Introduction: Intro: RespiArt - a Simply Ventilator

RespiArt_v1 - simple ventilator to be used when there is no real respirator available.

STEP file with 3D geometry:

Intented to be used with AMBU bag. In figures for presentation the baloon was used instead.

Components: Nema 17 stepper motor,

arduino nanoBatery Management System for 4 x 18560 batteries,

4 x 18650 batteriesDRV8255 stepper motor driver,

3 x potentiometers 10k,

1 x M5x70 screw,

M3, M5 nuts and washers,

2 x M3x20 screw,

2 x ball bearing 5x11x5,

4 x ball bearing 3x10x4,

string approx 2mm diameter,

bottom plate, I've used floor panel 8mm,

polypropylen hydraulic pipe fi 50mm (top pipe),

wood screws 3x16

Step 1: STEP 1: Mechanics

1. Put 5x11x5 bearing in main support

2. Put M5 screw in bearings

3. Fix string to the middle of screw. I've clamped it between two M5 nut. Nuts should hide inside middle ear of support

4. Put the screw-side clutch on M5 screw

5. Put the motor side clutch on NEM axis and mount motor to the support with M3 screws

6. Put 4 x 3x10x4 beatings in side supports

7. Put roller and onr M3 washer in each side support, lock by M3x20 screw as an axis. Thread should fix screw in roller

8. Fix main support and side roller supports to the bottom plate by wood screw 3x16

9. Thread the both ends of string through side rollers and bottom plate. Observe direction of windings on M5 screw, to it exactly as in figures!

10. Thread the exds of string through top pipe holes and washer after it. Fix by knots on the other side.

Step 2: Step 2: Electronics

Description is very simplified. In the figures there is no BMS - batterries are connected directly to breadboard.


1. Batteries to BMS

2. BMS "+" to arduino VIN and DRV8255 VMOT, "-" to GND of both

3. Arduino D2, D3 pins to DRV8255 IR and STEP pins respectively

4. Arduino +5V pin to RESET, SLEEP M2 and M2

5. Arduino +5V and GND to side pins of all potentiometers

6. Adduino A5, A6, A7 pins to middle pins of FREQ, VOL and FLOW potentiometers respectively

7. DRV8255 A1,A2,B1,B2 pins to NEMA motor

8. Load respiart.ino into arduino

Step 3: Step 3: Control


FREQ is used to set total period of single cycle - inspiration + expiration (breath per minute)

VOL is used to set stroke of top pipe - corresponding to total volume of inspired gas (mL)

FLOW is used to set speed of inspiration phase (L/min)

Real values setting requires calibration on specific AMBU bag.