Digital microrobotic

Microrobotics deals with the design, fabrication and control of microrobots to perform tasks in the microworld (i.e. the world of submillimetric objects). While end-effectors experienced considerable developments, few works concerned the development of microrobot architectures adapted to the microworld. Most of the actual robots are bulky and based on the miniaturization of traditional architectures and kinematics. We introduce a new approach for the design of microrobot architectures based on elementary mechanical bistable modules. This bottom-up approach called “digital microrobotics” takes advantage of MEMS technology and open-loop (sensorless) digital control to offer a flexible way to experiment various kinematics adapted to the microworld. Digital microrobotics opens new perspectives in microrobots design and micromanipulation tasks. Fundamentals of digital microrobotics Digital microrobotics allows the design of microrobots adapted to the requirements of the work in the microworld. It is partially inspired by digital electronics. Digital microrobotics uses mechanical bistable modules to design robot axes and then complete microrobots and more complex devices. Mechanical bistable module A digital microrobot is built based on bistable elementary modules. Figure 1 shows the principle of a mechanical bistable module. It has two stable states. In state “0”, the module has a length of l and in state “1”, it has a length of l+d. The module can be switched from one stable state to the other by an external signal. The length of the module in the two states must be well known and repeatable. l l d State 0 State 1 Fig. 1. Principle of a mechanical bistable module.