A Wearable Companion for DVT Patients

Designing Interactions (2017 Fall, MIT Design Lab) Midterm Project
Designing Chatbots for Health Insurance

In-class Project
Designing Interactions
MIT Design Lab
8 weeks
Team of 2
TESSA is an IoT device for DVT patients. The compression sock monitors the patient’s vital signs to detect emergency and the chatbot monitors the patient’s diet and activity.
  • How can we empower Sanitas to become tangible as an active dialogue partner for the customers?
  • What would the future of insurance look like?
  • Built a compression sock prototype that calls a designated number when the pressure sensor is activated.
  • Prototyped a mobile app.
  • Prototyped a voiced-based chatbot with Google Home

Problem Analysis

Focus: Deep Vein Thrombosis

Deep vein thrombosis (DVT) is a chronic cardiovascular disease, which affects 0.2% of the Swiss population annually. It occurs when a blood clot develops in the deep veins of the body, 90% in the legs. This blocks the blood flow and increases the risk of more severe health conditions, such as pulmonary embolism and postphlebitic syndrome.

DVT therapies require patients to frequently exercise and closely monitor their diet. If DVT is not treated correctly, secondary diseases emerge.

System Map

Product Overview

TESSA: Thrombosis Emergency-Sensitive Stocking Application

DVT patients frequently wear DVT compression socks as a precautionary measure to avoid emergency situations such as pulmonary embolism. TESSA is an IoT device applied to DVT compression socks accompanied by smartphone app and Google Home.

Understanding the User

Restaurant owner in Zuoz
Health status
  • 55 years old
  • Slightly obese
  • has DVT in his right leg
  • keeping track of his health
  • spending less time with his insurance claims
  • have someone/something remind him of taking his medications


Beat’s doctor prescribed Beat DVT-stockings in order to lower the risk of his thrombosis spreading. Beat decides to use TESSA. TESSA’s chatbot reminds him to take his medications via push-notifications on his smartphone, so that he does not forget it even on busier and hasty days in his restaurant.

The hills are steep and the weather is cold in Zuoz, so people are more likely to stay at home and not exercise frequently. TESSA reminds Beat of exercising regularly and the benefits of doing so. One evening, Beat felt a strong pain in his leg. The pulse sensor on the sock detects this, and the in-app chatbot reacted immediately and asked him about his symptoms. TESSA identified an emergency, which required immediate attention. The chatbot reacted to both Beat’s verbal symptom descriptions and TESSA physical assessment . The chatbot set up an appointment with the nearest available doctor so that his wife Margareta could drive him there. With the help of TESSA an acute pulmonary embolism was found and prevented with immediate and aggressive use of anticoagulant medicines.

Use Cases

Case 1: Typical day

Case 2: Emergency

The chatbot asks Beat what he had for lunch. Beat takes a picture of what he had and sends it to the chatbot. The image recognition AI recognizes the food based on the picture, and suggests a healthier meal by sending him a recipe. When Beat comes home from his daily exercise, he asks the bot how much he ran today via Google home.
The compression sock tracks the user's vital signs and identifies symptoms of life-threatening conditions. In emergency scenarios, the compression sock use its integrated GPS system to notify the nearest secondary healthcare provider. Live health data is sent to the healthcare provider so that the situation can be assessed prior to the treatment.

What it does

Primarily, the sock focuses on emergency prevention - the wearable device detects the patient's vital signs that are relevant to emergency pulmonary embolism such as pulse, heart rate, and body temperature. When it detects signs of emergency, the bot quickly asks the users if they're okay via smartphone app. When there is no response, the app immediately sends an ambulance to the sock's GPS location.

Project Output

Creating an immersive environment
Using littleBits, we succeeded in making a basic working prototype of a sock that makes a phone call to the designated number when the user presses the button attached to the sock. For the smartphone app accompaniment, we designed and prototyped a basic chatbot app interface. We also made a voice-based chatbot prototype that can respond to users' voice commands via Google Home.

UI Design

Emergency Scenario 01

The compression sock detects any sign of emergency and notifies the patient.

Emergency Scenario 02

The chatbot calls an ambulance.

Typical Day Scenario 01:
Dietary Consultance

The chatbot can check on the patient's diet using image recognition.

Typical Day Scenario 02:
Running Challenge

TESSA gives the patient monthly running challenges. If the patient succeeds, TESSA rewards the patient with health-related gifts. These rewards can be used for a way to promote sponsored products.

Prototype - First Iteration

Feedbacks & Reflections

  • The chatbot interaction should mainly be chat-based, therefore the interface should clearly suggest that it is a chatbot. The interface looks more like an iOS application.
  • The emergency button in the home screen is unnecessary, since the device should be detecting the emergency by itself, not waiting for the user's action. By the time the user notices, it's probably too late.

Prototype - Second Iteration

We prototyped the sock prototoype with LittleBits, the voice interface with Google home, and the second iteration of the iOS app with inVision.