The Summer School on Soft Manipulation will include a practical session, which will enhance basic skills and elaborate contents covered during the Keynotes especially regarding hand design, simulation and manipulation planning. Students have to work together in teams in order to successfully solve as task which requires the usage of soft robotic technologies and the exploitation of environmental constraints.

The hands-on session will consist of three different workshops which run simultaneously, each split into two parts A and B (see Schedule). Students can participate in one of the following three:

Workshop I: Building Soft Hands for Environmental Constraint Exploitation (led by Technical University of Berlin)

In this workshop, students will build their own soft robotic hands and optimize the design and grasping/control strategy for different scenarios.

PneuFlex actuators are made almost entirely of silicone and are actuated pneumatically. Because of this, they are highly compliant and well suited for soft robotic hands. When assembled into a soft hand, the arrangement of fingers determines the behavior of the hand during grasping. But due to the compliance of the actuators,  contact with an object and its environment greatly influences the way the grasp is executed. We can actually use these contacts to make grasping more robust, e.g. by stabilizing an object against a wall while picking it up. We call this “Environmental Constraint Exploitation” (ECE). The design of the hand will influence which ECE are achievable. But at the same time, the chosen grasping strategy will create certain requirements for the design. We believe that it is necessary to co-design both hand and grasping strategies at the same time.

During the workshop, groups of students will receive a set of different PneuFlex actuators that they will assemble into a soft hand. We will provide them with tools for (manual) rapid prototyping of various hand designs. At the same time, each group will have the opportunity to explore various grasping strategies using an intuitive pneumatic control interface for their hand. This way they can iterate and improve their design and strategy for specific ECEs.

At the end of the workshop, each team will present their solution and explain their approach. Finally, everybody will compete against each other in a final ECE-Grasping-Challenge.

Workshop II: SynGrasp (led by Italian Institute of Technology)

For this part a laptop with MATLAB Simulink installed is required.

Tuesday 18th July 13.00 18.00 (5 h)

Part 1: Fundamentals of grasp modeling (~1.5 h)

  • Object Kinematics.
  • Hand Kinematics.
  • Contact models.
  • Quasistatic model of the grasp.
  • Grasp properties.
  • Hand Control.
  • Control of the object..
  • Limitations of the rigid-body assumption.
  • Compliance at joint and contact level.
  • Underactuated and compliant grasps – Soft Synergies.

Part 2: Introducing Syngrasp (~1.5 h)

  • Introduction to the Toolbox
  • Toolbox organization
  • Hand modeling
  • Grasp modeling
  • Grasp analysis
  • Graphics and GUI
  • Grasp planner

Part 3: Some examples (~2 h)

  • example 1: modeling an anthropomorphic hand
  • example 2: modeling a modular hand
  • example 3: modeling and analysis of an underactuated compliant hand
  • example 4: grasp analysis and evaluation

Thursday 20th July 15.30-18.00 (2.5 h)

  • exercise (1.5 h): modeling one robotic hand (e.g. the Allegro hand), model the grasp and analyse grasp features.
  • Discussion (1 h): workshop review, ongoing projects and challenges.

Workshop III: Manipulation/Planning (led by University of Pisa)

During this workshop we will discuss how classical results of grasping theory and new ideas can be merged to plan grasp strategies that exploit environmental constraints.
Topics include:

  • Contact constraint modeling
  • Grasp Matrix construction
  • Form Closure and Partial Form Closure
  • Force Closure
  • Dynamic force closure with environmental constraint
  • Backbone for grasp planning

We will provide some examples that will show the main problems faced on planning for soft manipulation. Students will be able to use soft hands to test their strategies.