Goniometers

Biometrics Ltd, UK

Biometrics goniometers

Biometrics’ goniometers and torsiometers are ideal for quick, simple, and accurate measurement of joint movement in multiple planes. Extremely robust, lightweight and flexible, the sensors can be comfortably worn undetected under clothing, without hindering the actual movement of the joint.

The ‘SG’ series twin axis goniometers simultaneously measure angles in up to two planes of movement. The goniometer has two separate output connectors, one measures flexion/extension, the other radial/ulnar deviation or abduction/adduction. When used to measure a single axis joint such as the knee or elbow, or when measuring a single plane of a twin axis joint, simply connect one channel, the other remains redundant.

All SG series goniometers function the same way and come in a range of sizes to suit different joints, with direct connection to Biometrics’ Data Acquisition Systems:

Biometrics goniodetails

Specifications

 Joint  Output No. of Channels A Max (mm)
A Min (mm)
 B (mm)
 C (mm)
 D (mm)
 E (mm)
SG65 Wrist Flexion/extension, radial/ulnar deviation 2  65  30  55  18  54  20
SG75 Wrist (large) Flexion/extension, radial/ulnar deviation 2  75  35  60  18  54  20
SG110 Elbow or ankle Flexion/extension, or dorsiflexion/plantarflexion and inversion/eversion 2  110  70  60  18  54  20
SG110/A Ankle Dorsiflexion/plantarflexion, inversion/eversion 2  110  70  60  18  18  54
SG150 Knee or hip Flexion/extension and valgus/varus, or flexion/extension and abduction/adduction 2  150  100  70  18  54  20
SG150/B Back Flexion/extension, lateral flexion 2  150  50  120  18  54  20
F35 Finger (DIP, PIP, MCP) or toe Flexion/extension 1  35  30  18  8  15  8

 

Transducer Type strain gauge
Life1 600,000 cycles
Accuracy
± 2º measured over a range of ± 90º
Repeatability 1º measured over a range of 90º
Operating Temperature Range +10ºC to +40ºC
Temperature Zero Drift 0.15 degrees angle / ºC

 

1Life test results have been collected by cycling the sensors through movements that would happen during everyday use. For example, placing a sensor on an adult elbow and moving from the neutral position to maximum flexion and back to the neutral position, the unit will function for typically 600,000 cycles.