Force controlled assembly of emergency stop button

2012 IEEE International Conference on Robotics and Automation

Linderoth

Robertsson

et al. 2012

Self Cite

The traditional way of controlling an industrial robot is to program it to follow desired trajectories. This approach is sufficient as long as the accuracy of the robot and the calibration of the workcell is good enough. In robotic assembly these conditions are usually not fulfilled, because of uncertainties, e.g., variability in involved parts and objects not gripped accurately. Using force control is one way to handle these difficulties. This paper presents a method of doing force control without a force sensor. The method is based on detuning of the low-level joint control loops, and the force is estimated from the control error. It is experimentally verified in a small part assembly task with a kinematically redundant robotic manipulator.

Section: Introductionmentioning

confidence: 99%

Force controlled robotic assembly without a force sensor

2012 IEEE International Conference on Robotics and Automation

Linderoth

Robertsson

et al. 2012

Self Cite

“…One way to incorporate sensors and specify general tasks is to use the iTaSC framework (De Schutter et al, 2007) (instantaneous Task Specification using Constraints). In (Stolt et al, 2011), it was described how this framework was used in an assembly of an emergency stop button.…”

Section: Introductionmentioning

confidence: 99%

“…A contact model is identified, and it is used to tune the force controller. The approach is finally integrated in a subassembly of an emergency stop button, previously described in (Stolt et al, 2011). A switch has to be snapped into place in a bottom box.…”

Section: Introductionmentioning

confidence: 99%

Adaptation of Force Control Parameters in Robotic Assembly

IFAC Proceedings Volumes

Linderoth

Robertsson

et al. 2012

Self Cite

Industrial robots are usually programmed to follow desired trajectories, and are very good at position-controlled tasks. New applications, however, often require physical contact between the robot and its environment, and then the position control accuracy is generally not sufficient. Force control is a suitable alternative. The environment is often stiff, and then it is crucial to design appropriate force controllers, which is non-trivial for a robot programmer. This paper presents an adaptive algorithm for choosing force control parameters, based on identification of a contact model. The algorithm is experimentally verified in an assembly task with an industrial robot.

“…Besides, all the attempts are done at the level of robot motions, focusing on determining locations. Experiences show [26] that even relatively simple sensor-based tasks, extending beyond the "drag and drop" visual programming using those tools, require a lot of time and expertise for proper implementation in mixed architecture like ours.…”

Section: Related Workmentioning

confidence: 99%

From High-Level Task Descriptions to Executable Robot Code

Stenmark

Malec

Advances in Intelligent Systems and Computing

2015

Self Cite

Abstract. For robots to be productive co-workers in the manufacturing industry, it is necessary that their human colleagues can interact with them and instruct them in a simple manner. The goal of our research is to lower the threshold for humans to instruct manipulation tasks, especially sensor-controlled assembly. In our previous work we have presented tools for high-level task instruction, while in this paper we present how these symbolic descriptions of object manipulation are translated into executable code for our hybrid industrial robot controllers.