Frequently Asked Questions

Trigno™ IM

The Trigno™ IM sensor is designed to provide rich neuromuscular information and detailed movement related data through combining EMG and IMU component data within the same sensor.
EMGworks®Each Trigno™ IM sensor collects 10 channels:

1 EMG, 3D acceleration (accelerometer)
3D angular velocity (gyroscope)
3D magnetic field data (magnetometer)

Trigno™ Standard

The Trigno™ IM sensor utilizes Delsys’ patented parallel-bar technology with proprietary stabilizing references and a fixed 1cm spacing. The result is a high quality EMG signal that limits muscle crosstalk and motion artifacts while providing consistency through reliable hardware.

Trigno™ Lab - DigitalYes, all Trigno™ IM sensors are fully compatible with prior Trigno™ base stations and the Trigno™ Personal Monitor. Due to the number of channels (160), digital data collection is a must when recording from the base station (analog outputs not supported).

Trigno™ IM - ChannelsThe acceleration maxes out at +/-16g, with lower selectable ranges of +/-2g, +/-4g and +/-8g. The gyroscope maxes out at +/-2000 deg/sec, with lower selectable ranges of +/-250 deg/sec, +/-500 deg/sec and +/-1000 deg/sec. All signal resolution is 16 bit.
The Trigno™ IM sampling specifications are as follows:

Sampling Rate
Sampling Period
EMG 1111.111 0.0135/15
ACC 148.148148 0.0135/2
GYRO 148.148148 0.0135/2
MAG 74.074074 0.0135
While the other Trigno™ EMG sensors sample at ~1926 samples/second, the IM sensor’s EMG channel samples at a lower rate to accommodate for the other 9 channels that are also being sampled onboard the sensor.
Trigno™ Sensor - DimensionsThe Trigno™ IM sensors measure 37mm x 26mm x 15mm and weight approximately 14 grams. These match the dimensions of our Trigno™ Standard and Trigno™ Flex sensors.

Delsys’ proprietary radio frequency protocol used for wireless transmission ensures that all sensors have a guaranteed inter-sensor latency less than 1 sampling period (~519µs). Therefore, no latencies are experienced between channels and all sensors begin and stop collection at the same time to accomplish universal synchronization.
Up to 16 Trigno IM sensors can be collected and processed in the Delsys software, EMGworks. We also fully support a digital software development kit (SDK), which can stream data directly into 3rd-party applications (MATLAB, LabView, C/C++ based programs, etc.).

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All data collected in EMGworks® can be converted to .csv or .txt to provide a file structure that is compatible across numerous signal processing platforms. The collected data can also be converted to .c3d, a file type that is most commonly used in C-Motion’s Visual3D software. This provides users with the freedom to batch process signals, create custom analysis pipelines, visualize data sets and more. With the .c3d export, there is also the ability to blend Trigno® IM sensor data and motion laboratory data (cameras, force plates, etc.) as these are of the same file format.
Given the capabilities of the Trigno™ system, the IM sensors are able to be triggered through use of the base station’s trigger port and Delsys Trigger Module. This creates synchronization pathways for any other systems that also support triggering. There are also several 3rd-party camera systems that have accounted for the IM sensors as part of their digital software integration, enabling users to bring in Trigno™ IM sensor data into these 3rd-party software programs. For questions on specific integration, please contact
The sensors are diverse in that they are not required to be placed over a muscle belly when recording. If movement around a joint or on top of a body segment are of interest to the user, the sensors can be positioned such that they collect local acceleration or rotational velocity in all three planes. When EMG is of interest, simply place the sensor over a muscle site with proper preparation techniques. With the ability to collect from up to 16 sensors at a time, one can mix and match placements to best suit their data collection needs.
It is well documented that changes in the recording environment can have an effect on magnetometer readings, as the magnetic field will tend to change in space. This, along with other offsets from the IMU data, can throw off sensor orientation when filtering. While sensor orientation is useful as it gives the sensor’s relative orientation in pitch, roll and yaw coordinates, it must be taken lightly for the reasons aforementioned. Instead of relying on orientation, raw accelerometer and gyroscope signals from the IMU are of a higher accuracy and can be examined closely to determine relative sensor accelerations in g and relative sensor rotations in degrees per second. With processing tools like Visual3D, rich IMU data is easily accessible for processing and providing movement information on not only the sensor, but the underlying segment it is affixed to.