Progressive GravityInvestor info

RoboTrainer · affordable rehabilitation robotics

Training beyond the point of no return.

A cable-drive weight-unloading robot that lets stroke survivors, neurological patients and deconditioned wheelchair users keep training — at a fraction of the cost of today’s hospital systems.

Jonas walking with crutches while RoboTrainer's ceiling rail carries part of his body weight
Jonas — independent RoboTrainer user. 700 m → 3 km in 8 months.
Unit price
€25,000
4–7× below incumbent systems
Per session
~€120
Viable for clinics, care homes and home use
European patent
EP 3 936 197
Granted June 2025 · EPO · UK · NO · ES
Peer-reviewed research
9+ years
Incl. an ongoing randomized clinical trial

The problem

€100,000–€200,000

Typical price of rehabilitation robotics today

At that price, rehabilitation robots stay locked inside elite hospitals.

Stroke survivors, neurological patients and deconditioned wheelchair users past the acute window are routinely written off as “chronic” and stop receiving meaningful therapy. Millions decline avoidably.

The RoboTrainer solution

One system. Three configurations.

RoboTrainer supports the user against gravity during walking and therapeutic exercise. It can be operated by therapists, helpers or family members — in clinics, care homes, and eventually at home.

Overground walking

Ceiling rail

Weight relief that follows the user along a ceiling track.

Treadmill training

Fixed overhead

Stationary mount above a treadmill for high training volume.

Strength therapy

Wall / floor mount

Pulley-redirected resistance for sit-to-stand, squats and strength work.

Designed for users with 10–20% residual muscle strength.

  • Stroke
  • Multiple sclerosis
  • Parkinson’s
  • Post-surgical
  • Deconditioned

Real outcomes

The recovery the system misses.

A documented Danish case — and an independent user’s eight-month echo.

Tina seated in her wheelchair at a rehabilitation centre
Before — wheelchair after two years of conventional rehabilitation.
Tina standing in a body-weight unloading harness during training
During — body-weight unloaded training, SDU.
Tina walking up a staircase holding the handrail
After — climbing stairs independently.

Case · Tina

Wheelchair → independence in 4 months

Tina — an office worker and mother — suffered a cerebral haemorrhage with one-sided paralysis. Over two years she trained intensively across Denmark’s leading rehabilitation centres without leaving her wheelchair. The public system then discharged her: “no potential for further rehabilitation.” The family installed a stair lift and arranged help for every daily task.

She joined a body-weight unloading trial at the University of Southern Denmark — 90 minutes, three times weekly, for four months, initially supported with 25–60% of her weight. By the end of the trial she stood independently, bore her own weight, and climbed stairs. She transitioned to conventional training without unloading.

Today Tina walks with a cane. She gets in and out of bed, uses the bathroom, dresses, and lives her day independently — the freedoms her rehabilitation team had written off.

Case · Jonas

700 m → 3 km in 8 months

A wheelchair user deconditioned after an extended passive period, training twice weekly — intermittently — on treadmill walking, sit-to-stand and squats. Walking distance fourfold, speed doubled.

“Treadmill walking with unloading improve my condition! Eight months ago I struggled to walk 700m, Today I walked three kilometres. The technology that made the difference costs one-fifth of the alternatives.”

— Jonas
Tina — RecoveryChronic stroke patient: from wheelchair to stair-climbing.

Scientific foundation

Built on peer-reviewed science.

More than nine years of continuous research, from foundational robotics to an ongoing randomized clinical trial.

Randomized clinical trial — ongoing

  1. 2024

    Robot-assisted vs. standard training in subacute ischemic stroke (RoboRehab).

    Jensen J.S., Sørensen A.S., Kruuse C. et al. · BMC Neurology, 24:233

Biomechanical validation

  1. 2024

    Acute effects of body-weight unloading on overground walking.

    Jensen J.S. et al. · J. Biomech., 162:111862

  2. 2025

    Sit-to-stand and stair-walking with dynamic body-weight unloading.

    Jensen J.S. et al. · J. Biomech., 191:112891

Clinical integration / HCI

  1. 2025

    Therapist-robot collaboration in gait rehabilitation.

    De La Rosa Gutierrez J.P. et al. · Int. J. HCS, 206:103620

  2. 2024

    Design goals for end-user development of robot-assisted training.

    De La Rosa Gutierrez J.P. et al. · Proc. ACM HCI, 8(EICS):258

Foundational research

  1. 2016

    Low-cost modular robotic system for neurological rehabilitative training.

    Sørensen A.S. et al. · IEEE ICIT

  2. 2018

    RoBody interaction: kinesthetic HRI.

    Sørensen A.S., Rasmussen G. · IEEE RO-MAN

Team

The people behind RoboTrainer.

Engineering from the University of Southern Denmark’s robotics institute, shaped from day one by the people who train on it.

Portrait of Anders Stengaard Sørensen

Founder · Inventor of RoboTrainer

Anders Stengaard Sørensen

Associate Professor, The Maersk Mc-Kinney Moller Institute, University of Southern Denmark

Anders trained as a shipbuilder at Lindø and started his career building welding robots at Odense Steel Shipyard, followed by robotics spin-outs within the Maersk group.

At SDU he holds a PhD and an MSc in Electronic Engineering, and has developed rehabilitation robotics since the first RoboTrainer prototype in 2011 — co-authoring the trial, biomechanics and clinical-integration studies above.

  • PhD, Electronic Engineering
  • Associate Professor, SDU
  • Robotics since the 1990s
Portrait of Jonas Grau Thomsen

Jonas Grau Thomsen

User ambassador

Independent RoboTrainer user — from 700 m to 3 km of walking in eight months. Demonstrates the system at events and site visits.

Placeholder

Commercial lead

To be announced

TODO: CEO / commercial co-founder — sales to municipalities, clinics and care homes.

Placeholder

Clinical advisor

To be announced

TODO: neurorehabilitation physician or physiotherapist lead, e.g. from the RoboRehab trial.

Placeholder

Regulatory & quality advisor

To be announced

TODO: EU MDR / CE-marking expertise.

Investment case

Why RoboTrainer

Intellectual property

EP 3 936 197

European patent granted June 2025 (EPO · UK · NO · ES).

Economics

4–7× cheaper

Unit price €25,000 and ~€120 per session — viable for community clinics, care homes, LMIC deployment and home use.

Evidence

RCT underway

Randomized clinical trial in subacute stroke, plus biomechanical and clinical-integration studies.

Impact alignment

  • SDG 3 Good Health & Well-being
  • SDG 5 Gender Equality
  • SDG 10 Reduced Inequalities

For investors & partners

In active conversation with mission-aligned investors and distribution partners.

To discuss investment, distribution or clinical partnerships, contact the founder directly.

Anders Stengaard Sørensen

Founder, Progressive Gravity

as@progressivegravity.com