Post Stroke Spasticity Rehab Helper

The spasticity is the most common post stroke effect. We construct simple open sourse Arduino -based Post Stroke Spasticity Rehab Helper.

Similar projects worth following
Stroke is 30+ (not 60+ as earlier!) now. Stroke is leading cause of disability. The spasticity is the most common post stroke consequence.
The rehabilitation of lost motor functions must be made as soon as possible. The assisted rehabilitation is maximally effective in the first month.
We construct simple and chip rehabilitation robotics device - Post Stroke Spasticity Rehab Helper. The base of the Rehab Helper is Arduino and 10 micro servos SG90. Device moves the fingers to restore plasticity and initiate rehabilitation.
Every mechanism is 5-bar linkage that converts rotational motions of servos to 2-D motion. The top of linkage is equipped by swivel, for the finger holder is attached to the swivel. The fingers are fixed with an adhesive bandage and magnetic button slasp snaps.User can select any of 17 modes .
Program code is Arduino IDE compatible, free and can be simply modified. The mechanical components can be made with 3D printer, miller or cardboard knife.

Someone in the United States has a stroke every 40 seconds, and every 80 seconds one stroke takes place in Russia. The spasticity is the most common post stroke consequence. Post-stroke rehabilitation can make people healthy again, and the faster the rehabilitation begin the more effective it is.   The Rehab Helper can make rehabilitation faster and more effective.

  • We design five-bar mechanism to convert rotational movements of servos to 2- dimensional movement of patient's fingers. Hand- therapy system of 5 mechanisms is constructed.
  • We use  servos, Arduino Nano controller board, LED MAX7219 display shields, lever arms and base, that can be made using 3d printer, miller or simply with Knife for cardboard and drill.
  • The device is powered by 5 V  DC power source. The current can be up to 2-3 Amperes.
  • We calculate approximation functions to calculate the servo angles as a function of finger base position without complex time-consuming trigonometric calculations.
  • We wrote simple Arduino - compatible code to control 10 servos.
  • It is 17 modes of movement: horizontal, vertical and mixed (arc). The modes can be selected by pressing push button.
  • Frequency and smoothness can be changed by two potentiometers.
  • The LED Display shows the mode, the number of swipes, smoothness (number of points in interpolation) and time in milliseconds between points.
  • Patient’s fingers are fixed with adhesive bandage to magnetic clasp.
  • Magnetic force is strong enough to hold the fingers, but is weak enough to detach the fingers and do not any harm.
  • Code is Arduino IDE compatible and can be changed to get any kind of finger base movement.
  • The device can be replicated according to build instruction.  Step-by-step build instruction and program code are free for download on git hub repository and from “Files” section of our hackaday page here.
  • Some devices are in clinics now under investigating of the effectiveness.

We believe that the ReHub Helper can assist in neurological rehabilitation of the   upper extremity in all  the cases when manual therapy can help:

           •  Brain tumour

           •  Cerebral palsy (CP)        
          •  cervical spine          
          •  Chronic illnesses such as multiple sclerosis (MS)

           •  Fractures and injuries of the distal upper extremity (remodelling phase)            •  Meningitis, encephalitis

           •  Motor neuron diseases, e.g. amyotrophic lateral sclerosis (ALS)

           •  Muscle dystrophy

           •  Parkinson's disease

           •  Signs of paralysis caused by slipped disc in the

            •  Spinal cord injuries

           •  Stroke (cerebral haemorrhage, ischaemic damage)

           •  Traumatic brain injury (TBI)


Build Instruction version 1.0

Adobe Portable Document Format - 1.57 MB - 09/04/2017 at 00:12



Test program for 2 servos and 2 potentiometers to control and fix the path of the node.

ino - 988.00 bytes - 09/02/2017 at 21:38



Arduino IDE code for 10-servo device

ino - 17.96 kB - 09/02/2017 at 21:38



Schematics of 10-servo device for 5 fingers, format SPlan7.0

spl7 - 27.06 kB - 09/02/2017 at 21:37



Schematics of 10-servo device for 5 fingers

JPEG Image - 404.00 kB - 09/02/2017 at 21:36


  • 1 × Controller Arduino nano R3 CH340 992-ARD-NANO30NP
  • 2 × 8 digits LED shild max7219 0,36"LED shild
  • 2 × Push button Any push button- momentary
  • 10 × Servo mini SG90 Servo mini SG90 9g Tower Pro
  • 2 × 5 kohm potentiometer Any type of linear potentiometer

View all 9 components

View all 5 project logs

  • 1
    You can download Instrucitons "BuildInstruction1.pdf" (1.4 MBytes) from the Files here

    You can download Build Instruction BuildinstructionP0.pdf from the files section here of from

  • 2
    Mathematics and program of the ReHab Helper - supplement to the main Build Insturction

    Supplement to the main Instruction - mathematics and calculations of 5-bar linkage and some program specification. You can download from the files section here of from

  • 3
    Here we show the main stages of project. The drawings of lever arms and servo bases

    We use the simplest analogue servo. You can use any kind of servos.  The bases, lever arms are shown in a figure:

    The only difficult part of mechanics component fabrication is lever arm 12. The perforation on arm must fit servo shaft perforation. We make perforation by drilling 20 holes via 18° (our servo shaft has 20 teeth) with 1mm radius drill with centers on the R=1.87 mm circle.

View all 8 instructions

Enjoy this project?



Similar Projects

Does this project spark your interest?

Become a member to follow this project and never miss any updates