Smooth moves reduce energy consumption in robots by up to 40%

Researchers at Sweden's Chalmers University of Technology claim to have reduced the energy consumption of an industrial robot by up to 40%. The team optimised an algorithm to minimise the robot's acceleration while retaining its production time.

Optimisation of the robot's movements reduces acceleration and deceleration, as well as the time the robot is at a standstill since being at a standstill also consumes energy.

"We simply let the robot move slower instead of waiting for other robots and machines to catch up before carrying out the next sequence. The optimisation also determines the order in which the various operations are carried out to minimise energy consumption – without reducing the total execution time", said Professor Bengt Lennartson who initiated the research.

To achieve safe optimisation, several robots moving in the same area need to be coordinated. The optimisation tool will therefore initially identify where robots may collide, and the entry and exit positions for each collision zone, and for each robot path.

The optimisation programme starts by logging the movements of each robot during an operations cycle, as well as any collision zones. This information is processed by the optimiser, which generates new control instructions that can be directly executed by the robots.

"The first test results have shown a significant improvement, such as a 15 to 40% energy reduction, but the results are still preliminary. In order to estimate the actual energy savings, further testing in industry is required", said Kristofer Bengtsson, who is responsible for the implementation of the optimisation strategy.

In robot-intensive manufacturing industries, such as bodywork factories in the automotive industry, robots consume about half of the total energy used for production.

"The goal is to make this kind of optimisation standard, and included in robots from the start," added Bengtsson. "But as we all know, it takes time to bring a development product into a robust production process, with several years of engineering work."