I am going to assume that the purchase of a wheelchair and the notes on sensors and counts indicate that you have done research, that you are documenting the sensors, limitations, and desired parameters that must exist in the normal (baseline state) and the abnormal (microcontroller control state.) I fully respect the other forum members and their concern toward ensuring that you are doing your own homework, but I also understand that a second language can often make a polite inquiry sound like a ransom demand!
we are at last year in BSc program in instrumentation and control system engineering and we need help for our project
We are going to upgrade motorized wheelchair to smart wheelchair by using deferent sensors with different positions also with different functions by using aurdino controller.
We will install 4 IR sensors for drop off in the front side to give alarm if sense any drop it will force the wheelchair to stop by cutting the power or reduce the speed.
Consider the the chair and rider are moving at top speed, would an “alarm” be the appropriate mechanical response and what is the nature of the alarm: LEDS, sound, harp music?
Perhaps the uC should intervene and alarm if the velocity is too great?
Also, 4 ultrasonic sensors for distance for front side and give alarm if distance 1 meter then other alarm if 0.5 meters with reducing the power and then cut the power.
Ah, again that “alarm” word. With 4 sensors in the front, how will these be directed; that is, what is the angular coverage vectors… 0, 90, 180, ?. If in an arc, does the 0.5 meters represent the radius of the coverage area? With different vectors, how would the display manage this? That is, 4 LEDs for each sensor with arrows painted on a display bezel? Since we are not dealing with a full-circle, the physical layout should make some kind of sense.
Finally, 2 IR sensor for right side, 2 IR sensors for left side, and 2 IR sensors for rear side. With out cutting the power in this case.
Interesting. 4 sensors to the front and 2 each to the left, right, rear. This is an area that is confusing to me and again I reference if these sensors are receiving angular vector echos?
Please we need your support from your side to make the circuit and programmed the aurdino controller and make report about that with photo and block diagram to be included in our report.
If “support” means critical analysis, I’m sure you will get that!
We wait your feedback and comments.
So, here is what I am getting from the description:
/\ /\ /\ /\ <--- 4 IR front sensors for drop-off
/\ /\ /\ /\ <--- 4 Sonar front-facing
< > <---2 pair of sonar side sensors
\/ \/ <--- 2 rear sonar sensors
If I read the intro correctly, that is 14 sensors?
So, the IR drop-off sensors would be mounted on an extension boom the length of which represents a distance calculated by the vehicle maximum forward motion AND the delay reaction time of all system components? Thus, if I purposefully tried to run myself off the upper steps, the system would “save” me from certain death?
To control the current to the DC motor, the wheelchair must already have some kind of motor controller of a solid-state nature. You will need the schematic of this to determine how to properly interface into the unit to implement an emergency cutoff or speed-reduction capability.
You need to really work on the human ergonomic concepts: sounds and display(s) of the instrumentation.