## 4 Discussion
For the value \(w=25\%\), the speed amplitude \(\Delta v\) was reduced by more than half to 0.83 km/h. For the remaining values of the assistance amplification coefficient (\(w=25\)-\(75\%\)), the speed amplitude remained constant within the range of 0.73-0.83 km/h. In addition, the performed tests proved that as the assistance amplification coefficient increased, the number of propulsive cycles required to climb the hill decreased. For \(w=0\%\), 12 propulsive cycles were required and for \(w=100\%\) - 7, although, according to the test subjects, excessively high value of the amplification coefficient resulted in a more difficult control of the wheelchair when maneuvering it using hand rims. Based on the test subject questionnaires, as well as an analysis of the change in speed amplitude as a function of the assistance amplification coefficient, an optimal value of the coefficient was selected at 50%, which meant that the voltage controlling the motor had a value of 1.2275 V. For such settings, a balance was maintained between the reduction of muscle effort and manual control over the wheelchair. The operation of the amplification of the driving torque mode (t4) did not cause any delays in the control system caused by the slope detection, since this mode was not initiated by a detection of the wheelchair inclination. The t4 mode was started when the upper limb began to propel the drive wheel, which was measured with incremental encoders. As a result, this assistance mode was active already on the initial horizontal section of the track. Analyzing the kinematics of the wheelchair, it was determined that increasing the assistance amplification coefficient increases the average wheelchair speed on the ramp \(Mv\). This average for \(w=0\%\) was \(1.61\pm 0.31\) km/h, while for \(w=100\%\) it doubled and equaled \(3.25\pm 0.16\) km/h. A similar tendency was observed for the speed amplitude on the hill \(\Delta v\). The speed amplitude for the coefficient \(w=25\%\) remained constant at 1.80-1.84 km/h. However, for the remaining values of the assistance amplification coefficient, it increased, reaching \(\Delta v=4.03\pm 0.30\) km/h for \(w=100\%\). The problem of increasing amplitude resulted from the adopted algorithm that required wheelchair users to initiate wheel movement to activate support by the BLCD motors. Therefore, in this mode, assistance is turned off at the end of each propulsive cycle and is started as soon as the next one starts. The increase of the \(w\) coefficient translated to a larger torque generated by the electric motor. In mode t4, the impact of an increase in the assistant amplification coefficient on a decrease in the number of propulsive cycles required for a hill climb was also observed. For \(w=0\%\) the number of CH cycles was \(13\pm 1\), and for \(w=100\%\) it was only 2. In this mode as well, the test subjects found that higher values of the assistance amplification coefficient resulted in difficult control over manual maneuvering of the wheelchair. In addition, as was demonstrated in the subject questionnaires, even the highest assistance amplification coefficient does not significantly reduce the effort required to propel the wheelchair during a hill climb. Based on the collected data, it was found that in order to maintain a balance between the reduction of muscle effort and manual control of the wheelchair, the value of the assistance amplification coefficient should not be greater than 50%, which means the voltage controlling the electric motor should be lower than 1.5025 V.  
In addition, for each of the analyzed assistance modes, the average acceleration of the wheelchair on the slope was measured. Analysis how this average value changed provided qualitative data on the tendency of the wheelchair movement. When the average \(\Delta a\) approached zero, it meant that the wheelchair was traveling at a constant speed, and when the average moved away from zero, becoming negative, it could be assumed that the wheelchair was slowing down along the traveled path.