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It is also important to be able to supervise the safetyfunctionality so it really works when an emergency situationtakes place。 For example, the brakes and the robot supervisionfunctionality must be cyclic tested。 This ongoing developmentof safety technology could be a first step against the saferobotics needed for future human robot collaboration in lessstructured environment than in the robot installations of today。Still another ongoing development direction can be found inusing wireless communication in robot systems (Katzel, 2004)。The biggest interest for wireless is with respect to thecommunication between the teach pendant and the controller,but there is also an interest in wireless communication betweenthe robot controller and sensors and process equipment (Frey,Endresen, Kreitz, & Scheibe, 2005)。 Experiences from testinstallations have shown that the communication itself is not amajor problemin a workshop environment but the big issues areabout safety, for example, to find concepts for safe wirelessemergency handling and for safe selection of robots at the log inof a teach pendant。 It should also be pointed out that since alarge spectrum of devices with wireless transmission isproduced for the consumer market there are possibilities tomake use of such devices as low cost user interfaces to robotcontrollers (d’Angelo & Corke, 2001)。 In a robot controldevelopment perspective, new safety mechanisms for wirelesstransmission will be important both with respect to wirelessprogramming devices and wireless sensors and actuators。A sensor type that has got increasing industrial attention thelatest years is the six degrees of freedom (DOF) force/torquesensor (ATI et al。, 2006)。 Even though robot manufacturershave been able to deliver robots with force control (Siciliano &Villani, 2000) for a long time, there has not yet been any wideruse of this functionality。 Examples of applications where sixDOF force/torque sensors are used for the control of industrialrobots are grinding, deflashing, deburring, milling, polishing,testing and assembly。 In the material removal applications, theadvantages with force sensor based control are higher processquality, easier calibration and relaxed requirements on theaccuracy of fixtures and grippers (Pires, Ramming, Rauch, &Arau ´jo, 2002) The advantages in assembly are in additionshorter cycle times, reduced impact forces and less risk ofjamming, wedging and galling (Zhang, Zhongxue, Broga ˚rdh,Wang, & Isaksson, 2004)。 In the applications for force sensorbased control, manual work with bad working conditions isoften found and health risk is therefore also a reason for theintroduction of this technology。 In order to increase the use offorce sensor controlled robots, programming and tuningmethods need to be further developed, standard sets of processparameters need to be available and low cost force sensorsshould be developed。 Fast growing applications may be foundin the automotive industry and then for drive line componentassembly, for example, for shaft insertion, spline matching andtorque converter mounting (Fig。 2)。 Since force- and torquesensing will be necessary in future human–robot collaborationthe ongoing force/torque sensor based control developmentcould be important for the understanding of how to integratethis technology into collaborative robotic systems。Just as for force control, robot vision has been used for a longtime without finding any large volume robot applications in themanufacturing industries。 One of the reasons for this is the lackof robustness of a 2D vision system in a typical workshopenvironment and therefore vision systems to control robots aremainly used where the camera scenes are well defined and thelight conditions can be controlled, for example, for objects to bepicked and placed on conveyors (ABB-3, 2004)。 However,using the 3D vision products now available on the market it ispossible to improve the robustness of robot vision and systemsolutions can be developed to increase the flexibility in, forexample, material handling, machine tending and assembly(Braintech-ref, 2006)。 Even bin picking can now be maderobust enough for industrial use (Watanabe, Kazunori,Fig。 2。 Assembly of automobile drive line components, as the torque converterin the figure, is one example where robot force control has a big potential。 Warashina, & Kumiya, 2005) and there is also the possibility tomake use of 3D vision techniques for the calibration of tools,work objects, fixtures and other robot cell components。 Themain development with respect to 3D vision is of course relatedto feature extraction and other computer vision problems andthe robot control comes in when designing high performancevision interfaces (Lippiello, Siciliano, & Villani, 2005)。Related to 3D vision is the laser tracking sensor technologyused mainly for the control of arc welding paths when theposition of the work object cannot be guaranteed (Servorobot,2006)。 These sensor types have been in use for a long time butthere is a trend towards full 3D measurements, for example, bythe introduction of more than one scanning line in thetriangulation-based tracking sensors。