Smart Apparel

Smart apparel is clothing that senses, records or responds, usually through small sensors and a removable electronic module. The best products solve a clear problem for a clear wearer; the worst add gadgets nobody asked for.

• Common signals: heart rate, breathing, body temperature, movement, posture, pressure and sweat. Each needs a different sensor and a different place on the body.
• Use cases: sport and training, elder and patient care, worker safety, baby monitoring, rehabilitation and fashion effects such as light-up garments.
• Ask first: who wears it, for how long, doing what, in what weather, and who will read the data?
• Smart does not replace medical devices; a garment that claims to diagnose may need regulatory approval in many places.

Activity. Write a user need statement for one wearer: who, where, what must be sensed, how often, who is alerted and how fast.

Standard to meet. State the wearer, signal, accuracy needed, time limit and who sees the data.

A garment that is uncomfortable will not be worn, and an unworn garment gives no data. Fabric choice affects both sensor contact and comfort.

• Breathable, stretchy fabrics such as cotton-elastane blends or knitted polyester keep sensors snug without chafing.
• Dry electrodes need skin contact; loose fabric loses signal, and very tight fabric is uncomfortable. Aim for firm but not tight.
• Conductive yarns, often silver-coated, carry signals; metallic coatings can wear off in washing, and some people are sensitive to metals.
• Seams over sensors cause hot spots; place seams away from contact areas.

Activity. Test two fabrics for comfort and signal on two volunteers who consent, and record scores from 1 to 5.

Standard to meet. Build a results table with both fabrics, two users, comfort and signal scores and one design decision.

Electronics in clothing must be small, low voltage, protected against sweat and easy to remove.

• Start from a ready sensor board for heart rate, movement or temperature; sewing the conductive parts can come later.
• Use a small rechargeable cell with a protection circuit and charge only with the right charger. Never use a damaged cell next to skin.
• Battery life = capacity (mAh) / average current (mA). A 400 mAh cell with a 20 mA module lasts about 20 hours.
• Keep wires short, use strain relief and seal connectors with flexible sealant.

Activity. Draw a block diagram (sensor, processor, radio, battery, charger) and calculate battery life for two data modes.

Standard to meet. Diagram is complete and the two battery-life figures are correct.

Prototype quickly with a kit before investing in special fabrics.

• Bench test the sensor first, then test it on a person, then attach it to a garment.
• Attach the module in a pocket or with snaps so it can be removed for washing.
• Test continuity of every conductive path before closing seams.
• Record every change, photograph the layout and keep the version number on the garment.

Activity. Build or plan a prototype with removable module and test it on two users.

Standard to meet. Show that the signal remains stable during walking, arm movement and sitting for five minutes each.

Washing is the harshest test a smart garment faces.

• Test cycles: gentle cold wash, air dry. Count cycles to failure.
• Detach modules, close zips and use a wash bag.
• Inspect connections, coatings and fabric after every five washes.
• Decide a minimum life such as 25 washes and design to that.

Activity. Wash-test a sample and record the number of cycles to failure and the failure cause.

Standard to meet. Log shows cycles, faults and one improvement tested.

A sensor is only useful if you know how wrong it can be.

• Compare against a trusted reference such as a medical-grade pulse meter or a manual count.
• Test at rest, walking and running; accuracy usually falls with movement.
• Report average error and worst-case error, not only the best result.
• Make claims no stronger than the evidence.

Activity. Compare your prototype with a reference and calculate average and worst-case per cent error.

Standard to meet. Calculate both figures and match the claim wording to the evidence.

The body is the most personal data source, so privacy and safety come before features.

• Collect only what is needed, explain it in plain words and let the wearer delete it.
• Store data on the phone where possible; encrypt anything that leaves the device.
• Check electrical safety, skin safety and local rules for wearable electronics and textile labelling.
• Do not share data with third parties without clear consent.

Activity. Draft a one-screen consent text and a safety checklist for your garment.

Standard to meet. Write consent text that a non-expert can read, and build a checklist of at least eight items.

A small pilot shows whether anyone wants and can use the garment.

• Recruit about ten users with consent and a clear task.
• Measure wear time, comfort, washing results and satisfaction.
• Cost per garment = fabric + module share + labour + packaging + warranty reserve.
• Decide: improve, change use, or stop.

Activity. Write a pilot plan with users, measures, cost and decision rule.

Standard to meet. Plan names ten users, a cost per unit and a go/stop rule.

L1: learner can name uses. Focus module: What smart apparel is, and who needs it (Understand, 3 h). Smart apparel is clothing that senses, records or responds, usually through small sensors and a removable electronic module. The best products solve a clear problem for a clear wearer; the worst add gadgets nobody asked for. Key points: Common signals: heart rate, breathing, body temperature, movement, posture, pressure and sweat. Each needs a different sensor and a different place on the body. Use cases: sport and training, elder and patient care, worker safety, baby monitoring, rehabilitation and fashion effects such as light-up garments. Ask first: who wears it, for how long, doing what, in what weather, and who will read the data? Smart does not replace medical devices; a garment that claims to diagnose may need regulatory approval in many places.

Speaker notes. Teach: open with the worked example. A care home wants to know when a resident gets out of bed at night. A pressure pad in a night garment or a mat is a better answer than a heart-rate shirt. The need (alert staff within 30 seconds) drives the design, not the technology. Then set the activity: Write a user need statement for one wearer: who, where, what must be sensed, how often, who is alerted and how fast. Mark against the standard: State the wearer, signal, accuracy needed, time limit and who sees the data. Check at this level: Name a use. Model answer: Sport, care or safety.

