Surgical robot end effector
March - August 2019
A HAX start up developed a surgical system to assist doctors in performing lung biopsy. They superimpose a 3D scan to the patient’s CT scan to track the position of a tumor as the patient’s lungs move. They use this information to reposition a robotic arm holding the biopsy needle, increasing the doctor’s insertion accuracy. This process reduces the operation’s failure rate by 80%.
I helped them design the robotic arm end effector that holds the needle and controls its insertion.
End Effector
The end effector uses two geared DC motors to secure the needle, and another to rotate the needle to prevent it from bending or snapping during insertion. The insertion is actuated using a stepper motor.
Controller
The controller communicates over USB with the Linux machine operating the robot arm. It can drive up to 4 DC motors and 1 stepper motor, and supports up to three user input buttons.
Prototype from off-the-shelf modules assembled in an afternoon for the first tests.
Custom PCB with an ATMEGA32u4 and motor drivers, to be mounted on top of the end effector. It communicates with the master Linux machine over USB.