Medical Robotics and Industrial Applications

Today’s modern Robotic Systems, such as a surgical-system or a precision robotic armature, require exacting movement with no mechanical disturbances in order to provide true and accurate haptic feedback to the human operator or control system.

Haptic systems require accurate torque feedback, without mechanical disturbances to improve the human control experience. Multi-axis robots in manufacturing and semiconductor applications require low-profile frameless kits that fit inside articulating wrists, elbows, and shoulder axes while having high torque and low heat. ThinGap’s patented low-profile slotless motor technology provides zero cogging, so smooth motion,
high efficiency, and little or no hysteretic drag, allowing them to function as both a motor, and a torque sensor.

Design Considerations and Motor Selection

Engineers are faced with many design choices when it comes to designing motorized joints and precision equipment. In nearly all modern systems, compact size, deep integration, lightweight and thermal performance are all desired attributes of a solution. Motor selection is critical to system architecture, and factors in control methods, feedback requirements, and mechanical attributes. Slotless motor kits with high torque capabilities are in many cases the ideal solution for precise actuation. The most important attributes in a frameless motor are mechanical form factor, dynamic range, and torque vs. speed characteristics. Motor Constant is the only true indicator of a motor’s output torque under thermal constraints. Cogging torque is undesired in all cases that require smoothness of operation and is usually the source of down-stream vibration. Also critical to
smooth motion is sinusoidal torque versus angle curves, and phase balancing. Low inductance motors typical
of smaller size, zero cogging, weight optimized, low voltage, require higher driver PWM frequencies to minimize electrical noise or “current ripple”.

ThinGap Motor Technology

ThinGap’s motor kits are zero cogging, have near zero Eddy-current, low hysteresis, and a harmonic distortion of less than 1%, so torque output is directly proportional to current throughout the operating range. The resulting smooth motion, low profile, and linear output of ThinGap’s motor kits make them perfect for use in applications that require precision actuation and torque sensing. This facilitates a drive function and a feedback loop with target applications including robotics, flight simulators and any areas where a human operation or system need force sensing.