [11].

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(a) (b) (a) (b) Figure 5. Collaborative robots: ( a)) Rabel Rabel robotic robotic arm; ( b) Panda robotic arm. Figure 5. Collaborative robots: (a) Rabel robotic arm; (b) Panda robotic arm. All types of robotic arms presented are part of th thee so-called class of collaborative collaborative robots designed to interactAll types in of aa friendlyfriendlyrobotic arms mannermanner presented andand veryvery are part eefficientlyﬃciently of the so-called withwith thethe class humanhuman of collaborative operator.operator. These robots robotic designed arms totypically interact have in a friendlysix or more manner degrees and of very mobility efficiently and canwith be the used human individually operator. or These in pairs, robotic as human arms typicallyarms. Two Two have examples six or more are given degrees for of illustration mobility andof the can structure be used equippedindividually with or two in pairs, robot as arms human each arms.(Figure Two6 6a,b).a,b). examples are given for illustration of the structure equipped with two robot arms each (Figure 6a,b).

(a) (b) (a) (b) Figure 6. Robotic structure with two robotic arms: (a) Yaskawa type [12]; (b) ABB type [13]. FigureFigure 6. 6. RoboticRobotic structure structure with with two two robotic robotic arms: arms: (a (a) )Yaskawa Yaskawa type type [12]; [12]; (b (b) )ABB ABB type type [13]. [13]. In most cases, these robotic arms, used individually or in pairs, have been equipped and are still In most cases, these robotic arms, used individually or in pairs, have been equipped and are still equipped,In most as cases, already these mentioned, robotic arms, on a usedlarge individualscale with lygrippers or in pairs, with have jaws, been pliers, equipped or sporadically and are withstill equipped, as already mentioned, on a large scale with grippers with jaws, pliers, or sporadically with equipped,articulated as finger already grippers mentioned, (3, 4, oron 5 a fingers). large scale This with situation grippers is explainedwith jaws, by pliers, the stillor sporadically low performance with articulated finger grippers (3, 4, or 5 fingers). This situation is explained by the still low performance articulatedand affordable finger variants grippers of (3,anthropomorphic 4, or 5 fingers). Thisfinger situation grippers. is explained by the still low performance and affordable variants of anthropomorphic finger grippers. and affordableIt is time variantsfor this situationof anthropomorphic to be overcome finger and grippers. to move broadly to the endowment of robotic It is time for this situation to be overcome and to move broadly to the endowment of robotic arms armsIt ofis thetime collaborative for this situation type with to be anthropomorphi overcome and cto grippers move broadly with five to articulatedthe endowment fingers of [2,3]. robotic armsof the of collaborative the collaborative type type with with anthropomorphic anthropomorphi grippersc grippers with with five articulated five articulated fingers fingers [2,3]. [2,3]. 3. Solving the Direct Kinematic Problem with the Method of Homogeneous Operators 3. Solving the Direct Kinematic Problem with the Method of Homogeneous Operators A problem of particular importance for robotic arms of the human arm type is the solution of directA problemkinematics. of particularThe following importance is a brief for example robotic arofms solving of the direct human kinematics arm type foris the a robot solution of this of directtype, forkinematics. which the The method following of homogeneous is a brief example operators of solving is applied direct [14,15]. kinematics This methodfor a robot application of this type, for which the method of homogeneous operators is applied [14,15]. This method application

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3. Solving the Direct Kinematic Problem with the Method of Homogeneous Operators Proceedings 2020, 63, 77 5 of 9 A problem of particular importance for robotic arms of the human arm type is the solution of directinvolves kinematics. the use Theof homogeneous following is a briefoperators example of ofrotation, solving translation, direct kinematics and rotation–translation for a robot of this type,compound for which operators, the method respectively, of homogeneous for translation–ro operatorstation. is applied In Figure [14,15 7a,]. Thiswe show method the applicationform of the involves the use of homogeneous operators of rotation, translation, and rotation–translation compound homogeneous elementary translation operator of the reference system O m x m y m zm to the operators, respectively, for translation–rotation. In Figure7a, we show the form of the homogeneous reference system O n x n y n z n , by the axis x m = x n : elementary translation operator of the reference system Omxmymzm to the reference system Onxnynzn, by the axis xm = xn:  1 0 0 0  1 0 0 0      x  dnm 1 0 0 A =xT = dnm 1 0 0   (1) Amnmn= Tmnmn=  ,, (1)   00 00 11 0 0     0 0 0 1    0 0 0 1

