Mobile manipulator

As a mobile manipulator composed of a self-propelled base and a robot arm robot system is commonly referred to. They are often, especially in research and in non-industrial applications, called with the much more generalized concept of service robots. In industrial applications, however, most of mobile manipulators or mobile robots ( poor ) is spoken.

• 3.1 Pick-up and delivery services in the household
• 3.2 Care
• 3.3 picking

Components

Mobile robot platform

As mobile base both classical driverless transport systems as well as mobile robots can be used. The use of a mobile robot has the advantage that it can freely and autonomously navigate in space, and so the manipulator in problem cases ( target out of reach, manipulation is not possible from the current position of kinematically change in the position of the parts to be machined, etc. can directly support ) rather than transport it only to specified position. Here, the maneuverability of the platform of great importance. In contrast to FTS, a mobile robot can at any time approach dynamically assigned positions. However, classical differential kinematics encountered particularly in close proximity to workstations to their limits and the displacement of the robot is then only possible by more or less elaborate maneuvering. Therefore, the use of omnidirectional drives up continues to grow more.

Storage options

If the mobile manipulator objects to transport and efficient, it must be equipped with appropriate storage facilities. These can in a corresponding design, also be used to allow changing of the handle without a second arm is inserted. ( A beer bottle, which was drawn on the closing out of the box must be, for example, only off and spread in the body before it can be poured. ) More storage options make the work of the robot in principle more efficient, but also complicate the navigation of the vehicle.

Manipulator

This can be either an industrial robot and a specially designed robotic arm. Since now also a selection smaller and lighter robot arms is commercially available, the use of self-developed arms is greatly reduced. (See also: Flexible Manipulator )

Grab

The end-effector must be selected to fit the Good to be manipulated. Anthropomorphic Gripper with a plurality of movable fingers are becoming increasingly available and are mainly used in research.

Image processing

If the robot is to manipulate parts in the work environment, an image processing system is almost always required. If only firmly trained arm movements are to be executed, the offset between the actual and the platform position used when teaching must be determined and taken into account at least. In order to take over the tasks human workers, the robot must additionally with more or less disordered parts cope (also known as bin-picking known) or variable storage locations.

Coordinating control

The individual control of mobile robots and robot arms are already in use for decades and well developed. With the combination of both systems, however, a very large number of possible error and problem cases which makes it necessary to add an additional coordinating control. This should mainly independently find solutions if the commanded manipulation can not be performed from a different pose but would be possible. Helpful is the control of the overall system as a closed kinematic chain, but this is extremely difficult to implement due to high redundancy.

Security system

In principle, it is possible to use the safety devices that are used for stationary manipulator arms or normal autonomous vehicles and mobile manipulators. When a mobile manipulator but shares the workspace with people or at least other vehicles, entirely new and very high demands are placed on the security system, as many potentially hazardous situations.

Pros and Cons

The combination of mobile robot platforms with robotic arms, the resulting advantages and disadvantages are greater than the sum of their respective parts.

Advantages:

• The functionality and the potential applications skyrocket.
• The entire robot system is greatly dependent on support systems (loading and unloading, material handling, transfer devices, ...) and can thus, at least theoretically, cheaper.
• Through mobile manipulators, the automation of more complex physical activities is possible, which could only be performed by people so far and these often lead to the physical workload to health problems.
• The overall system can react much more flexible to inaccuracies and discrepancies, for example by the base of the arm is tracked, if an object is not directly accessible.

Cons:

• Due to the requirements of both these components often hinder each other: The arm needs a large stable base in order to work efficiently, however, the platform should be small and easy to navigate efficiently.
• The smaller the cycle times of the platform should be, the faster it must move and the less accurate target positions are reached. Be less precise, but the start position of the arm is known, the longer because of the necessary corrections whose cycle times.
• Should in order to increase the run time of a battery-driven platform, the overall weight and power consumption can be minimized. However, a robot arm works more efficient the more features ( and therefore also one additional components ), it combines.

Areas of application

The possible applications of mobile manipulators are varied and can not yet be fully foreseen. Some known applications are:

Pick-up and delivery services in the household

Preferably tasks for demonstration purposes are used Led by the widespread application fetch beer primarily in research projects in the field of service robotics, which also occur in private households and are therefore the media. The scientific challenge is in these tasks usually considerably higher than the expected economic benefits.

Care

As the proportion of elderly and dependent people, the demand for nurses will increase. It is expected that by 2050 the proportion of people needing care based tripled the number of employed persons. In various research projects is doubtful, especially in Japan, worked hard to care robots.

Picking

Currently, run development projects to deploy mobile manipulators in picking heavy or bulky components. There are mistakes that can result in high costs, be prevented. In addition, human workers from harmful in the long term tasks are free, what is more relevant, the further increases the Durchschschnittsalter in the workforce.

Milestones

Manufacturer

The major manufacturers of commercial mobile manipulators are:

• Germany Germany: Artur Bear Maschinenbau GmbH
• KUKA
• Neobotix GmbH

• United States of America Adept Technology