Servosila: Motion Control & Artificial Intelligence

ADC Delay Tuning Sweep

Servosila SC-120 servo drives come with an ADC Delay Tuning function designed to enhance ADC performance.

The raw chart of un-filtered ADC data illustrates that the noise in measurements of motor phase currents is significantly dependent on ADC timing.

If ADC sampling is initiated prematurely relative to the servo drive's switching pulse, MOSFET ringing and amplifier settling become pronounced, as observed at the beginning of the chart.

Conversely, if ADC sampling is initiated too late, the sampling process extends to the end of the low-side pulse, resulting in outright data corruption, as observed at the end of the chart.

The optimal "quiet zone" is situated between these extremes. The ADC Delay Tuning function identifies this most optimal sampling point.

Starter-Generator: The "Back-Flick" Motion

All stock Servosila SC-series Servo Drives can function as starter-generator control units for piston engines and turbines. For this application, the servo drives offer a comprehensive set of configurable features, including the "Back-Flick" startup motion depicted in the video. This initial brief motion in the reverse direction assists the piston engine in acquiring the momentum necessary to overcome its Top Dead Center (TDC) points.

Additional capabilities include intelligent mid-flight restarts, automatic fault management, and both passive and active rectification during generator mode operation. The starter-generator is controlled via CAN, USB, or RC PWM interfaces and is capable of using encoders or Hall sensors.

#Kudos to V.Rutkovski

Sine Speed Reference Test under Sensorless Field-Oriented Control (FOC)

A 10-pole 1550KV electric ducted fan (EDF) was evaluated using a Servosila SC-120R Servo Drive. During the assessment, an electrical frequency of 1800Hz was achieved, corresponding to 21600 RPM. It turned out, the speed limit was reached due to the desktop power supply unit hitting its output power ceiling. Detailed lab testing to follow.

Such sine reference tests help validate the stability of sensorless motor control across the entire operational range, from zero to maximum speeds, as well as experimentally measure the control bandwidth to facilitate integration with upper-level control systems.

Provisioning a sine reference signal or a step reference signal to the input of a servo system is a classical method for experimental determination of the bandwidth or the performance characteristics of a control system. Frequency sweeps also help identify resonance frequencies.

All Servosila SC-series servo drives feature built-in firmware functions capable of generating various reference signals and plotting the responses of the servo system via an intuitive graphical interface.

A ferrite ring filter installed on the motor's phase wires attenuates high-frequency EMI emissions that interfere with radio communication systems.

An electromagnetic brake of the servo actuator is directly controlled by the SC-120R servo drive using a built-in transistor with PWM voltage modulation.

The servo actuator is equipped with a dual encoder with an RS485 interface.

#robot #joint #servo

A three-axis robotic #gimbal system utilizes Servosila SC-60R servo drives for actuation control.

The torque servo motors, equipped with high-resolution inductive encoders, operate in a direct-drive configuration (without gearboxes) to achieve the required positioning accuracy and repeatability.

The #brushless motors feature 84 poles to maximize the inverters' angular resolution.

#Kudos to Motochrome.

Servo Drive support for Dual Encoders

Servosila SC-series servo drives provide support for dual encoders via a selection of digital interfaces such as BISS-C, SSI, SPI and RS485.

Dual encoders generate readings for both motor-side and load-side (gearbox output) shaft positions via a single digital interface. Such #encoders enable compact designs for #servo actuators with hollow shafts.

Servosila SC-60 servo drives provide BISS-C, SSI and SPI digitial interfaces for connecting such dual encoders, while the newer SC-120 servo drive also introduces an additional digital RS485 interface.

Safe Torque Off (STO) / Interlock

Servosila SC-120R servo drives come with a "Safe Torque Off / Interlock" port for safety-critical applications.

The STO function disconnects the motor from power at the "bare metal" level. This function makes sure that dangerous machines do not move during maintenance or when not in use, even if firmware, network, an upper layer control system or operators "go crazy".

Whenever the STO pin is low, the STO circuitry physically disconnects the inverter's power switches from the motor. The motor starts coasting. The servo drive itself stays operational.

The same port can be used to "interlock" a master motion control board with its slave servo drives. If the master control board looses power or malfunctions, the voltage on STO pins goes low, the #servo drives are forced to stop.

The STO/Interlock function can be disabled by removing a jumper, when not employed in an application.

A robotic Tether Management System is installed on a long-endurance unmanned surface vehicle (USV).

The tether management system employs two Servosila SC-25C servo drives and a clever software program that synchronizes motion of the two axes

Kudos to #HybridRobotics

Full technical documentation package for Servosila SC-120R Servo Drive is published through Servosila web site:

Datasheet
Firmware Reference
CAD files
Programming Guide
Sample C++ Projects