![](bg5.png)
Figure 10: V1 / V2 are used as channels to apply binary
encoded controls to each micro-robot.
Each micro-robot is assigned a unique 5-bit number
and as part of the on-board logic there is an 8-bit
UART which recovers the serial communication and
programs each micro-robot for the operation it needs
to perform. When a particular micro-robot receives a
5-bit number that does not match its assigned robot
number, the robot in question ignores the three
command bits. If, on the other hand, the 5-bit
numbers match, the robot in question will latch the
three command bits into MTJ flip-flops so that at the
next major cycle the robot in question will perform
the command specified. The UART is clocked every
minor cycle, which operates at a much higher
frequency than the major cycle. Since transmitting
each 8-bit code requires a start and stop bit, the
bandwidth required on the global communications
channel for a swarm of 32 robots is at least
10*32=320 times the major cycle, and the UART
operates at some multiple of this. For example, if the
major cycle is 1 KHz and the UART requires 8
minor cycles per bit received, the minor cycle needs
to be about 2.5 MHz because the channel needs to
transmit at least 320,000 bits/second.
6 CONCLUSIONS
We have proposed a novel approach of applying
MEMS SDA micro-robots to assist in
dermatological procedures on the assumption power
may be applied via a bandage-like substrate. We
discussed features needed on a MEMS micro-robot
to achieve this. It needs improvement from Donald
et al. (Donald et al., 2006) to provide uniform
control for turning MEMS SDAs using a much
lower voltage signal that used by Donald et al. By
adding an additional stylus arm the robot can now
turn both left and right as well as use both arms to
stop. A third stylus arm provides a micro-scalpel.
Fabricating a transistor connection between each
stylus and the parallel-plate body allows the micro-
robot to control the pull-in voltage. Using this
control capability, we also presented a new approach
to using the power grid to communicate to each
micro-robot using a binary-encoded signal which
operates at much lower voltages than previous multi-
robot SDA systems.
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