(a) (b)

FigureFigure 7. 7. Appropriate kinematic schemes schemes for for ho homogeneousmogeneous elementary elementary operators: operators: (a) ( atranslation;) translation; (b) (brotation) rotation by by x axis;x axis; (c) ( crotation) rotation by by y axis;y axis; (d ()d rotation) rotation by by z axis.z axis.

InIn the the same same form, form, the the matrix matrix of of elementary elementary homogeneous homogeneous rotationrotation operatorsoperators bybyx x-axis,-axis, yy-axis,-axis, andandz z-axis,-axis, according according to to Figure Figure7b–d, 7b–d, are: are:   1 0 0 0   11 00 00 0 0   1 0 0 0        00 11 00 0 0  y 00 Cnm 00 SSnm  = x =x    == y ==  nm nm  Amn ARmn= R =  AmnAmn RRmnmn   mn mn 0 0 Cnm S−nm   0 0 1 0   0 0 Cnm Snm 0 0 1 0    −    00 0 0SnmS CnmC 00 − SSnm 00 Cnm  nm nm    − nm nm  (2)  1 0 0 0  (2)  1 0 0 0   0 C S 0  A = Rz =   nm − nm , mn mn z  0 Cnm − Snm 0 , A = R = 0 Snm Cnm 0  mn mn    0 Snm Cnm 0  0 0 0 1  0 0 0 1 ϕ ϕ In these matrices, Snm = sin nm and Cnm = cos nm are sines, respectively, cosines of rotation angles. Rotation is around the respective axes, from the reference system m to the reference system n. If we use two elementary homogeneous rotation and translation operators, translation and rotation ones, respectively, we can obtain compound homogeneous operators corresponding to matrices resulted by multiplying the matrices corresponding to homogeneous elementary operators.

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In these matrices, Snm = sinϕnm and Cnm = cosϕnm are sines, respectively, cosines of rotation angles. Rotation is around the respective axes, from the reference system m to the reference system n. If we use two elementary homogeneous rotation and translation operators, translation and rotation ones, Proceedingsrespectively, 2020, we63, 77 can obtain compound homogeneous operators corresponding to matrices resulted6 of by 9 multiplying the matrices corresponding to homogeneous elementary operators. Compounds operators Compoundsease, to some operators extent, the ease, kinematic to some calculation, extent, the by kine reducingmatic the calculation, number of by operations reducing of the multiplication number of operationsof the matrices of multiplication corresponding of to the rotations matrices around corresponding axes in kinematic to rotations couplings around and translations axes in kinematic between couplingsthe two axes and of translations two successive between couplings. the two Below, axes of we two exemplify successive the directcouplings. kinematic Below, problem we exemplify solving thefor direct the kinematic kinematic structure problem with solving 6 axes for (0,1,2,3,4,5) the kinemati analyzedc structure and with represented 6 axes (0,1,2,3,4,5) in Figure 8analyzed. and represented in Figure 8.

FigureFigure 8. 8.The necessaryThe necessary notations notations for solving for the solving direct thekinematics direct kinematicswith the method with of the homogeneous method of operators.homogeneous operators.

