Design and Motion Planning for a Reconfigurable Robotic Base

Supplementary material to our publication: "Design and Motion Planning for a Reconfigurable Robotic Base"
J. Pankert et al., “Design and Motion Planning for a Reconfigurable Robotic Base,” IEEE Robotics and Automation Letters, vol. 7, no. 4, pp. 9012-9019, Oct. 2022, doi: 10.1109/LRA.2022.3189166.
Preprint of the accepted paper: arxiv.org/abs/...
Full text at IEEE Xplore: ieeexplore.iee...
Open-Source code of the control software: github.com/leg...
Abstract:
A robotic platform for mobile manipulation needs to satisfy two contradicting requirements for many real-world applications: A compact base is required to navigate through cluttered indoor environments, while the support needs to be large enough to prevent tumbling or tip over, especially during fast manipulation operations with heavy payloads or forceful interaction with the environment.
This paper proposes a novel robot design that fulfills both requirements through a versatile footprint. It can reconfigure its footprint to a narrow configuration when navigating through tight spaces and to a wide stance when manipulating heavy objects. Furthermore, its triangular configuration allows for high-precision tasks on uneven ground by preventing support switches.
A model predictive control strategy is presented that unifies planning and control for simultaneous navigation, reconfiguration, and manipulation. It converts task-space goals into whole-body motion plans for the new robot.
The proposed design has been tested extensively with a hardware prototype. The footprint reconfiguration allows to almost completely remove manipulation-induced vibrations. The control strategy proves effective in both lab experiments and during a real-world construction task.
Bibtex:
@ARTICLE{9817632, author={Pankert, Johannes and Valsecchi, Giorgio and Baret, Davide and Zehnder, Jon and Pietrasik, Lukasz L. and Bjelonic, Marko and Hutter, Marco}, journal={IEEE Robotics and Automation Letters}, title={Design and Motion Planning for a Reconfigurable Robotic Base}, year={2022}, volume={7}, number={4}, pages={9012-9019}, doi={10.1109/LRA.2022.3189166}}

[@rjung_ch]

This is the future people, glad you are on this. If I was 40 again I'd get into this field for sure.

[@albertpan7072]

Salute from Shanghai.

[@neithanm]

You guys never fail to amaze me

[@shaider1982]

I enjoyed the challeninging Autonmous Mobile Robots by ETH course on EdX
👍

[@TheJps2007]

that is a good-sized platform to carry cargo for the last mile. I used to do last-mile (in Rocky Mountian House, Alberta, Canada) till a few months ago, and having a robot to do delivery was one of my ideas. An ideal last-mile project will be a combination of the RSL robot and Boston dynamics Atlas. From this video, it looks like RSL will be ideal for carrying packages on its platform on the sidewalk, and Atlas can pick up the package from the platform and deliver it to the front door.

[@PiefacePete46]

At first glance I thought the leg joints were motorised. Using the wheel motors to move the joints, and brakes to lock them is an excellent alternative. I assume the brakes are one-off units, made specifically for this application? If they are, would off-the-shelf closed loop steppers or servos be a cost effective option?
ETH Zürich is a constant source of videos that excercise my brain-cells! Many thanks.

[@leggedrobotics]

The brakes are off-the-shelf products that you can buy: moenninghoff.de/en/products/brakes/electromagnetic-tooth-brakes/typ-560-elektromagnet-zahnhaltebremse
We decided to use such brakes instead of servo or stepper motors since they provide much higher holding torques compared to motors of the same size. The control of the brakes is much simpler, too (open/close), compared to the closed loop control of such an overdetermined system.

[@PiefacePete46]

@@leggedrobotics : Thanks for the reply. From what I can see, the brakes would maintain their current state when power is lost... a real bonus. That's a really useful project, thanks again.

[@collentinarwo1513]

Inspired

[@t83rg]

Nice one, a very flexible design!
What is the wheel motor and steering motors you use?

[@leggedrobotics]

We use ANYdrive actuator units we have repurposed from an old ANYMAL C robot. They are suitable for a construction robot because of their IP67 rating.

[@zizhdizzabagus456]

i believe u suppose to kick a robot!