humanoid.observer
44 robots on sale today
AIST (National Institute of Advanced Industrial Science and Technology) · Japan

HRP-4

HRP-4 was a lightweight 39 kg humanoid developed by AIST and Kawada as an affordable research platform.

Retired discontinued Score 24/100, niche Generation 4 Follows HRP-3 Promet Mk-II Succeeded by HRP-5P
No written verdict yet

We have not sat down with this one. The score below is computed from the data we hold, and the facts on this page are sourced. It is not on sale, so there is nothing to recommend.

24/100
Niche
Capability 20/30
Value 0/25
Buyability 2/20
Ecosystem 2/15
Proof 0/10
Computed from the data · how the score works

How the score is built

Capability is what the machine physically does. Value compares it with others at a similar price, not with the whole market. Buyability asks whether you can really order one. Ecosystem is the software and community around it. Proof is what it has done in the field, which is where most humanoids score badly and should.

Read the full method

Instead of this

What people buy instead.

Compare these
Unitree G1Unitree Robotics · CN · 132 cm $13,500 to $73,900List price in stock 77 Unitree R1Unitree Robotics · CN · 121 cm $4,900 to $5,900Street price in stock 64 Z-BotK-Scale Labs · US $999List price preorder 59 Noetix N2Noetix Robotics · CN · 120 cm $5,500 to $8,400Street price in stock 52
Status
Retired
Category
research
First revealed
15 September 2010
Form
bipedal
Height
151 cm
Weight
39 kg
Payload
0.5 kg
Degrees of freedom
34
Battery
n/a
Runtime
n/a
Walking speed
n/a
Actuation
electric
Units deployed (est.)
not disclosed
Teleoperation
partial

Where it stands

Slim research humanoid announced September 2010 and sold by Kawada to universities.

What stands out

  • 39 kg full-size platform

Autonomy, observed

Walking and object handling in research settings.

Hands, sensors, brain

  • Hands: simple hands
  • AI stack: OpenHRP3

Price and volume

Priced around JPY 26 million for research customers.

In the blog

HRP-4 is covered in this article

All articles
History · 6 Sep 2026

Japan built the first humanoids, then stopped shipping them

Japan has 24 humanoids and 12 makers in our record, more than any country except China and the United States. Two of the 24 can be ordered today, and both were first shown in 2009.

Same maker

Other robots by AIST (National Institute of Advanced Industrial Science and Technology).

AIST (National Institute of Advanced Industrial Science and Technology) · Japan

HRP-2 Promet

Retired

HRP-2, designed with Kawada Industries and styled by anime designer Yutaka Izubuchi, was the workhorse humanoid of the Japanese Humanoid Robotics Project and of labs such as LAAS-CNRS.

Height154 cm
Weight58 kg
Pricen/a
AIST (National Institute of Advanced Industrial Science and Technology) · Japan

HRP-3 Promet Mk-II

Retired

HRP-3 extended the HRP line with weather resistance and tool use, targeting construction and outdoor tasks.

Height161 cm
Weight68 kg
Pricen/a
AIST (National Institute of Advanced Industrial Science and Technology) · Japan

HRP-4C Miim

Retired

HRP-4C, nicknamed Miim, was built by AIST with the average proportions of a young Japanese woman and became known for singing and catwalk demonstrations.

Height158 cm
Weight43 kg
Pricenot for sale
AIST (National Institute of Advanced Industrial Science and Technology) · Japan

HRP-5P

Research

HRP-5P is AIST's construction-oriented humanoid that demonstrated autonomous drywall installation in 2018, aimed at labour shortages in Japanese building sites.

Height182 cm
Weight101 kg
Pricenot for sale

Sources

  1. 01

Spotted a wrong price or a broken fact? Send a correction. Fixed within 24 hours when sourced.