ToTo obtain the reference systemsystem coordinatescoordinates OO55xx55y5zz55 reportedreported to the referencereference systemsystem OO00xx00y0zz00 (the(the direct direct kinematics kinematics problem), problem), we we write write matrix matrix forms forms of of the the rotation rotation or or translation translation operators operators of of successivesuccessive passage from thethe referencereference system systemm mto to the the reference reference system systemn: mn:= m0, =1, 0,1,2,3,4,5; 2, 3, 4, 5; n n= =0, 0,1,...,5. 1, ..., 5. TheThe matrix matrix of of the the reference reference system coordinates OO55x55y5zz55, ,as as compared compared to to the the reference reference system OO00x0yy00zz00, , whichwhich is is a a product product of of the the transfer transfer ma matricestrices above above matrix, matrix, under under the form:

A05 = A01′A1′1A12′A2′2A23′A3′3A34′A4′4A45, (3) A05 = A010 A101A120 A202A230 A303A340 A404A45, (3) The kinematic analysis presented may be extrapolated to any other structure of the robotic arm type humanThe kinematic arm. analysis presented may be extrapolated to any other structure of the robotic arm type human arm. 4. Five-Finger Anthropomorphic Gripper for Robotic Arms 4. Five-Finger Anthropomorphic Gripper for Robotic Arms Furthermore, I describe an anthropomorphic five-finger gripper, designed under the Furthermore, I describe an anthropomorphic ﬁve-ﬁnger gripper, designed under the coordination coordination of the author, with a high degree of resemblance to the human hand made under my of the author, with a high degree of resemblance to the human hand made under my coordination, coordination, a type of gripper that is recommended to be used to equip the robotic arms described a type of gripper that is recommended to be used to equip the robotic arms described above. Figure9 above. Figure 9 shows such a robotic arm and the gripper that will be mounted on it, real variant and the CAD model [16].

Proceedings 2020, 63, 77 7 of 9 Proceedings 2020, 63, 77 7 of 9 Proceedings 2020, 63, 77 7 of 9 shows such a robotic arm and the gripper that will be mounted on it, real variant and the CAD Proceedings 2020, 63, 77 7 of 9 model [16].

Figure 9. Recommendation for coupling a human arm robot with an anthropomorphic five-finger Figuregrip. 9. Recommendation for coupling a human arm robot with an anthropomorphic five-finger grip.Figure 9. Recommendation for coupling a human arm robot with an anthropomorphic five-finger grip. ThisFigure gripper, 9. Recommendation according to forFigure coupling 10a, ahas human five degreesarm robo oft withmobility an anthropomorphic and is driven by five-finger five stepper motorsThisThisgrip. (Figure gripper, gripper, 10b). according according The implementation to to Figure Figure 10a, 10 a, hasof has the five five grip degrees degreesper is of being of mobility mobility carried and and out, is isdriven having driven by solved by five five stepper the stepper first motorspartmotors of (Figure the (Figure problem 10b). 10b). Theby The ensu implementation implementationring the compatibility of ofthe the grip gripper betweenper is isbeing the being robot carried carried and out, the out, having gripper. having solved solved the the first first partpart of of Thisthe the problem gripper, problem byaccording by ensu ensuringring to the Figure the compatibility compatibility 10a, has five between between degrees the the of robot mobility robot and and theand the gripper. is gripper. driven by five stepper motors (Figure 10b). The implementation of the gripper is being carried out, having solved the first part of the problem by ensuring the compatibility between the robot and the gripper.

(a) (b) (a) (b) Figure 10. Anthropomorphic gripper with five fingers: (a) Constructive version; (b) The stepper Figuremotors.Figure 10. 10. AnthropomorphicAnthropomorphic(a) gripper withwith ﬁvefive ﬁngers: fingers: (a )( Constructivea) Constructive version; version;(b ()b ) The (b) stepperThe stepper motors. motors. AnAnFigure example example 10. Anthropomorphic of of use use is is the the simulation simulationgripper with of of fivea a moun mountingfingers:ting (a )and andConstructive transfer transfer operationversion; operation (b of) ofThe a a metal metalstepper shaft. shaft. AccordingAccordingAnmotors. example to to Figure Figure of use 11a,b,11 a,b,is the a bearing simulation is mounted of a moun on a ting shaft. and transfer operation of a metal shaft. According to Figure 11a,b, a bearing is mounted on a shaft. An example of use is the simulation of a mounting and transfer operation of a metal shaft. According to Figure 11a,b, a bearing is mounted on a shaft.