L2: learner knows materials. Focus module: Fabrics, comfort and skin (Understand, 3 h). A garment that is uncomfortable will not be worn, and an unworn garment gives no data. Fabric choice affects both sensor contact and comfort. Key points: Breathable, stretchy fabrics such as cotton-elastane blends or knitted polyester keep sensors snug without chafing. Dry electrodes need skin contact; loose fabric loses signal, and very tight fabric is uncomfortable. Aim for firm but not tight. Conductive yarns, often silver-coated, carry signals; metallic coatings can wear off in washing, and some people are sensitive to metals. Seams over sensors cause hot spots; place seams away from contact areas.

Speaker notes. Teach: open with the worked example. Two chest-band prototypes are tested. The band with flat seams and a wider elastic gives a steadier signal and fewer red marks after a one-hour walk than the narrow band with a raised seam. Then set the activity: Test two fabrics for comfort and signal on two volunteers who consent, and record scores from 1 to 5. Mark against the standard: Build a results table with both fabrics, two users, comfort and signal scores and one design decision. Check at this level: Material concern? Model answer: Skin allergy.

L3: learner can design a block. Focus module: Sensors, power and electronics (Apply, 4 h). Electronics in clothing must be small, low voltage, protected against sweat and easy to remove. Key points: Start from a ready sensor board for heart rate, movement or temperature; sewing the conductive parts can come later. Use a small rechargeable cell with a protection circuit and charge only with the right charger. Never use a damaged cell next to skin. Battery life = capacity (mAh) / average current (mA). A 400 mAh cell with a 20 mA module lasts about 20 hours. Keep wires short, use strain relief and seal connectors with flexible sealant.

Speaker notes. Teach: open with the worked example. A 400 mAh module draws 20 mA when streaming (20 hours) and about 5 mA when storing data. Storing and sending a short burst every 10 minutes averages about 6.7 mA, which extends battery life to about 60 hours (400 / 6.7). Then set the activity: Draw a block diagram (sensor, processor, radio, battery, charger) and calculate battery life for two data modes. Mark against the standard: Diagram is complete and the two battery-life figures are correct. Check at this level: Safe voltage? Model answer: Low voltage.

L4: learner can build. Focus module: Building a prototype (Apply, 4 h). Prototype quickly with a kit before investing in special fabrics. Key points: Bench test the sensor first, then test it on a person, then attach it to a garment. Attach the module in a pocket or with snaps so it can be removed for washing. Test continuity of every conductive path before closing seams. Record every change, photograph the layout and keep the version number on the garment.

Speaker notes. Teach: open with the worked example. The first sleeve prototype loses signal when the elbow bends because the wire crosses the joint. Moving the wire along the side seam with a loose loop fixes the break. Then set the activity: Build or plan a prototype with removable module and test it on two users. Mark against the standard: Show that the signal remains stable during walking, arm movement and sitting for five minutes each. Check at this level: Why removable module? Model answer: For washing.

L5: learner can test. Focus module: Washing, wear and durability (Analyse, 4 h). Washing is the harshest test a smart garment faces. Key points: Test cycles: gentle cold wash, air dry. Count cycles to failure. Detach modules, close zips and use a wash bag. Inspect connections, coatings and fabric after every five washes. Decide a minimum life such as 25 washes and design to that.

Speaker notes. Teach: open with the worked example. Three prototypes are washed. The first fails at 8 washes (corroded thread), the second at 15 (cracked sealant), the third passes 25 after a flexible silicone seal is added. Then set the activity: Wash-test a sample and record the number of cycles to failure and the failure cause. Mark against the standard: Log shows cycles, faults and one improvement tested. Check at this level: Wash test? Model answer: Count cycles to failure.

L6: learner can lead a pilot. Focus module: Privacy, safety and rules (Evaluate, 4 h). The body is the most personal data source, so privacy and safety come before features. Key points: Collect only what is needed, explain it in plain words and let the wearer delete it. Store data on the phone where possible; encrypt anything that leaves the device. Check electrical safety, skin safety and local rules for wearable electronics and textile labelling. Do not share data with third parties without clear consent.

Speaker notes. Teach: open with the worked example. A consent screen lists: what is recorded (heart rate every minute), where it is kept (the phone only), who can see it (the wearer) and how to delete it. Then set the activity: Draft a one-screen consent text and a safety checklist for your garment. Mark against the standard: Write consent text that a non-expert can read, and build a checklist of at least eight items. Check at this level: Privacy rule? Model answer: Consent and secure storage.

L7: learner can audit. Focus module: Pilot, cost and plan (Create, 3 h). A small pilot shows whether anyone wants and can use the garment. Key points: Recruit about ten users with consent and a clear task. Measure wear time, comfort, washing results and satisfaction. Cost per garment = fabric + module share + labour + packaging + warranty reserve. Decide: improve, change use, or stop.

Speaker notes. Teach: open with the worked example. The pilot garment costs 780 INR to make and is priced at 1,600 INR. Users wear it on 8 out of 10 days; two report the collar irritates, so the module moves to the side seam. Then set the activity: Write a pilot plan with users, measures, cost and decision rule. Mark against the standard: Plan names ten users, a cost per unit and a go/stop rule. Check at this level: Pilot size? Model answer: About 10 users.