John-John Cabibihan
Chapter 02Singapore and Doha

Social robots for autism

A robot is predictable and endlessly patient, which can make it a useful partner in therapy for children with autism. A robot in a playroom also gets dropped, shaken and thrown. The studies here ask how to make a small robot safe to throw, and how it can tell from its own sensors that a meltdown is coming.

523citations for the 2013 survey on why robots help in therapy
144throws at a dummy head in the shape and mass dataset
99%accuracy predicting challenging behaviour, led by heart rate
23papers since 2012, and two US patents
Safety

What if the robot is thrown?

A 2018 study warned that a small robot thrown at a head during a meltdown could cause tissue injuries, and in extreme cases a concussion. So the lab built a low-cost rig that throws objects at a dummy head fitted with an accelerometer, and measured the head injury criterion, the 3 ms criterion and peak acceleration. Pick a toy and a speed.

launcheraccelerometer at the centre0.4 kg cylinder, 2.0 m/s
0.80 Jkinetic energy at impact, ½mv²
5.3×the energy of the gentlest throw tested, 0.3 kg at 1 m/s
Mass
Shape
Soft cover

The study's safest toy was a 0.3 kg cube or wedge.

The soft material tests wrapped a 0.4 kg cylinder in Ecoflex, Dragon Skin or clay, 1 to 5 mm thick.

Sources: the rig, HardwareX 2019; shape and mass, 27 Taguchi runs; soft materials, all in 2019. Energy is computed from the mass and speed you pick. The head's motion is drawn for illustration.

Sensing

A toy that knows it is being thrown

An accelerometer inside a toy can tell a gentle pick-up from a throw. The lab recorded children playing with a stuffed panda, a stuffed robot and a toy excavator, and trained models on six behaviours: idle, pick up, shake, hit, drop and throw. Later work moved the sensors onto the child, as a wearable that also reads heart rate.

0 g1 g2 g4 g6 gacceleration, last 2 s

In free fall the reading drops to zero, then the landing shows up as a sharp spike.

2019Toy sensor, neural network80%
trained on adults, tested on children
2021Wearable, body and motion signals97%
best of the models tried
2022Toy sensor, XGBoost in real time90%
answer in 0.004 s
2023Wearable, heart rate led99%
XGBoost

Sources: RO-MAN 2019, RO-MAN 2021, IJSR 2022, Robotics 2023, and the toy dataset. Each study used its own recordings, so the bars are not one benchmark. The acceleration traces are drawn for illustration.

2022 · Qatar University

Fast enough to answer

Five machine learning methods were compared for a robot that reacts as it happens. XGBoost was the best at 90% accuracy, with an answer in 0.004 s. The accelerometer told the model more than the gyroscope did.

2023 · Qatar University

The heart rate gives it away

On a wearable, body signals beat motion signals, and heart rate was the strongest single feature. RMSSD, a measure of how much the time between heartbeats varies, tracked the challenging behaviours. This work became a US patent.

Timing

How fast should the robot answer?

When a child shakes the toy, the robot answers with a sound. If the answer comes too late, the child may not connect it to what they did. Choose a delay and shake the toy.

toyrobot1.0 sshake
Robot waits

Quick enough to feel like an answer.

A robot answered a child's action with a sound after 0.5, 1.0 or 1.5 s. For shaking, the delay made a significant difference, and the study concluded that replies slower than 1.0 s may hurt comprehension.

Source: International Journal of Social Robotics, 2020.

Along the way

Surveys, teachers and trains

2013 · NUS

Why robots?

A survey of the roles robots play in autism therapy and what they bring to it. With 523 citations, it is the most cited paper in this chapter.

International Journal of Social Robotics

2015 · QU

Asking the teachers

Six special education teachers were interviewed about robots in their classrooms. They were skeptical, saw robots doing only repetitive tasks, and expected them to be bullied.

Workshop proceedings, 2015

2015 · QU

Thomas and friends

Many children with autism love Thomas the Tank Engine, and parents report gains in social skills and speech. The paper asks why, and what that means for robots that tell social stories.

IEEE ROBIO

2016 · QU

Sensing for screening

A review of six kinds of sensors used to screen for autism and support therapy: eye trackers, movement trackers, skin conductance, touch, voice and sleep.

Sensors

2018 · QU

Robotic trains

The train went from idea to a therapy and teaching tool. Its design later became a US patent, with an arm that loads coal and a locomotive that blows bubbles.

Advances in Intelligent Systems and Computing

Record

Papers and grants

23 papers

Grants

  • 2020Smart, Snap-on Device for Detecting Aggressive Behaviors in Children with Autism during Meltdown Events
    US$150,137 · Qatar University · Lead Principal Investigator
  • 2019Safe and Adaptive Social Robots for Children with Autism (Phase II)
    US$5,492 · Qatar University · PhD Supervisor
  • 2018Safe and Adaptive Social Robots for Children with Autism
    US$5,492 · Qatar University · PhD Supervisor
  • 2014Social Robotic Toys for Children
    US$12,357 · Qatar University · Sole Investigator
  • 2012Robotics for Autism Assessment
    US$141,376 · National University of Singapore · Lead Principal Investigator