(a) (b) (a) (b) FigureFigure 11. 11. SimulationSimulation operations: operations: (a (a) )A A bearing bearing is is mounted mounted on on a a shaft; shaft; ( (bb)) Transfer Transfer operation. operation. Figure 11. Simulation(a )operations: (a) A bearing is mounted on a shaft; (b) Transfer(b) operation. AfterAfter mounting, mounting, the the shaft shaft is is taken taken and and stored stored in a box on a suitable support (Figure 12).12). AfterThe Figuremounting, robotic 11. workstationSimulation the shaft operations: is cantaken be and optimized(a) storedA bearing in by ais boxmounted using on a suitableon Kinect a shaft; sensor,support (b) Transfer which(Figure operation. takes 12). over the movements of a human arm and transmits them to the robotic arm, the anthropomorphic gripper beingAfter conﬁgured mounting, to grip the variousshaft is partstaken usingand stored a Motion in a Leapbox on sensor a suitable (Figure support 13). (Figure 12).

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Figure 12. The shaft is stored in a box.

The robotic workstation can be optimized by using a Kinect sensor, which takes over the movements of a human arm and transmits them to the robotic arm, the anthropomorphic gripper being configured to grip various parts using a Motion Leap sensor (Figure 13). Figure 12. The shaft is stored in a box. Figure 12. The shaft is stored in a box.

FigureFigure 13.13. ControlControl solutionsolution for for the the robotic robotic structure structure with with robotic robotic arm arm and and anthropomorphic anthropomorphic finger finger grip. grip. The presentation of this solution seeks to encourage the widespread use of robotic arms equipped withThe anthropomorphic presentation of grippers this solution with five seeks fingers to encourage of average the complexity widespread achievable use of robotic at low arms cost, whichequipped really with contributes anthropomorphic to the quasi-total grippers with robotization five fingers of technologicalof average complexity processes achievable of manufacture at low andcost, assembly. which really contributes to the quasi-total robotization of technological processes of manufacture and assembly. 5. Conclusions 5. ConclusionsBased on what is presented in this paper, the following conclusions can be drawn: HumanBased on arm what type is roboticpresented arms, in this also paper, called the collaborative following robotsconclusions or cobots can ifbe their drawn: shapes are more • complex, have greatly improved and diversified in recent times; even one of the big companies • Human arm type robotic arms, also called collaborative robots or cobots if their shapes are more brought to market industrial robots and such structures. complex, have greatly improved and diversified in recent times; even one of the big companies These robotic arms, more efficient than the robotic arms from the traditional industrial robots, Figure 13.• Controlbrought tosolution market industrialfor the robo robotstic and structure such structures. with robotic arm and anthropomorphic finger are further equipped especially with jaw grippers of the pliers type that do not highlight all their grip. constructive and operational possibilities.

The presentation of this solution seeks to encourage the widespread use of robotic arms equipped with anthropomorphic grippers with five fingers of average complexity achievable at low cost, which really contributes to the quasi-total robotization of technological processes of manufacture and assembly.

5. Conclusions Based on what is presented in this paper, the following conclusions can be drawn: • Human arm type robotic arms, also called collaborative robots or cobots if their shapes are more complex, have greatly improved and diversified in recent times; even one of the big companies brought to market industrial robots and such structures.

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The maximum efficiency of collaborative robotic arms use can be achieved by equipping them • with anthropomorphic grippers, still difficult to access because of high costs, and a sometimes unnecessary complexity; As an alternative to the familiar anthropomorphic gripper, to equip robotic arms, I briefly present • an anthropomorphic gripper with five fingers, sufficiently advanced and feasible at a lower cost, made under my supervision, including a solution for coupling a robotic arm, and exemplification of use in the case of assembly and transfer operations; this is a solution that has advantages in terms of cost and operation for current applications compared to other very expensive and unjustifiably complex anthropomorphic grippers.

References

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