Table 1.

The main differences between GCH 1.0 and GCH 2.0.

GCH 1.0.	GCH 2.0.
Distributed system	Compact system
Patients have to carry an electronic box place on their belts.	Electronic component inside the crutch tube.
External cables are necessary to connect the sensors to control box placed on the patient´s belt.	Internal cables. Patients do not have any contact with cables.
External electronic components.	Internal miniature electronic components/ surface mount device (SMD).
Weight: 1150 g.	Weight: 720 g.
Non standard battery/rechargeable/700 mA.	Standard battery/AA/rechargeable/6000 mA.
Zero is not automatic.	Offset process is automatically activated.
Only for a patient walking with one or two crutches.	Several patients can use the System simultaneously, with one or two crutches.
Discretized biofeedback. System informs if the load is wrong only with a binary signal.	The physiotherapist/patient can choose between continuous or discretized visual biofeedback. In the continuous mode, the patient receives information throughout the whole process [23].
Moteview 2.0. Generic software that shows: amount of load and a simple linear chart. This is visualized by the researcher. It is not useful for the patient.	GCH Control Software 1.0.: Specific program to control assisted gait. The load could be shown in percentages of the patient´s weight-bearing (data of clinic interest). It offers specific charts and data for researchers, physiotherapists and patients. It is adaptable to the kind of patient. (Figure 2).
No database.	Patients’ clinical database.
Data sampling frequency ≤10 Hz	Data sampling frequency ≤80 Hz
The portable system. The physiotherapist selects the ideal load without percentages. It does not allow for comparisons and research.	The portable system (watch). The physiotherapists or researchers select the ideal load or the percentage of the patient’s weight-bearing (data of clinic interest).